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RELIABILITY OF RENEWABLE : SOLAR

Jordan Lofthouse, BS, Strata Policy

Randy T Simmons, PhD, Utah State University

Ryan M. Yonk, PhD, Utah State University

The Institute of Political Economy (IPE) at Utah State University seeks to promote a better understanding of the foundations of a free society by conducting research and disseminating findings through publications, classes, seminars, conferences, and lectures. By mentoring students and engaging them in research and writing projects, IPE creates diverse opportunities for students in graduate programs, internships, policy groups, and business.

PRIMARY INVESTIGATORS:

Jordan Lofthouse, BS Strata Policy Randy T Simmons, Phd Utah State University Ryan M. Yonk, Phd Utah State University

STUDENT RESEARCH ASSOCIATES:

Camille Harmer Jadyn Naylor Zach Hopkins Ryan Taylor Devin Stein Garrett White Bracken Allen Michael Palmer

TABLE OF CONTENTS Executive Summary ...... 1 Introduction ...... 2 Defining Reliability ...... 2 How Works ...... 2 Photovoltaic Panels ...... 2 Concentrated Systems ...... 3 Economic Reliability of Solar Energy ...... 6 The High Cost of Solar ...... 6 Policies at the State Level ...... 6 Incentives at the National Level ...... 9 Verdict on Economic Reliability ...... 9 Physical Reliability of Solar Energy ...... 10 Variability of Solar Energy ...... 10 Efficiency and ...... 10 Location ...... 10 Implications for the Electric Grid ...... 11 What is the Grid? ...... 11 Intermittency ...... 11 Grid Imbalances ...... 12 Using ...... 13 ...... 14 The Need for Long-Distance Transmission ...... 15 Verdict on Physical Reliability ...... 16 Environmental Reliability of Solar Energy ...... 17 ...... 17 Emissions ...... 18 Manufacturing, Recycling, and Foreign Pollution ...... 19 Impacts ...... 20 Verdict on Environmental Reliability ...... 21 Case Study: Solar Energy in Germany ...... 22 Exaggerated Claims of German Solar Power ...... 22 Economic Reliability ...... 22 Physical Reliability ...... 23 Environmental Reliability ...... 24 German Solar Power Analysis ...... 25 Conclusion ...... 26

EXECUTIVE SUMMARY

Solar power’s growth is driven mainly by government policies rather than market forces. Because policymakers continue to favor the solar industry with mandates and subsidies, the reliability of solar power becomes a more pressing question. The Institute of Political Economy (IPE) at Utah State University examined the economic, physical, and environmental implications of solar power to determine its overall reliability. IPE determined that using tax dollars to mandate and subsidize solar power is not a worthwhile investment because the high costs of overcoming solar power's unreliability outweigh its limited environmental benefits.

First, solar power is heavily dependent on government subsidies and mandates, and the solar industry is not economically viable without them. State mandates attempt to increase solar energy production by requiring utilities to provide a certain amount of power from solar energy. Despite mandates and billions of taxpayer dollars in subsidies, solar power only supplied 0.4 percent of the ’ in 2014. Solar power would not exist even on this small scale without government assistance.

Second, solar power cannot effectively meet electricity demand because it is inefficient and variable. Solar are some of the least efficient electricity generators of all major energy sources. Intermittent requires solar plants to be backed up by traditional fossil plants; solar is not able to supply power consistently without serious assistance from fossil . Because government policies are causing the solar industry to grow artificially fast, current infrastructure cannot keep up with solar power’s growth.

Most solar is generated during times of the day when electricity is demanded least. Current solar facilities are generally located far from population centers, and costly transmission lines have to connect the facilities to distant consumers. Households that generate their own solar power and sell their surplus place mechanical stress on the electric grid as electricity flows both to and away from homes, increasing maintenance costs.

Third, hidden environmental costs make solar power less beneficial than most people think. Solar power reduces carbon emissions because it does not require a fuel source to burn for energy production. Solar power’s intermittency requires it to be backed up by plants, so the emission benefits of solar power are reduced whenever fossil fuels need to be burned to maintain a constant supply of power. Chinese manufacturing of solar parts also reduces net environmental benefits because of destructive waste disposal processes.

Utility-scale solar power plants also use large volumes of water in drought-stricken regions, and the facilities displace local endangered wildlife. While this report concedes the benefits of solar power’s carbon-free emissions, all of the aforementioned factors decrease solar power’s net environmental benefits, making it a less worthwhile investment.

Governments are distorting energy markets and misallocating taxpayer dollars by mandating and subsidizing solar power. Whether solar power will become reliable within the next few decades is an open question best addressed by markets, not subsidies or mandates.

Reliability of Renewable Energy: Solar 1

INTRODUCTION

Many Americans view solar energy as an substitute for traditional energy sources. Government officials reinforce this opinion by subsidizing and mandating solar energy production. It is primarily government policies, not market forces, that continue to drive the growth of solar power. The United States Energy Information Administration reported more than $5 billion spent on solar subsidies in 2013, yet solar power provided only 0.3 percent of U.S. electricity in 2013.1,2 If solar power is not reliable, it is illogical to mandate its use and to invest billions of tax dollars in it. DEFINING RELIABILITY

The term “reliability” is ambiguous and goes beyond an energy source’s ability to generate power consistently. To gain a more comprehensive understanding of solar power, IPE considered solar power’s reliability in terms of its economic, physical, and environmental implications.

We first explore solar power’s economic reliability, which we define as the ability of an energy source to be self- sustaining and affordable without government mandates or subsidies.

Second, we examine solar power’s physical reliability. For an energy source to be physically reliable, it must be able to consistently meet electricity demands by supplying and transmitting its power without interruption.

Finally, we examine solar power's environmental reliability. To be environmentally reliable, an alternative energy source must have fewer environmental impacts than traditional fossil fuels. HOW SOLAR ENERGY WORKS PHOTOVOLTAIC PANELS

Photovoltaic (PV) panels directly convert into electricity. The cells of a PV panel contain materials which absorb particles of and emit electrons, generating an electrical current. 3 The three main types of PV panels are monocrystalline , , and thin-film.4

Of the three panel types, panels are made of the highest-grade silicon, making them the most efficient type of panel. These panels convert 15-20 percent of incoming sunlight into electricity. Because monocrystalline panels are the most efficient type, they require the least surface area per unit of energy produced. They are the most expensive panel type.5

1 U.S. Energy Information Administration. (2015, March 12). Direct federal financial interventions and subsidies in energy in fiscal year 2013. Retrieved from http://www.eia.gov/analysis/requests/subsidy/ 2 U.S. Energy Information Administration. (2015, July). Monthly Energy Review. Retrieved from http://www.eia.doe.gov/totalenergy/data/monthly/pdf/sec1_7.pdf 3 Gil Knier. (2008, August 6) How Do ?. NASA . Retrieved from http://science.nasa.gov/science-news/science-at- nasa/2002/solarcells/ 4 SolarEnergy.net. Photovoltaic (PV) Systems. Retrieved from http://solarenergy.net/solar-installation/solar-panel-photovoltaic-pv- systems/ 5 Maehlum, M. A. (2015, May 18). Which solar panel type is best? Mono- vs. polycrystalline vs. thin film. Energy Informative. Retrieved from http://energyinformative.org/best-solar-panel-monocrystalline-polycrystalline-thin-film/

Reliability of Renewable Energy: Solar 2

Polycrystalline silicon panels contain lower-grade silicon than monocrystalline panels. The panels are less efficient than monocrystalline panels, converting only 13-16 percent of incoming sunlight into electricity. These panels require a larger surface area to generate the same amount of electricity produced by monocrystalline panels.6

Thin-film solar cells consist of one or more ultra-thin light-absorbing layers.7 The thin-film manufacturing process is simpler than the monocrystalline or polycrystalline manufacturing process but results in panels with lower electricity conversion rates that range from 7-13 percent.8 Because of these lower conversion rates, even more surface area is needed to achieve the same energy generation as either of the other panel types. Thin-film solar cells are the cheapest PV panel system.9

CONCENTRATED SOLAR POWER SYSTEMS

Concentrated solar power (CSP) systems, also known as thermal solar power systems, do not directly convert sunlight into electricity like PV panels. These systems consist of an array of or that focus the 's rays onto a thermal receiver. The concentrated energy is used to heat water, and the resulting steam is used to drive turbines which generate electricity.10

There are three main types of CSP systems. The first is a linear concentrator system, depicted in Figure 1. Long U- shaped mirrors focus sunlight onto fluid-filled tubes that run along each . Once the fluid is heated, it flows to a heat exchanger where it is used to boil water into steam. The steam runs a turbine generator, producing electricity.11

6 Ibid. 7 Harris, W. (n.d.). How thin-film solar cells work. How Stuff Works. Retrieved July 7, 2015, from http://science.howstuffworks.com/environmental/green-science/thin-film-solar-cell1.htm 8 Maehlum, M. A. (2015, May 18). Which solar panel type is best? Mono- vs. polycrystalline vs. thin film. Retrieved from http://energyinformative.org/best-solar-panel-monocrystalline-polycrystalline-thin-film/#thin-film-solar-cells 9 Solar lease - Solar Panel Costs. (2015, May 8). Retrieved July 7, 2015, from http://www.sunrun.com/solar-lease/cost-of-solar/solar-panels 10 National Renewable Energy Laboratory. (2014, July 25). Concentrating solar power basics. Retrieved from http://www.nrel.gov/learning/re_csp.html 11 National Renewable Energy Laboratory. (2013, August 20). Linear Concentrator System Basics for Concentrating Solar Power. Retrieved from http://energy.gov/eere/energybasics/articles/linear-concentrator-system-basics-concentrating-solar-power

Reliability of Renewable Energy: Solar 3

FIGURE 1. LINEAR CONCENTRATOR SYSTEM.12

The second type of CSP system is a dish/engine system, as shown in Figure 2. Dish-shaped mirrors concentrate light onto a power conversion unit. Inside this unit, a fluid-filled thermal receiver is heated to power a small electricity- generating turbine.13

FIGURE 2. DISH/ENGINE SYSTEM.14

12 Yokogawa Corporation of America. (n.d.) Example of Trough . Retrieved from at http://c15181564.r64.cf2.rackcdn.com/image_3294.jpg 13 National Renewable Energy Laboratory. (2013, August 20). Concentrating Solar Power Dish/Engine System Basics. Retrieved from http://energy.gov/eere/energybasics/articles/concentrating-solar-power-dishengine-system-basics 14 US Department of Energy. (2013, August 20). Concentrating Solar Power Dish/Engine System Basics. Retrieved from http://energy.gov/eere/energybasics/articles/concentrating-solar-power-dishengine-system-basics

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The third type of CSP system is the power tower. A field of large, flat mirrors focus sunlight onto a thermal receiver on top of a tower. The receiver heats a fluid that is used to boil water. The steam from this water turns electricity- generating turbines.15

FIGURE 3. POWER TOWER SYSTEM.16

15 National Renewable Energy Laboratory. (2014, July 25). Concentrating solar power basics. Retrieved from http://www.nrel.gov/learning/re_csp.html 16 Department of Energy. (1996). Concentrating Solar Tower Illustration. Retrieved from https://www.eeremultimedia.energy.gov/solar/graphics/concentrating_solar_power_tower_plant_illustration

Reliability of Renewable Energy: Solar 5

ECONOMIC RELIABILITY

For solar power to be economically reliable, it must be a financially viable source of energy without government incentives. Federal and state governments encourage solar energy production through mandates, subsidies, and financial incentive programs. The cost of funding these incentives is borne by American taxpayers and places a heavier burden on the lower class through raised energy prices. In many states, electric utilities struggle to keep up with ambitious renewable energy requirements set by their governments. Solar energy is not yet an economically viable source of energy because it is expensive, relies heavily on government assistance, and is a burden to American taxpayers. THE HIGH COST OF SOLAR

Solar is a more expensive electricity source than traditional alternatives like or . Cost estimates for electricity production are typically given in the form of a Levelized Cost of Electricity (LCOE), which measures a power plant’s average costs over its lifetime, including its construction, fuel, operations, maintenance, and efficiency. The levelized cost of solar power is $125.3 per megawatt-hour for a PV plant and $239.7 per megawatt-hour for solar thermal plants. In comparison, conventional coal plants cost $95.1 per megawatt-hour, natural gas combined cycle plants cost $75.2 per megawatt-hour, and advanced nuclear plants cost $95.2 per megawatt-hour.17 Solar power plants may have zero fuel costs, but their electricity still comes at a high price compared to other electricity sources when lifetime costs are taken into consideration.

Though LCOEs show that solar is an expensive form of energy, these numbers still underestimate the costs associated with solar. LCOEs are inaccurate assessments of intermittent energy sources because they do not include the costs of balancing intermittency. When intermittent power sources are added to a power system, conventional power plants have to be held on standby so they can be ramped up when an intermittent plant is not generating enough power. Because the costs of ramping traditional power plants are not included in LCOEs,18 solar and power are portrayed to be more cost-effective than they actually are. POLICIES AT THE STATE LEVEL RENEWABLE PORTFOLIO STANDARDS AND SOLAR CARVE OUTS

Even though solar power is expensive, states mandate its adoption. Renewable portfolio standards (RPS) are state- based policies that mandate certain portions of a state’s energy production come from renewable sources. Within these standards, some states mandate which renewable sources of energy they will use to accomplish their overall RPS goal. These specifications are called carve outs. New Jersey, for instance, has a carve out mandating that 4.1 percent of its electricity must come from solar power by 2028.19

Solar is a key feature of many states’ RPS mandates. Out of the 29 states with RPS mandates, 20 have set aside solar carve outs or provisions for .20 Distributed generation refers to energy that is produced near the

17 U.S. Energy Information Administration. (2015, June 3). Levelized cost and levelized avoided cost of new generation in the annual energy outlook 2015. Retrieved from http://www.eia.gov/forecasts/aeo/electricity_generation.cfm 18 Sun, wind and drain. (2014, July 26). The Economist. Retrieved from http://www.economist.com/news/finance-and-economics/21608646- wind-and-solar-power-are-even-more-expensive-commonly-thought-sun-wind-and 19 U.S. Department of Energy. (2015, May 20). Renewable Portfolio Standard. DSIRE. Retrieved from http://programs.dsireusa.org/system/program/detail/564 20 U.S. Department of Energy. (2015, March). Renewable portfolio standards (RPS) with solar or distributed generation provisions. DSIRE.

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place it is consumed. A large portion of distributed generation is produced by small scale PV panels. States’ requirements for distributed generation and solar carve outs vary. North Carolina, for example, requires only 0.2 percent solar generation by 2018, while requires 4.5 percent distributed generation by 2025.21

Despite their efforts, many states have been unable to meet their general RPS mandates. According to the Institute for Energy Research, ’s RPS mandated that by 2010 a full 20 percent of its electricity would be generated through renewables. By the end of 2009, California was only producing 13 percent of its electricity from renewable sources.22 Similarly, New Jersey called for 6.5 percent of its electricity to be generated by renewable sources by 2009, but achieved only 1.53 percent renewable generation.23

States that have RPS mandates have seen significant economic damage since RPS implementation. A recent study analyzed state economies 48 months before and after a state adopted RPS. On average, states that enacted RPS experienced a 10 percent increase in unemployment, a 14 percent decline in electricity sales, and nearly a 4 percent drop in the state’s real income.24 RPS mandates may be contributing to these economic downturns by skewing market incentives for electricity producers, encouraging expensive renewable like solar, and increasing electricity prices.

STATE-BASED SUBSIDIES AND FINANCING FOR SOLAR POWER

Because solar power is an expensive energy source, it is expensive to subsidize. Some states, such as Connecticut and New Jersey, have had to cut back incentive availability and rebates for solar installers.25 For California to achieve its mandate of 33 percent renewable energy by 2020, an estimated $115 billion would need to be spent on infrastructure alone.26

Even when states are able to fund their solar programs, the environmental benefits are minimal, making solar subsidy money better suited for use in other sectors. A study from the George Washington Institute of Public Policy analyzed the effects of solar incentive programs in ten states and estimated that existing solar incentive programs would save 6.1 million metric tons of over a 20 year period.27 This 20 year reduction is less than what two coal

Retrieved from http://ncsolarcen-prod.s3.amazonaws.com/wp-content/uploads/2015/01/RPS-carveout-map1.pdf 21 National Renewable Energy Laboratory. (n.d.) Renewable portfolio standards. Retrieved from http://www.nrel.gov/tech_deployment/state_local_governments/basics_portfolio_standards.html 22 Institute for Energy Research. (n.d.) The status of renewable electricity mandates in the states. p. 25. Retrieved from https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB4QFjAA&url=http%3A%2F%2Finstitutefor energyresearch.org%2Fwp-content%2Fuploads%2F2011%2F01%2FIER-RPS-Study- Final.pdf&ei=l32MVa3mAsTaoATN4azIAg&usg=AFQjCNGiPd81QNVqWxAl2waz0UMzsdpxww&bvm=bv.96782255,d.cGU 23 Institute for Energy Research. (n.d.) The status of renewable electricity mandates in the states. p. 50. Retrieved from https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB4QFjAA&url=http%3A%2F%2Finstitutefor energyresearch.org%2Fwp-content%2Fuploads%2F2011%2F01%2FIER-RPS-Study- Final.pdf&ei=l32MVa3mAsTaoATN4azIAg&usg=AFQjCNGiPd81QNVqWxAl2waz0UMzsdpxww&bvm=bv.96782255,d.cGU 24 Simmons, R. T., Brough, T., Sim, K., Fishbeck, J. (2015). Renewable Portfolio Standards: Kansas. The Institute of Political Economy, Utah State University. Retrieved from: http://www.strata.org/wp-content/uploads/2015/03/Final-Report.pdf 25 Sarzynski, A. (2009, November). The impact of solar incentive programs in ten states. George Washington Institute of Public Policy. p. 34. Retrieved from http://gwipp.gwu.edu/files/downloads/GWIPP_Impact10.pdf 26 California Public Utilities Commission. (2009, June). 33% renewables portfolio standard implementation analysis preliminary results. p. 4. Retrieved from http://docs.cpuc.ca.gov/PUBLISHED/GRAPHICS/102354.PDF 27 Sarzynski, A. (2009, November). The impact of solar incentive programs in ten states. George Washington Institute of Public Policy. Retrieved from http://gwipp.gwu.edu/files/downloads/GWIPP_Impact10.pdf

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power plants emit in a single year.28 These ten states are spending money that could be put to better uses to inefficiently reduce carbon emissions.

Studies differ in their claims about how effectively state level incentives increase solar power adoption. A study from the University of Colorado Boulder estimates that the California Solar Initiative (CSI) and its associated rebates were directly responsible for 58 percent of all residential and commercial solar panel installations in California between 2007 and 2012.29 Scientists from Vanderbilt University and Sandia National Laboratories, however, came to a different conclusion after conducting an experiment comparing California’s solar market to a similar market without solar incentives. Their study found that the program had only a modest impact on solar adoption rates.30 While the studies disagree about the effectiveness of the CSI in solar adoption rates, they both agree that the CSI generally increases solar installments. State level incentives can increase solar power adoption, but it is still unclear as to how effectively they do so.

Not only is it unclear how effective the CSI was in solar adoption, but the emissions benefits gained from the program are small relative to the program’s costs. The Boulder study estimates that the CSI only reduced carbon dioxide and nitric oxide emissions by about as much as eliminating one small to mid-sized natural gas power plant.31 Essentially, California taxpayers have spent $437 million on the CSI to close the equivalent of one natural gas power plant (the cleanest burning fossil fuel plant) for 20 years. These small environmental benefits do not justify spending such an exorbitant amount of taxpayer dollars.

NET METERING

Net metering is a state policy that allows residential solar producers to be compensated for surplus power they send back into the electric grid. Electric utilities are required to purchase electricity generated by residential solar arrays. Forty-four states, the District of Columbia, and four U.S. territories have established net metering policies.32 Net metering benefits those who install residential solar panels, but increases the cost of electricity for regular consumers and expands costs to utility companies.

Net metering inflicts mechanical stress on the electric grid and incurs other costs that fall disproportionately on America’s poor. A study conducted by the California Public Utilities Commission estimates that by 2020, costs associated with net energy metering in California alone would be $1.1 billion.33 Utilities are not allowed by most net metering laws to charge solar producers for the added grid stress that results from feeding electricity back into the grid. To compensate for increased costs, utility companies raise electricity prices for everyone. Energy consumers who

28 To determine this, we used the EPA’s Gas Equivalencies . We entered the 6,100,000 metric tons of CO2 into the calculator’s emissions data. The calculator determined that this would be the equivalent of the emissions generated by 1.6 coal-fired power plants in one year. United States Environmental Protection Agency. (n.d.) Equivalencies Calculator. Retrieved from: http://www.epa.gov/cleanenergy/energy-resources/calculator.html#results 29 Hughes, J. E. & Podolefsky, M. (2014, May 6). Getting green with solar subsidies: evidence from the california solar initiative. Retrieved from http://spot.colorado.edu/~jonathug/Jonathan_E._Hughes/Main_files/PV_Subsidies.pdf 30 Zhang, H., Vorobeychik, Y., Letchford, J., Lakkaraju, K. (2015, May). Data-Driven Agent-Based Modeling, with Application to Rooftop Solar Adoption. Retrieved from: http://vorobeychik.com/2015/abmsolar.pdf 31 Hughes, J. E. & Podolefsky, M. (2014, May 6). Getting green with solar subsidies: evidence from the California solar initiative. Retrieved from http://spot.colorado.edu/~jonathug/Jonathan_E._Hughes/Main_files/PV_Subsidies.pdf 32 U.S. Department of Energy. (2015, March). Net Metering. DSIRE. Retrieved from http://ncsolarcen-prod.s3.amazonaws.com/wp- content/uploads/2015/04/Net-Metering-Policies.pdf 33 Energy and , Inc. (2013, September 26). California net energy metering (NEM) draft cost-effectiveness evaluation. p. 6. Retrieved from http://www.cpuc.ca.gov/NR/rdonlyres/BD9EAD36-7648-430B-A692-8760FA186861/0/CPUCNEMDraftReport92613.pdf

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do not have their own solar panels bear the brunt of these raised prices, even though they do not directly contribute to the costs associated with net metering.34 INCENTIVES AT THE NATIONAL LEVEL

The United States government subsidizes solar energy in several ways. The Solar Investment Tax Credit allows owners of residential or commercial solar systems to claim up to 30 percent of the system’s expenditures on their federal taxes. Since the tax credit was enacted in 2006, solar installations have increased at an average of 76 percent per year.35 The tax credit increases solar installments, but it also makes solar dependent on government assistance. The Solar Energy Industries Association expects a 57 percent reduction of installed solar capacity if Congress does not extend the Investment Tax Credit before it expires at the end of 2016.36

Another federal financial incentive is the 1603 Treasury Program, which uses taxpayer dollars to provide capital to start renewable energy projects. The 1603 Treasury Program has granted $7.8 billion for solar projects as of January 5, 2015.37

When government support is withdrawn, solar power falters. In 2008, the Spanish national government withdrew much of its support of solar energy. Since then, more than half of ’s photovoltaic companies have declared bankruptcy.38 Solar power’s dependence on government support illustrates its lack of profitability in an unsubsidized market setting. VERDICT ON ECONOMIC RELIABILITY

Because solar energy is expensive, relies heavily on government assistance, and burdens American taxpayers, it is not yet an economically reliable source of energy. Federal and state governments have spent billions of taxpayer dollars in subsidies to encourage solar power’s development and use, but the benefits of doing so have been minimal. States attempt to increase solar power capacity by implementing RPS, but struggle to meet these mandates even with the help of subsidies. For these reasons, solar power is not a worthwhile investment of taxpayer dollars.

34 Tanton, T. (2014, March). Reforming net metering - Providing a bright and equitable future. p. 7-8. Retrieved from http://alec.org/docs/Net- Metering-reform-web.pdf 35 Solar Energy Industries Association. (2014). Solar investment tax credit (ITC). Retrieved from http://www.seia.org/policy/finance-tax/solar- investment-tax-credit 36 Solar Energy Industries Association. (n.d.) Solar industry data. Retrieved from http://www.seia.org/research-resources/solar-industry-data 37 Overview and Status Update of the §1603 Program. (2015, January 8). Retrieved from http://www.treasury.gov/initiatives/recovery/Documents/STATUS%20OVERVIEW.pdf 38 Gray, A., Clark, P. (2014, July 6). Insurers to cover withdrawal of solar and wind subsidies. The Financial Times. Retrieved from http://www.ft.com/cms/s/0/badcbca0-0386-11e4-817f-00144feab7de.html#axzz3e7FNKeKt

Reliability of Renewable Energy: Solar 9

PHYSICAL RELIABILITY

For solar power to be considered physically reliable, it must consistently meet consumers’ energy demands without causing detrimental effects to grid operations or infrastructure. Solar energy struggles to meet these criteria relative to traditional energy sources. Solar power is inconsistent, inefficient, and cannot consistently meet demand. To mitigate these problems, expensive new transmission infrastructure and grid management techniques would be needed. VARIABILITY OF SOLAR ENERGY EFFICIENCY AND CAPACITY FACTOR

The availability of sunlight is inconsistent, which causes solar power to have a low capacity factor. A capacity factor is a measurement that compares the amount of energy a plant actually produces to the energy that it would produce if operating at full capacity for the same amount of time.39

The median capacity factors for various utility-scale electricity sources are approximated as follows:40

• Photovoltaic 20 percent • Typical onshore 37 percent • Concentrated solar power 38 percent • 45 percent • Combined cycle gas plant 87 percent • Nuclear 90 percent • Enhanced geothermal system 90 percent • Large coal plants 93 percent

Photovoltaic and concentrated solar power have some of the lowest capacity factors of any major energy source. Their low capacity factors indicate that solar resources rarely produce near their full capacity.

LOCATION

Solar energy production is more efficient in areas with a high number of sunny days. Efficiency also increases when sunlight hits the panels more directly. Some solar panels are equipped with a moveable tracking system that allows them to follow the sun through the day, increasing their efficiency.41 Not all panels are equipped to follow the sun, and many places experience indirect sunlight for much of the year, making solar panels less efficient.

Comparing southern California and illustrates the importance of location in solar energy production. Sacramento, California averages 188 clear days and 3,608 hours of sunlight per year,42 compared to Buffalo, New York, which averages 54 clear days and 2,207 hours of sunlight per year.43 A rooftop solar panel system that would produce

39 Capacity Factor. (n.d.). In U.S. Energy Information Administration Glossary. Retrieved from http://www.eia.gov/tools/glossary/index.cfm?id=C 40 Open Energy Index. (n.d.) Transparent cost database - LCOE. Retrieved from http://en.openei.org/apps/TCDB/ 41 Siemens AG. (n.d.). Solar Panels Track the Sun For More Efficiency. Retrieved from http://www.siemens.com/innovation/en/news/2011/solar-panels-track-the-sun-for-more-efficiency.htm 42 Osborn, L. (n.d.). Sunniest US Cities. Retrieved December 14, 2014, from http://www.currentresults.com/Weather-Extremes/US/sunniest- cities.php 43 Current Results. (n.d.) Average annual sunshine in American cities. Retrieved from http://www.currentresults.com/Weather/US/average-

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4,774 kilowatt-hours of electricity a year in Buffalo would produce 6,093 kilowatt-hours a year in Sacramento.44 Solar plants make far more sense in sunny areas, yet they are incentivized and implemented across the United States. IMPLICATIONS FOR THE ELECTRIC GRID WHAT IS THE GRID?

The electric grid includes everything needed to generate and transmit electricity. The American network includes power plants, , and over 450,000 miles of transmission lines.45 Electricity fed into the grid must be consistently supplied to users at the rate it is demanded, because energy cannot be effectively stored for later use. Thus, energy must be generated, transmitted, and used immediately. If too much electricity is supplied, the voltage within the grid becomes unstable, which strains grid infrastructure. Power plants have to decrease their output and they lose money as a result. On the other hand, when too little electricity is supplied, restrictions on the availability of electricity, called brownouts, can occur.46 Because solar power is intermittent and unpredictable, it makes it more difficult for grid operators to maintain this delicate balance between electricity supply and demand.

INTERMITTENCY

The U.S. electric grid is designed to transmit electricity from power plants whose output can be controlled by power grid operators. Solar power is not easily controllable because its fuel source is at the mercy of the weather and cannot be transported. These characteristics necessitate more complex grid management techniques and new grid infrastructure.

Accurate solar forecasting is crucial for the efficient use of solar power. Solar power’s variability is more manageable if power grid operators can anticipate how solar power output is going to change throughout the day. When solar provides less power than was forecasted, grid operators have to ramp backup power plants. Conversely, when solar power provides more power than was forecasted, grid operators have to manually reduce power system output. These practices are costly. To illustrate the importance of accurate forecasting, a study by the NREL on the impact of solar forecasts estimated that improving solar forecasts by 25 percent would save the New England independent system operator $46.5 million in generation costs.47 Methods for include cloud tracking and numerical weather prediction models, which use current weather data to predict future weather patterns.48

Because solar power output varies across all time scales, both long and short term forecasts are used by system operators. For example, an independent system operator in California (CAISO) uses day-ahead and hour-ahead forecasts, and is planning on developing forecasts that predict solar output at 5 minute intervals.49 Solar forecasts will never be completely accurate, but researchers are working to develop more accurate solar power prediction software.

annual-sunshine-by-city.php 44 National Renewable Energy Laboratory. (n.d.) Solar data. Retrieved from http://pvwatts.nrel.gov/pvwatts.php 45 Department of Energy. (2014, November 20). Top 9 things you didn’t know about America’s power grid. Retrieved from http://www.energy.gov/articles/top-9-things-you-didnt-know-about-americas-power-grid 46 Blume, S. (2007). System Basics for the Nonelectrical Professional p. 198-199. Hoboken, New Jersey: John Wiley & Sons, Inc. Retrieved from http://s1.downloadmienphi.net/file/downloadfile6/192/1385055.pdf 47 National Renewable Energy Laboratory. (September 2014). The Impact of Improved Solar Forecasts on Bulk Power System Operations in ISO- NE. pg 1. Retrieve from http://www.nrel.gov/docs/fy14osti/62817.pdf 48 Zhang, J., Hodge, B-M., & Florita, A. (May 2013). Investigating the correlation between wind and solar power forecast errors in the Western Interconnection. p. 2. Retrieved from http://www.nrel.gov/docs/fy13osti/57816.pdf 49 International Energy Agency. (October 2013). Photovoltaic and Solar Forecasting: State of the Art. p. 8. Retrieved from http://iea- pvps.org/index.php?id=3&eID=dam_frontend_push&docID=1690

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Connecting solar plants over large areas can mitigate some of solar power’s variability. Weather patterns are more predictable and stable over larger areas. Aggregating solar plants gives grid operators a larger network of plants from which to draw power, reducing an area’s dependence on backup power plants. If one solar plant suffers from cloud cover, another plant may be available to compensate for some loss of power. The United States Department of Energy states that while aggregating solar would decrease fluctuations in solar power output, there is not yet enough data to accurately quantify the effect that connecting solar plants would have.50

Aggregating multiple power plants also reduces the need for reserves, regardless of the type of generation. For example, the Midwest Independent Transmission System Operator, Inc. consolidated 26 balancing authorities, which are organizations that balance electricity supply and demand within a specific area. This consolidation decreased reserve capacity needs over the areas covered from 1,200 megawatts to 400 megawatts.51

GRID IMBALANCES

If aggregating multiple solar facilities is not feasible, operating reserves can be called upon to provide power when solar fails.52 But most traditional power plants are designed to provide a steady baseload of energy and are unequipped to ramp up and down quickly to compensate for solar power’s variability. Increasing cycling to compensate for inconsistent solar results in higher operation and maintenance costs for conventional power plants.53

During peak solar hours electricity demand is low, and the combined generation of solar and baseload power plants can frequently produce more energy than is needed, leading to problems with overgeneration.54 Certain power plants, called baseload generators, must always be running at a minimum output to meet reliability criteria or to fulfill basic energy demands. When solar power plants produce too much electricity, grid system operators have to order them to decrease their output so that electricity supply and demand can be balanced.55 Curtailments and the resulting financial losses become more common as more solar-generated electricity is integrated into the grid.56

Figure 4 demonstrates the magnitude of solar power’s overgeneration problem. The “” shows the amount of energy that the traditional power plants of the California Independent System Operator will have to supply on a typical day in March.57 During the day, when solar plants are most productive, demand for electricity from traditional power plants plummets. In the evening, the need for traditional power increases due to the combined effect of solar output decreasing and energy demand increasing. Existing traditional power plants are expected to make up the difference, but most of these older plants require several hours to ramp up sufficiently. Fossil-fueled plants historically have been built to provide constant power, and it is difficult for them to meet increased demand on such short notice.58

50 U.S. Department of Energy. (2011, May.) The Role of Large Balancing Areas in Integrating Solar Generation. Retrieved from http://www1.eere.energy.gov/solar/pdfs/50059.pdf 51 Ibid. 52 National Renewable Energy Laboratory. (2013, September 24). NREL calculates emissions and costs of power plant cycling necessary for increased wind and solar in the West. Retrieved from http://energy.gov/eere/articles/energy-department-report-calculates-emissions-and- costs-power-plant-cycling-necessary 53 Ibid. 54 Trabish, H. K. (2014, October 22.) The 'epic fail' on solar's doorstep—and how the grid can help. Retrieved from http://www.utilitydive.com/news/the-epic-fail-on-solars-doorstepand-how-the-grid-can-help/324411/ 55 Howarth, D., Monsen, B. (n.d.) Renewable energy faces daytime curtailment in California. Retrieved from http://www.nawindpower.com/issues/NAW1412/FEAT_04_Renewable-Energy-Faces-Daytime-Curtailment-In-California.html 56 Trabish, H. K. (2014, October 22.) The 'epic fail' on solar's doorstep—and how the grid can help. Retrieved from http://www.utilitydive.com/news/the-epic-fail-on-solars-doorstepand-how-the-grid-can-help/324411/ 57 Smith, O., Bell, M. (2013, October 29.) Renewables’ bird problem. Retrieved from http://blog.rmi.org/blog_2013_10_29_renewables_bird_problem 58 Ibid.

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As seen in Figure 4, the problem of overgeneration and increased ramping needs are expected to worsen in the coming years as mandates and incentives for renewable energy continue to increase the use of solar.

FIGURE 4. THE DUCK CURVE SHOWING RAMPING NEEDS AND OVERGENERATION RISK. 59

Solar power’s intermittency makes it a difficult energy source for grid operators to balance with electricity demand. Aggregating multiple solar plants can help mitigate solar power’s intermittency, but it is expensive to do and not all solar facilities are close enough to each other for aggregation to be feasible. In other cases, traditional energy sources can back up solar when the sun is not shining but many of these facilities are not built to handle the ramping requirements as more solar power is integrated into the grid. No matter the method used, reducing solar power’s intermittency is costly.

USING ENERGY STORAGE

The for energy often occurs in the evening when solar power is least productive and cannot reliably meet demand.60 The inconsistency of solar energy could be alleviated through energy storage, but because traditional fuel sources can be utilized any time of the day or year, commercial-scale energy storage is uncommon.

59 California Independent System Operator. (2013.) What the duck curve tells us about managing a green grid. p.3 Retrieved from http://www.caiso.com/documents/flexibleresourceshelprenewables_fastfacts.pdf 60 U.S. Energy Information Administration. (2011, April 6). Demand for electricity changes throughout the day. Retrieved from http://www.eia.gov/todayinenergy/detail.cfm?id=830

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Different types of energy storage would be needed to accommodate solar energy’s variability at different timescales.61 On short timescales, grid operators would need to utilize low-capacity, fast-response storage. Some fast-response storage possibilities include batteries, flywheels (which store energy as momentum in spinning disks), and high-energy capacitors (which store energy in the form of an electrostatic field between its two conducting plates). 62 For unpredictable weather patterns that occur on long timescales, high-capacity and slower-response storage would be needed. Slower-response storage possibilities include pumped hydroelectric storage and compressed air energy storage.63

Because it is uncommon, regulatory uncertainty surrounds grid-level energy storage. Utility companies hesitate to invest in energy storage because it is difficult to estimate how the government will regulate energy storage projects and how those regulations will affect profits.64 In 2013, the California Public Utilities Commission approved a mandate requiring 1.3 gigawatts of energy storage to be added to the grid by 2020.65 In an effort to reach this goal, one utility company, Southern California Edison, has invested $50 million to develop 8 megawatts of power storage with - ion batteries.66 Southern California Edison has warned that California’s energy storage mandate "could cost up to $3 billion with uncertain net benefits for customers."67

NET METERING

When private owners of small scale solar systems produce more power than they can use, their surplus power is fed back into the grid and purchased by electricity utilities. Because the grid was designed for one-directional flow rather than two-directional flow, accepting electricity from consumers places undue stress on the grid.68 In , where solar power installations have experienced rapid growth, subsidies for rooftop solar had to be cut in half when residential solar production began destabilizing the power grid. Solar power’s intermittency caused fluctuation in grid that made areas vulnerable to blackouts.69 Additionally, officials at the California Independent System Operator say renewable energy producers make management of the California grid more complex. Bob Foster, mayor of Long Beach and a member of the system operator board, said, "We are getting to the point where we will have to pay people not to produce power."70

61 American Physical Society. Integrating renewable electricity on the grid. p.16. Retrieved from http://www.aps.org/policy/reports/popa- reports/upload/integratingelec.pdf 62 U.S. Energy Information Administration. (2011, December 14.) Electricity storage can be used for energy management and power quality. Retrieved from http://www.eia.gov/todayinenergy/detail.cfm?id=4310 63 Ibid. 64 American Physical Society. Integrating renewable electricity on the grid. p.19. Retrieved from http://www.aps.org/policy/reports/popa- reports/upload/integratingelec.pdf 65 St. John, J. (2013, October 27.) California passes huge mandate. Retrieved from http://www.greentechmedia.com/articles/read/california-passes-huge-grid-energy-storage-mandate 66 Macgill, Bobby. (2015, January 15). California Takes in Developing Energy Storage. Discovery News. Retrieved from http://news.discovery.com/earth/california-takes-lead-in-developing-energy-storage-150115.htm 67 Halper, E. (2013, December 2.) Power struggle: Green energy versus a grid that's not ready. Los Angeles Times. Retrieved from http://articles.latimes.com/2013/dec/02/nation/la-na-grid-renewables-20131203#axzz2mXIfGQrx 68 Ferber, D. (2013, March 5). Can the grid handle distributed renewable energy? Retrieved from: http://midwestenergynews.com/2013/03/05/can-the-grid-handle-distributed-renewable-energy/ 69 Carducci, A. (2013, January 11.) Hawaii Cuts Back on Solar Power Subsidies. Retrieved from http://news.heartland.org/newspaper- article/2013/01/11/hawaii-cuts-back-solar-power-subsidies 70 Halper, E. (2013, December 2.) Power struggle: Green energy versus a grid that's not ready. Los Angeles Times. Retrieved from http://articles.latimes.com/2013/dec/02/nation/la-na-grid-renewables-20131203#axzz2mXIfGQrx

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THE NEED FOR LONG-DISTANCE TRANSMISSION

The U.S. electric grid was designed to supply power at the local and regional level. But, with the exception of Southern California, the areas with the greatest solar potential are located far from densely populated areas on the coasts. Figure 5 displays the availability of solar energy in the United States.

FIGURE 5. PHOTOVOLTAIC SOLAR RESOURCES OF THE UNITED STATES.71

Because solar power plants are generally located far from population centers, they necessitate the construction of long-distance transmission lines. A study by GE Energy concluded that integrating 30 percent wind and solar power would cost $13.7 billion in transmission costs for the PJM Interconnection, a large transmission system that brings power to 13 eastern states and the District of Columbia.72 Similarly, in 2009 the California Public Utilities Commission estimated that meeting the state’s 2010 and 2020 renewable energy requirements would cost $16 billion in transmission infrastructure alone.73

71 National Renewable Energy Laboratory. (2013, September 3.) Solar maps. Retrieved from http://www.nrel.gov/gis/solar.html 72 PJM Interconnection. (2014, February 14.) Executive summary of renewable integration study for PJM. Retrieved from http://www.google.com/url?q=http%3A%2F%2Fwww.pjm.com%2F~%2Fmedia%2Fcommittees- groups%2Fcommittees%2Fmic%2F20140303%2F20140303-pris-pjm-cover- letter.ashx&sa=D&sntz=1&usg=AFQjCNE5f_6bzHY2fBbqIFcTt4yDzKYfkw 73 California Public Utilities Commission. (June 2009). 33% Percent Renewables Portfolio Standard Implementation Analysis Preliminary Results. Retrieved from http://docs.cpuc.ca.gov/PUBLISHED/GRAPHICS/102354.PDF

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Despite these high costs, in recent years levels of investment in electricity transmission have reached record highs.74 Part of this growth is attributed to efforts to connect remote sources of wind and solar power to the grid.75 A high- voltage transmission project called SunZia, for example, will span 515-miles and cost $2.2 billion. The SunZia line is just one of several transmission projects being developed to move wind and solar power through Arizona, Colorado, New Mexico, and Utah. Together these projects will cost over $6 billion to build, in addition to the $20 billion needed to build the renewable power plants. Developers count on these projects becoming more economically feasible in the future as new federal carbon regulations are passed. Developers also predict that more aggressive RPS in western states will lead to an increased demand for renewable energy and long distance transmission.76

TECHNICAL CHALLENGES OF LONG-DISTANCE TRANSMISSION

Because remotely-located energy sources require long-distance transmission, scientists are looking for ways to improve long-distance transmission capabilities. Currently, electricity is transmitted as (AC). Physicists at the American Physical Society suggest using (DC) for long-distance transmission to reduce electricity loss.77

Since electricity is generated and used as AC, power would have to be converted from AC to DC for transmission and then back to AC for consumers. The process of long-distance DC transmission and conversion between AC and DC could result in electrical losses of up to ten percent. To minimize these losses, the voltage can be increased. Such high voltages, however, make it more difficult for semiconductors to convert electricity between AC and DC, which drives up the cost of transmission. Long-distance DC transmission will raise costs because it will require the construction of semiconductors that convert electricity between AC and DC and new high voltage DC transmission infrastructure.78 While utilizing DC would make long-distance transmission more efficient and feasible, it would do so at a high cost. VERDICT ON PHYSICAL RELIABILITY

Because solar power is intermittent and inefficient, it increases the need for backup power plants. Solar power is also commonly generated in remote locations, far from high electricity demand. Making solar power reliable would require expensive investments in grid-level energy storage and transmission infrastructure. The current costs of making solar power physically reliable outweigh its limited benefits.

74 Edison Electric Institute. (2015, January 8). Actual and Planned Transmission Investment By Shareholder-Owned Utilities (2008–2017). Retrieved from http://www.eei.org/issuesandpolicy/transmission/documents/bar_transmission_investment.pdf 75 U.S. Energy and Information Administration (2014, August 26) Investment in electricity transmission infrastructure shows steady increase. Retrieved from http://www.eia.gov/todayinenergy/detail.cfm?id=17711 76 Robinson-Avila, K. (2015, June 21). SunZia’s $2B dream still a gamble. Albuquerque Journal. Retrieved from http://www.abqjournal.com/601834/news/sunzias-2b-dream-still-a-gamble.html 77 American Physical Society. (2010). Integrating Renewable Electricity on the Grid: A Report by the APS Panel on Public Affairs. Retrieved from http://www.aps.org/policy/reports/popa-reports/upload/integratingelec.pdf 78 American Physical Society. (2010). Integrating Renewable Electricity on the Grid: A Report by the APS Panel on Public Affairs. p. 22-23. Retrieved from http://www.aps.org/policy/reports/popa-reports/upload/integratingelec.pdf

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ENVIRONMENTAL RELIABILITY

An alternative energy source must have fewer environmental impacts than traditional fossil fuels to be considered environmentally reliable. According to this definition, solar power is environmentally reliable, but this report also finds that solar power’s edge over fossil fuels is not as pronounced when all environmental costs are considered. Although solar power does not emit greenhouse gases during electrical production, its environmental benefits are diminished by its water usage in arid regions, its need for fossil fuel backup reserves, the pollution caused by the PV panel manufacturing process, and its impact on wildlife populations. WATER

Solar power plants utilize water for cooling and cleaning purposes. The construction and maintenance of solar facilities also require large volumes of water. The construction of utility-scale PV projects requires nearly 400 million gallons of water. Maintenance tasks, such as washing dust from the panels, require an additional 7 million gallons of water each year.79 Overall, PV plants have an estimated lifetime water consumption rate of 520 gallons per megawatt-hour for typical panels.80 According to a study done by the International Energy Agency, the water withdrawal and consumption rates of PV plants are below those of coal, natural gas, and nuclear plants.81

CSP plants, however, commonly use more water than PV plants. The biggest water consumption in CSP plants occurs when steam exiting the turbines is cooled. Wet-cooling technology is the most commonly found cooling system in CSP plants. CSP plants that use wet-circulation cooling systems use an estimated 1,240 gallons of water per megawatt- hour, but dry-cooling systems are gaining popularity to limit water consumption.82

WET-CIRCULATION VS DRY-COOLING

In wet-circulation systems, the heated water is spread out over a large surface area and exposed to cooler water. As the heated water cools, a small portion of the water is lost through evaporation while the remainder is reused.83 Although wet-cooling is used in coal, nuclear, and natural gas plants, CSP power plants with wet-circulation cooling systems require more water per unit of electricity generated than traditional fossil fuel facilities using the same technologies.84 Unfortunately, solar plants are most often constructed in areas with high temperatures, high sun exposure, and most importantly, scarce water supplies. CSP plants compete for water with agricultural users, local municipalities, and wildlife.

79 Mulvaney, D. (2014, August 26). Solar energy isn’t always as green as you think. Retrieved from http://spectrum.ieee.org/green- tech/solar/solar-energy-isnt-always-as-green-as-you-think We converted the numbers given in liters to gallons by multiplying the number of liters by 0.264172. 80 Keith, G., Jackson, S., Napoleon, A., Comings, T., Ramey, J. A. (2012, September 19). The hidden costs of electricity. 62. Prepared for The Civil Society Institute. Retrieved from http://www.civilsocietyinstitute.org/media/pdfs/091912%20Hidden%20Costs%20of%20Electricity%20report%20FINAL2.pdf 81 International Energy Agency. (2012). Water for energy - Is energy becoming a thirstier resource? p. 10. Retrieved from http://www.iea.org/media/weowebsite/2012/WEO_2012_Water_Excerpt.pdf 82 Keith, G., Jackson, S., Napoleon, A., Comings, T., Ramey, J. A. (2012, September 19).The hidden costs of electricity. p. 62. Prepared for The Civil Society Institute. Retrieved from http://www.civilsocietyinstitute.org/media/pdfs/091912%20Hidden%20Costs%20of%20Electricity%20report%20FINAL2.pdf 83 Union of Concerned Scientists. (2013, March 5). Environmental impacts of solar power. Retrieved from http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-solar-power.html#.VLBdD2TF-mm 84 Carter, N. T., Campbell, R. J. (2009, June 8). Water issues of concentrating solar power (CSP) electricity in the U.S. southwest. Prepared for Congressional Research Service. Retrieved from http://www.circleofblue.org/waternews/wp-content/uploads/2010/08/Solar-Water-Use- Issues-in-Southwest.pdf

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In efforts to reduce the stress on local water supplies, developers in , Arizona, California, and Nevada have been driven to use dry-cooling systems.85 Rather than relying on water to cool the steam exiting turbines, dry-cooling systems expose the steam to the cooler outside air to condense the steam. Dry-cooling systems can decrease power plant water consumption by around 90 percent.86 Solar power, however, is already intermittent and expensive, and switching to dry cooling results in a 7 percent drop in electricity production and a 10 percent increase in capital costs.87

The drop in electricity production and increased costs are further exacerbated by the hot and arid locations that most CSP plants tends to be built in. Dry-cooling systems require a significant difference between the temperature of the exhaust steam and the outside air to condense steam back into water, and, as a result, dry-cooling technology is much less effective in locations with temperatures consistently above 100 degrees Fahrenheit.88 This means that CSP plants in the hot and arid southwest will run even less efficiently using dry-cooling systems. Water usage is greatly decreased, but less power is produced than normal, making solar power even less physically reliable. EMISSIONS

When solar energy is integrated into a power system, grid operators cycle conventional power plants to compensate for decreases in solar power output. Cycling conventional power plants increases the plant’s emissions per unit of electricity produced, negating some of solar power’s environmental benefits.89 A 2013 study completed by the National Renewable Energy Laboratory (NREL), however, concluded that the added carbon emissions caused specifically by cycling are "negligible" when compared to the carbon reductions from using wind and solar.90

Solar power has emission costs beyond those caused by cycling. Manufacturing, transportation of materials, installation and construction, maintenance, and the decommissioning of solar-power facilities also contribute to solar power’s net . These emissions all contribute to the cycle emissions of solar, which is an assessment of the total carbon emissions produced over a solar plant’s life.91

Figure 6 shows the results from an NREL study comparing the life cycle greenhouse gas emissions of various energy sources. Other sources of energy emit more greenhouse gases over their lifetime compared to solar energy.

85 Union of Concerned Scientists. (2011, November). Freshwater use by US power plants. 2. Retrieved from http://www.ucsusa.org/sites/default/files/attach/2014/08/ew3-freshwater-use-by-us-power-plants-exec-sum.pdf 86 Union of Concerned Scientists. (2013, March 5). Environmental impacts of solar power. Retrieved from http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-solar-power.html#.VLBdD2TF-mm 87 International Renewable Energy Agency. (2013, January). Concentrating solar power. 12. Retrieved from http://www.irena.org/DocumentDownloads/Publications/IRENA-ETSAP%20Tech%20Brief%20E10%20Concentrating%20Solar%20Power.pdf 88 Union of Concerned Scientists. (n.d.) Environmental impacts of solar power. Retrieved from http://www.ucsusa.org/clean_energy/our-energy- choices/renewable-energy/environmental-impacts-solar-power.html#.VcJ2XBNVhBc 89 National Renewable Energy Laboratory. (n.d.) Impacts on conventional generators. Retrieved from http://www.nrel.gov/analysis/key_activities_integ_impacts.html 90 National Renewable Energy Laboratory. (2013, September 24). NREL calculates emissions and costs of power plant cycling necessary for increased wind and solar in the West. Retrieved from http://www1.eere.energy.gov/wind/pdfs/55588.pdf 91 Union of Concerned Scientists. (2013, March 5). Environmental impacts of solar power. Retrieved January 5, 2015, from http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-solar-power.html#.VLBdD2TF-mm

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FIGURE 6. LIFE CYCLE GREENHOUSE GAS EMISSIONS FOR VARIOUS ENERGY SOURCES.92

Although the emissions from cycling and other parts of a solar panel’s life negate some of its environmental benefits, solar power plants have significantly fewer emissions over their lifetime than conventional power plants. MANUFACTURING, RECYCLING, AND FOREIGN POLLUTION

Potentially harmful substances such as silicon tetrachloride, hydrochloric acid, and hydrofluoric acid are used in the production of solar panels.93 When waste products from solar panel manufacturing are improperly disposed of, they may harm human health and contaminate the environment. Facilities in have caused health problems for residents by dumping chemical wastes used to manufacture solar panels in rivers and fields near their facilities. Local residents have experienced inflamed eyes and throats, and polluted waterways have killed fish and livestock. The of these areas has also been poisoned, making future difficult.94

China is currently the world’s leader in PV panel manufacturing, accounting for over 60 percent of global production.95 Chinese manufacturing, per panel produced, has a carbon footprint that is twice as large as Europe’s solar panel manufacturing process.96 95 percent of Chinese panels are exported to other countries, but China is left with the pollution.97 Europe, , and the United States continue to claim solar power is environmentally friendly, but these countries do not pay the full environmental costs of the manufacturing process.

92 National Renewable Energy Laboratory. (2014, July 21). Life cycle assessment harmonization results and findings. Retrieved from http://www.nrel.gov/analysis/sustain_lca_results.html 93 Galland, A. (2012). Clean & green: Best practices in photovoltaics. 21. Retrieved from http://www.clca.columbia.edu/Clean&Green- Photovoltaics.pdf 94 Mulvaney, D. (2014, August 26). Solar energy isn’t always as green as you think. Retrieved from http://spectrum.ieee.org/green- tech/solar/solar-energy-isnt-always-as-green-as-you-think 95 Ramzy, A. (2014, June 2). China's Solar Panel Production Comes at a Dirty Cost. Retrieved from http://sinosphere.blogs.nytimes.com/2014/06/02/chinas-solar-panel-production-comes-at-a-dirty-cost/ 96 Lerner, L. (2014, May 29). Solar panel manufacturing is greener in Europe than China, study says. Retrieved from http://www.anl.gov/articles/solar-panel-manufacturing-greener-europe-china-study-says 97 Worldwatch Institute. (November 2012). ’s : A Market Analysis of Phase 1. Retrieved from http://www.worldwatch.org/system/files/WW%20Research%20Note%20India%20Solar%20Market%20Analysis%20Phase%201_FINAL_0.p df

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At the end of a solar panel's life cycle, it can be recycled into a product almost as efficient as new solar panels. The recycling process reduces the environmental burden of the demand for new materials.98 Solar panel recycling is limited, however, because there are not yet enough obsolete solar panels to make recycling economically viable.99 Until recycling solar panels becomes economically viable, expanding the solar industry will continue to result in Chinese manufacturing and its associated environmental harms. WILDLIFE IMPACTS

CSP and PV plants infringe on wildlife habitat and harm or displace threatened species because of the large amount of undeveloped they require. The , located in the in California, occupies the habitats of numerous protected species, including the San Joaquin kit fox, the golden eagle, and the giant kangaroo rat. The Topaz solar plant’s project developers have negotiated with the United States Fish and Wildlife Service to develop a conservation plan that minimizes the impacts of the Topaz solar plant on these wildlife populations.100 The Ivanpah Solar Farm, located in the Mojave , has displaced 144 desert tortoises. The desert tortoise is on the threatened species list and is the state reptile of Nevada and California.101 BrightSource Energy, the developer of the Ivanpah Solar Farm, has had to spend over $56 million capturing the displaced tortoises and reintroducing them safely into the wild.102

In CSP tower systems, the concentrated heat and large cooling towers can affect birds as they fly through the solar plants. When birds see the reflective surfaces of a solar plant they often confuse them for a body of water and fly towards them.103 Jeff Holland, a representative of Ivanpah, officially reported 321 bird or bat fatalities over a 6-month period, many of which were caused by impacts with solar towers or singeing from concentrated heat.104 233 Yuma clapper rails, an endangered bird, have been found on three other solar plants in the California desert. Because this species is endangered, concerned conservation groups have threatened to sue the federal government if government agencies do not more fully evaluate future solar plants’ potential bird impacts.105

Efforts by the EPA and California lawmakers may decrease these wildlife impacts. The EPA has recently identified at least 80,000 abandoned sites and other contaminated that can be used for the construction of future renewable energy plants.106 The EPA provides information and technical support for those who are trying to reuse these abandoned mining sites.107

98 Bine Informationsdienst. (n.d.) Recycling photovoltaic modules. Retrieved from http://www.bine.info/fileadmin/content/Publikationen/Englische_Infos/projekt_0210_engl_internetx.pdf 99 Nunez, C. (2014, November 11). How Green Are Those Solar Panels, Really?. National Geographic. Retreived from http://news.nationalgeographic.com/news/energy/2014/11/141111-solar-panel-manufacturing--ranking/ 100 Moler, Robert. (14, May 2015) Wildlife and Creating Renewable Energy on the Carizzo Plain. Sacramento Fish and Wildlife Office. Retrieved from http://www.fws.gov/sacramento/outreach/Featured-Stories/RenewableEnergy-CarrizoPlain/RenewableEnergy-CarrizoPlain.htm 101 U.S. Fish and Wildlife Service. Desert tortoise (Gopherus agassizii). Retrieved from http://ecos.fws.gov/speciesProfile/profile/speciesProfile?spcode=C04L 102 Wells, K. (2012, October 10). Where Tortoises and Solar Power Don't Mix. Retrieved from http://www.bloomberg.com/bw/articles/2012-10- 04/where-tortoises-and-solar-power-dont-mix 103 Uptown, John. (27, August 2014). Solar Farms Threaten Birds. Scientific American. Retrived from http://www.scientificamerican.com/article/solar-farms-threaten-birds/ 104 Kraemer, S. (2014, September 3). For the Birds: How Speculation Trumped Fact at Ivanpah. Retrieved from http://www.renewableenergyworld.com/rea/news/article/2014/09/for-the-birds-how-speculation-trumped-fact-at-ivanpah 105 Uptown, John. (27, August 2014). Solar Farms Threaten Birds. Scientific American. Retrived from http://www.scientificamerican.com/article/solar-farms-threaten-birds/ 106 Environmental Protection Agency. (2011, December 1). Shining Light on a Bright . p. 11. Retrieved from http://www.epa.gov/aml/revital/amlsolarfact.pdf 107 Page, Samantha. (28, April 2015). California Wants To Make it Easier to Cover Old Mines With Renewable Energy. ThinkProgress. Retrived from http://thinkprogress.org/climate/2015/04/28/3652072/californias-mines-are-going-solar/

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Furthermore, a California bill was passed in April of 2015 which allows solar and wind projects that are built on mining sites to forego the expensive and time-consuming environmental reviews that solar and wind projects usually require. The bill’s author expects that the bill will encourage more solar projects to be built on already-used land rather than pristine desert.108 VERDICT ON ENVIRONMENTAL RELIABILITY

Governments and individuals pursue solar power because they view it as an environmentally friendly electricity source. Solar power does reduce greenhouse gas emissions, but it still relies heavily on fossil fuels for backup power. Solar plants are usually built in where increased water usage strains local water supply. Because solar panel producers rely heavily on Chinese manufacturing, China bears the brunt of solar pollution. Utility scale solar plants require large areas, negatively impacting local wildlife and their habitats. Solar has environmental benefits, but its hidden environmental costs make it a less environmentally reliable energy source than most people believe.

108 Ibid.

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CASE STUDY: SOLAR ENERGY IN GERMANY

In Germany, a government program and social movement called the Energiewende (roughly translated as “energy revolution”) pushes German electricity consumers toward reliance on solar generation. The Energiewende began in the 1970s as a movement against nuclear energy and was strengthened by both the Chernobyl accident in 1986 and the Fukushima earthquake in 2011. Today, the Energiewende is a government movement to boost renewable energy sources, reduce dependence on neighboring countries for fossil fuels, and move away from the perceived threat of nuclear energy. The German government also asserts that solar energy and other renewable energy sources will improve local economies.109 Now, many people view Germany as the international standard of solar energy production. Germany's intensive solar incentives have boosted its solar industry more quickly than other countries, but this boom has proven to be unreliable and economically unstable. What appears to be a simple story of implementing an environmentally friendly energy source is more complex than it appears. EXAGGERATED CLAIMS OF GERMAN SOLAR POWER

On the afternoon of June 9, 2014, German solar energy plants produced 23.1 gigawatts of energy between 1:00 and 2:00 pm, which amounted to 50.6 percent of the country’s energy demand for that time.110 But overall, solar electricity met only 20.9 percent of that day’s total electricity demand.111 Furthermore, because that day was a national holiday, offices and factories were closed, making electricity demand unusually low. And so, what might have been an average output of solar power broke a record for solar energy production.112

Solar power did produce a significant amount of electricity in the summer, but solar power performed less admirably the rest of the year. On January 18, 2014, Germany produced only 0.1 percent of that day’s electricity demand from solar power. 113 These examples illustrate how solar power advocates can exaggerate solar power's success by handpicking their facts. The big picture shows a less attractive side of solar. ECONOMIC RELIABILITY

Solar power’s costs are heavier than most people think. Estimates show that German taxpayers paid $23 billion for solar energy that has a market value of less than $4 billion. On Germany’s solar investment, Colin Vance, from the German economic research institute RWI, said, “The least competitive renewable energy is getting the most support,” he said. “There is a certain insanity to it, yes.”114

From 1998 to 2015, Germany’s residential electricity prices rose by about 50 percent. In 2013, German electricity cost around 29 cents per kilowatt-hour.115 For comparison, residential electricity in the United States in May, 2015 costs

109 Heinrich Böll Foundation. (n.d.). Why the Energiewende. Retrieved from http://energytransition.de/ 110 Luntz, S. (2014, June 14.) Germany now produces half of its energy using solar. Retrieved from http://www.iflscience.com/technology/germany-now-produces-half-its-energy-using-solar 111 Wilson, R. (2014, August 8). Reality check: Germany does not get half of its energy from solar panels. Retrieved from http://theenergycollective.com/robertwilson190/456961/reality-check-germany-does-not-get-half-its-energy-solar 112 Luntz, S. (2014, June 14.) Germany now produces half of its energy using solar. Retrieved from http://www.iflscience.com/technology/germany-now-produces-half-its-energy-using-solar 113 Wilson, R. (2014, August 8). Reality check: Germany does not get half of its energy from solar panels. Retrieved from http://theenergycollective.com/robertwilson190/456961/reality-check-germany-does-not-get-half-its-energy-solar 114 McGrath, M. (2013, July 9). Can Germany its ‘energy bender’ shift to green power? BBC News. Retrieved from http://www.bbc.com/news/science-environment-23127175 115 Weiss, J. (2014, July). Solar Energy Support in Germany: A Closer Look. SEIA. Retrieved from: http://www.seia.org/research- resources/solar-energy-support-germany-closer-look

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about 13 cents per kilowatt-hour.116 High retail electricity costs in Germany are due in part to investments in renewable energy like solar.117

In recent years, Germany has been phasing out solar subsidies that it cannot afford to sustain. In 2012, the German Environmental Minister conceded that while solar energy is a desired goal for Germany’s energy portfolio, “the cost factor has to be at acceptable levels.”118 Germany’s solar subsidies have incentivized solar power installations, but at an unsustainably high cost.

The German government is not alone in paying large sums of money on behalf of solar power. Because solar power is intermittent, traditional electricity producers have had to make substantial changes to their plants to handle the fluctuating electricity demands. RWE, a German electricity company, has invested 700 million Euros (833 million 2015 U.S. dollars) to adapt their (soft coal) plants to the changing energy demands.119 Ulrich Hartmann, executive vice president of RWE, said, “Back in the days, our lignite plants were inflexible, produced power around the clock and were always earning money. Now they are as flexible as gas plants.”120

Solar power has proven to be an expensive form of energy for the German government and energy companies. The fiscal issues surrounding German solar subsidies and high energy prices compound to create a dismal outlook for the German solar market. PHYSICAL RELIABILITY

Solar energy production in Germany is illogical because of the country's low solar resources. Figure 7 shows solar potential in the United States compared to Spain and Germany.

116 U.S. Energy Information Administration. (2015, July 27). Electric power monthly. Retrieved from http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_5_6_a 117 Weiss, J. (2014, July). Solar Energy Support in Germany: A Closer Look. SEIA. Retrieved from: http://www.seia.org/research- resources/solar-energy-support-germany-closer-look 118 Connolley, Kate. (2, March 2012). Germany to cut solar power subsidies. The Guardian. Retrieved from http://www.theguardian.com/world/2012/mar/02/germany-cuts-solar-power-subsidies 119 Mengewein, J. (2014, July 30). German Utilities Bail Out Electric Grid at Wind's Mercy. Retrieved from http://www.bloomberg.com/news/articles/2014-07-24/german-utilities-bail-out-electric-grid-at-wind-s-mercy 120 Ibid.

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FIGURE 7. SOLAR RESOURCES IN THE UNITED STATES, SPAIN, AND GERMANY.121

The irony is blatant–solar energy potential in Germany is comparable to solar potential in Alaska, yet solar energy was and still is heavily incentivized by the German government. The German government has managed to achieve high solar penetration in Germany by incentivizing household PV systems, which are less expensive than CSP plants for both utility companies and the government.122 ENVIRONMENTAL RELIABILITY

One of the reasons Germany has focused on building up its renewable energy portfolio is to lessen its dependency on neighboring countries for fossil fuels. But solar installations do not eliminate the need for fossil fuels because solar power must be backed up by other energy sources, which are often fossil fuels.123

121 Roberts, B. J. (2009, November 23). Photovoltaic solar resource: The United States of America, Spain and Germany. National Renewable Energy Laboratory. Retrieved from http://www.gosolarsantafe.com/solar-radiation-map 122 Wirth, H. (2015, May 19). Recent facts about photovoltaics in Germany. Fraunhofer Institute for Solar Energy Systems. p. 33. Retrieved from http://www.ise.fraunhofer.de/en/publications/veroeffentlichungen-pdf-dateien-en/studien-und-konzeptpapiere/recent-facts-about- photovoltaics-in-germany.pdf 123 Energy Transition: The German Energiewende. (2015, February 19). How is Germany integrating and balancing renewable energy today?

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From 1990 to 2012, Germany has reduced its emissions by 24.7 percent.124 Germany’s emissions from electricity production contribute to a combined emissions cap that the entire European Union is supposed to stay under.125 So, while Germany might be limiting their emissions, this allows countries like and to produce more energy with much cheaper coal. Despite the vast amounts of money and labor Germany has spent in efforts to reduce emissions, there is no net change in emissions for the European Union as a whole.126

Countries pursue renewable sources of energy to reduce greenhouse gas emissions and environmental impacts. Unfortunately, even with the money Germany has invested in solar energy, the environment is only marginally cleaner, if at all. In its entirety, Germany’s solar-energy production will cut carbon dioxide emissions in Germany by only one percent over the next 20 years – in other words, as explained by Bjørn Lomborg, director of the Copenhagen Consensus Center, “By the end of the century, Germany’s $130 billion solar panel subsidies will have postponed temperature increases by 23 hours.”127 GERMAN SOLAR POWER ANALYSIS

Other countries extol Germany's successes with solar power, but upon closer inspection, Germany’s solar progress is less spectacular than it initially appears. Germany has invested billions of dollars in solar energy over several decades, but its solar subsidies were unsustainable and have neither decreased emissions nor made Germany independent of other countries for fossil fuels. Germany’s solar experience reveals that solar power’s limited benefits do not outweigh its prohibitively high costs.

Retrieved from: http://energytransition.de/2015/02/how-germany-integrates-renewable-energy/ 124 Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety. (2014, January 16.) Hendricks strives for more ambitious targets. [Press Release]. Retrieved from http://www.bmub.bund.de/en/press/press-releases/detailansicht- en/artikel/hendricks-beim-klimaschutz-ehrgeiziger-werden/?tx_ttnews%5BbackPid%5D=114 125 European Commission. (2015, July 15). The EU System (EU ETS). Retrieved from: http://ec.europa.eu/clima/policies/ets/index_en.htm 126 Lomborg, B. (2012, February 18). Goodnight sunshine. Slate. Retrieved from http://www.slate.com/articles/news_and_politics/project_syndicate/2012/02/why_germany_is_phasing_out_its_solar_power_subsidies_.ht ml 127 Lomborg, B. (2012, February 18). Goodnight sunshine. Slate. Retrieved from http://www.slate.com/articles/news_and_politics/project_syndicate/2012/02/why_germany_is_phasing_out_its_solar_power_subsidies_.ht ml

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CONCLUSION

Solar power remains an expensive form of energy generation compared to fossil fuels, requiring extensive state and federal subsidies to incentivize its use. States also mandate the use of solar power through renewable portfolio standards, but have had difficulty attaining those standards even after spending billions of dollars incentivizing and integrating renewable energy. Because the solar industry is dependent on these mandates and subsidies, it is an an economically unreliable energy source. For how little emission benefits solar power has provided, it is not a worthwhile investment of taxpayer dollars.

Solar energy is physically unreliable because it is inconsistent and inefficient. The sun is not always shining, so solar plants cannot always produce power. As a result, utilizing solar energy is an inefficient way to produce electricity and is dependent on more reliable energy sources like coal and natural gas for backup power.

Because solar power is intermittent and remotely located, our current grid infrastructure is ill-equipped to integrate significant amounts of solar power into the United States power system. Even rooftop solar causes energy congestion problems and complicates the management of electric grids. Improved solar forecasting, grid-level energy storage, the aggregation of multiple solar plants, and new transmission lines may make solar power more physically reliable in the future, but utilizing these technologies would cost billions of dollars and it is difficult to evaluate the costs and benefits of incorporating them.

Solar power does reduce carbon emissions, and is overall less harmful to the environment than traditional fossil fuels. One of solar power’s biggest environmental drawbacks, however, is its need for water in arid regions. Solar plants can use cooling systems that use less water, but they produce less electricity and pay higher capital costs when these systems are utilized. Another drawback of solar power is that the primary manufacturer of solar panels is China, where manufacturing companies have been known to harm residents and ecosystems through their disposal of toxic chemicals.

Germany has spent billions of dollars on solar, but the country's implementation of solar power has had many negative side effects, such as fiscal instability and high electricity prices, and practically no net environmental benefits.

If solar power truly is a viable alternative for more traditional energy sources, as solar energy advocates claim, it should be able to compete in the market without decades of government assistance. It is a mistake to view solar energy as an obvious alternative to conventional energy sources. Spending billions of taxpayer dollars on a system that is not predictable, efficient, or reliable is wasteful and illogical.

We conclude that solar-generated electricity is unreliable in two of the three aspects that we explored. The “green” face of solar is appealing to many, but the environmental benefits of solar energy are outweighed by its economic and physical costs.

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