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FEDERAL MANAGEMENT PROGRAM

Using Distributed Energy Resources A How-To Guide for Federal Facility Managers

Introduction combustion , , and systems. As one of today’s busy Federal facility or energy managers, you may be seeking ways to solve prob- How are DER systems used? lems such as high energy costs or low electric DER systems can be used in several ways. They can reliability at your facility. If so, distributed energy help you manage energy bills and ensure reliable Distributed resources (DER) could be the solution you’re power by augmenting your current energy services. looking for. Energy DER systems also enable a facility to operate inde- What are distributed energy resources? pendently of the grid, whether by Resources: choice or out of necessity. Certain DER systems can Distributed energy resources are small, modular, even lower emissions and improve utilization A How-To energy generation and storage technologies that on site. provide electric capacity or energy where you need Guide it. Typically producing less than 10 megawatts Utilities can use DER technologies to delay, reduce, (MW) of power, DER systems can usually be sized or even eliminate the need to obtain additional to meet your particular needs and installed on site. power generation, transmission, and distribution equipment and infrastructure. At the same time, DER systems may be either connected to the local DER systems can provide voltage support and electric power grid or isolated from the grid in enhance local reliability. stand-alone applications. DER technologies include wind turbines, How do I know if DER systems are the right Wind systems (PV), fuel cells, , choice for my facility? reciprocating engines, Today, several economic and environmental factors make it worthwhile to consider DER. These factors include the high prices associated with both electric Energy storage systems energy and fuel in recent years. Uncertain fuel sup- plies and the increasing potential for disruptions in service are prompting Federal man- agers to look for alternatives to traditional energy providers and for new ways to supplement current supplies. Solar systems Particularly where a facility’s energy-producing Microturbines infrastructure is aging, it may be time to review current operating costs and maintenance require- ments. The performance, cost, and availability of DER technologies have all been improving steadily over the past several years. New technologies are much more efficient than old ones, so a replacement or upgrade may pay for itself sooner Fuel cells than expected. Also, is a primary concern at many Federal facilities. In those cases, DER systems U.S. Department can power mission-critical loads, reduce of Energy hazardous or costly power outages, and Office of Energy diversify the local . DER systems are made up of many Efficiency and different power-generating Military facility energy managers, technologies. however, may want to consider the likelihood of privatization in deciding

Internet: www.eren.doe.gov/femp/ FEDERAL ENERGY MANAGEMENT PROGRAM

whether to invest in a DER system. If well as passive solar design and other the facility's utility infrastructure could effective techniques. (See FEMP’s Web STEP 1: soon be sold to a private entity, it might site, www.eren.doe.gov/femp/, for Analyze your not make economic sense to invest more information about energy-efficient energy needs in a new DER system that would be facilities.) The more you can reduce your unacceptable to a potential buyer. But in energy requirements, the smaller you the right circumstances, even military can size the DER system you will be facilities can benefit from using DER. installing. Here are seven steps you can STEP 2: follow to obtain a DER system that’s Select DER What is the purpose of this guide? right for you. technologies The Department of Energy’s (DOE’s) Federal Energy Management Program STEP 1: Analyze Your (FEMP) has established the Distributed Facility's Energy Needs Energy Resources Program to assist STEP 3: In this step, you can determine what Screen the Federal agencies in implementing DER your facility’s energy needs are, what technologies projects at their facilities. FEMP pre- problems you need to solve, and what pared this How-To Guide to assist facility benefits can be gained by using DER managers in evaluating potential appli- systems. This list of basic DER applica- cations and benefits. The guide also pro- tions will help you determine which one STEP 4: vides practical, step-by-step advice on or ones apply to your facility. It will also Acquire resources how to carry out a Federal DER project. help you choose appropriate DER tech- and assistance It describes and explains— nologies in Step Two. • DER applications, and the potential • Standby Power. Problem: Your power benefits of using DER in Federal supplier has an unacceptably high facilities STEP 5: incidence of service interruptions, or Develop a • DER technologies, and how to match takes a long time to restore service project plan them to applications after an interruption. This is called • A step-by-step approach to imple- low reliability, and the result is a shut- menting projects down in operations until power is restored. Solution: Install a DER sys- STEP 6: • Barriers that you may encounter, and tem that can meet your power needs Address potential how to overcome them when service is interrupted, to serve barriers • Resources that can assist you in critical loads until service is restored. implementing new DER projects. Benefits: Highly reliable operation, We hope this guide helps to make your minimal down time. STEP 7: DER projects a success. • Low-Cost Energy. Problem: Your Install and operate energy supplier has high rates. your DER system Seven Steps to Success Solution: Install a DER system to gen- How do you, as an energy or facility erate some or all of your facility’s power using renewable technologies, Following these seven steps will help you manager, determine whether DER will implement a successful DER project. make sense for your facility’s energy or change to more efficient and clean- er sources of generation. needs? And if so, which technology or needs electric energy, but it also has Benefit: Lower energy bills. system is the best? Finally, what is the other energy needs, for example, to process you need to follow to get a • Stand-Alone Systems. Problem: Your or cool or interior spaces. DER project financed, designed, facility needs electric energy, but it Solution: Install a DER system to installed, and operating? is in a location that can’t be served generate power and use the Before even considering DER, make economically by traditional utilities. heat for auxiliary processes that sure you have taken advantage of all Solution: Install a DER system to gen- would otherwise require fuel. the energy-saving measures that are erate power dedicated solely to off- Benefits: Substantially greater available and applicable to your facility. grid loads. Benefits: Independent efficiency, lower energy costs and fuel These include using highly efficient operation, cost savings. requirements, and fewer air emis- insulation, lighting, and heating, venti- • Combined Heat and Power (CHP, or sions, in many cases. (See p. 6, lation, and air-conditioning (HVAC), as Cogeneration). Problem: Your facility Table 2, for more information.)

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• Peak Shaving. Problem: Your power controls, communications, fuel supplier bills you a monthly charge handling and storage systems, based on your highest peak usage CHP systems, and emission con- rate, even if it’s only a few hours each trols. You will also want to weigh month. Solution: Install a DER to important environmental and provide power during times of peak fuel-use issues. usage to lower demand charges. Benefit: Lower monthly utility bills. What are the technologies? Photography/PIX05127 Jim Yost • Improved Power Quality (PQ). Many combinations of technolo- Problem: The power provided to your gies and fuel options are possible, facility by your energy supplier is to take advantage of the way indi- not electrically "clean" or constant, vidual technologies complement each other and to make them as causing problems with your facility’s Selecting a technology requires a thorough analysis of robust and cost-effective as possi- equipment (see page 8 for details). your facility’s energy needs. Solution: Install a DER system ble. See Table 2 for comparative cost and performance information designed to mitigate the particular lower emissions (and somewhat about today’s DER technologies, which power quality symptoms you are lower power output) than those of include the following: experiencing. For example, frequent a . In most other cost momentary outages can be effectively • Diesel Engine generator sets and operational respects, dual-fuel addressed with an uninterruptible (gensets) consist of a diesel-cycle engines are comparable to diesels; power supply (UPS) system or a dis- (compression ignition) reciprocating they are available in sizes from a tributed storage device. Benefits: engine prime mover coupled to an few kilowatts to about 10 MW at an Obtain cleaner power, ride through electric generator. The diesel engine installed cost of about $875/kW. momentary outages, protect delicate operates at a relatively high compres- • Natural gensets are made equipment. sion ratio and relatively low rpm. up of a reciprocating (piston-driven) Diesel engine gensets are a proven, • “Green” Power. Problem: Your facility -fueled engine using a cost-effective, extremely reliable and is in an environmentally sensitive spark-ignition system (Otto fuel widely used technology. They are area. Solution: Install low- or zero- cycle) coupled to an electric genera- manufactured in a wide range of emission DER systems that generate tor. In most other respects, natural sizes, from about 1 kilowatt (kW) up environmentally preferable power, gas engines perform similarly to to about 10 MW. They can be cycled such as wind turbines, photovoltaics, diesels and dual-fuel engines, but frequently to operate as peak-load fuel cells, or CHP systems. Replacing have the potential for the lowest power plants or as load-following old power generation equipment emissions of all types of reciprocating plants; they can also be run in base- with cleaner, more efficient DER tech- engines. They are available in sizes load mode in off-grid systems. Major nologies may also reduce emissions. from a few kilowatts to about 5 MW, drawbacks include very high levels of Benefits: Easier emissions permitting, and they cost about the same as diesel emissions (particularly nitrogen oxides, minimal environmental impacts. and dual-fuel engines—around a major component of smog), and the $825/kW. STEP 2: Select a DER need for sound attenuation to muffle the loud engine noise. Diesel engines • Combustion Turbines (also called Technology are thus probably not suitable for gas turbines) burn gas or liquid fuel; In this step, you can evaluate today’s most Federal facilities, and should be hot gases expand against the blades DER technologies, selecting the ones considered only if other technologies of a rotating shaft, producing a that meet your needs. Table 1 on pp. 4 are not practical. One of the least high-speed rotary motion that drives and 5 shows which technologies are expensive DER technologies, they an electric generator. While they may suitable for various DER applications. cost about $810/kW, installed. take a few more minutes to get up to Refer to the table as you weigh the pros speed in comparison to reciprocating • Dual-Fuel Engine gensets consist of and cons of the candidate technologies. engines, gas turbines are well suited a diesel-cycle engine modified to use for peaking and load-following appli- DER systems can be made up of one or a mixture of natural gas and diesel cations and for baseload operation in more primary technologies—such as fuel (typically, 5% to 10% diesel by larger sizes. Installed costs are some- internal combustion engines, combus- ) connected to an electric gen- what higher than those of reciprocat- tion turbines, fuel cells, photovoltaics, erator. The small amount of diesel ing engines, and maintenance costs wind turbines, and batteries—along fuel allows the use of compression are slightly lower. Turbines are effi- with supporting technologies—such ignition, and the high percentage of cient and relatively clean. They can as power conditioning equipment, natural gas in the mix results in much 3 FEDERAL ENERGY MANAGEMENT PROGRAM

Matching DER Technologies to Your Applications When using this chart to select a technology for a specific application, you will also want to consider such key factors as commercial readiness, economics, availability, and environmental considerations before making your selection. The discussion that follows should provide some additional guidance in selecting the technologies.

Table 1. DER Technology Applications Matrix

Technology Application Standby Low-cost Stand- Combined Peak Power Power Energy alone Heat & Shaving Quality System Power Diesel Engine ✓✓✓✓✓ Natural Gas Engine ✓✓✓✓✓ Dual Fuel Engine ✓✓✓✓✓ ✓✓✓✓ Combustion ✓✓✓✓✓ (1) ✓✓

Energy Generation Energy Photovoltaics (1) ✓✓ (1) ✓ Uninterruptible Power Supply (UPS) ✓✓ Battery System ✓✓ Flywheel ✓✓ Superconducting ✓ Storage (SMES)

Energy Storage Energy Hybrid Systems (2) ✓✓✓✓✓✓ (1) Although fuel cells, photovoltaics, and wind turbines may not offer the lowest cost power option, their low environmental impacts greatly enhance the value of the power they provide. (2) Hybrid systems are any combination of the technologies listed above.

Standby Power. To acquire the most economical DER combine generation and storage technologies for specific power-generating system to use when the utility supply is applications, have many benefits and may be best if you down, you should first estimate how often the DER will need fuel redundancy, expect a wide range in duration of have to start up and how many hours per year it will have outages, or have multiple applications. to operate. For standby power applications, fuel and Low-Cost Energy. If low-cost fuel is available, or electric maintenance costs will be low because outages usually rates are high in your area, or both, you may be able to occur only a few hours per year; consequently, capital reduce your utility bill by generating some or all of your costs should be low. Diesel engines are likely to be the own power. Diesel, dual-fuel, and natural gas engines least expensive option, but they can present environm are the least expensive to purchase, but emissions and ental challenges. Natural gas and dual-fuel engines maintenance costs should be considered when the num- may be more environmentally acceptable than diesels. ber of operating hours is high. Combustion turbines are Microturbines can be a good choice for small applications preferred for large applications; they have lower mainte- (less than 100 kW); combustion turbines can be good for nance costs and much lower emissions than reciprocat- larger applications, where natural gas is available and ing engines. Microturbines, which are relatively lower in emissions are a concern. UPS systems are well suited to efficiency and have higher capital costs, are probably not applications where outages last less than about 15 min- as cost-effective. Photovoltaics, although high in cost ini- utes. Batteries can handle applications of a few kW for tially, often make sense in the long term, especially if the outages of about 1 to 2 hours. Hybrid technologies, which

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local utility has established rules (see below technology that can produce can be used in a for more information). Wind turbines are less expensive CHP application with greater overall system efficiencies than PV arrays, but may not qualify for net metering. (because of the higher fuel utilization efficiency) and per- However, in areas with high average wind speeds, haps better economics. (See page 9 for more informa- turbines can provide a substantial amount of energy. tion. You can also use the CHP Online Calculator—see Hybrid systems—such as PV or wind with batteries—are Resources on p. 16 —to determine whether CHP is cost- more expensive but over a broader range of fuel effective for your needs.) costs and applications than single technologies. In addi- Peak Shaving. DER systems can generate power during tion, using the waste heat generated by some DER the times when purchasing energy from the utility would technologies to produce both heat and power on site be very expensive. These include hours, can reduce overall energy costs. when time-of-use rates are in effect, and hours when utili- Stand-Alone Systems. A DER in this application will ties are capacity-constrained. Utilities often assess run around the clock and constantly match its output to demand charges—monthly charges based on highest the demand. Therefore, high efficiency is required to peak usage—for commercial customers. Using DER to minimize fuel costs and emissions. Maintenance costs limit peak usage will help you avoid these costs. The sys- are also an important factor, and reliability is paramount. tem may run 200 to 2000 hours per year, so you should Engines and combustion turbines are often the first consider the trade-off between installation costs and effi- choices in terms of capital cost. Engines and microtur- ciency to select an appropriate DER technology. Engines bines are usually preferable for smaller applications; and hybrids are likely to be preferable for small applica- combustion turbines are preferable for larger applica- tions at lower run times, and turbines for larger applica- tions. Fuel cells are the most expensive to install but tions at higher run times. PV systems can provide peak desirable from an environmental perspective. PV, wind shaving in facilities where the greatest requirement for turbines, and hybrid systems are beneficial in areas with- energy occurs when the solar resource is at its highest out adequate supplies of fossil or where environ- intensity, such as for air-conditioning in commercial build- mental permitting is difficult, and in off-grid applications ings. For these applications, PV systems have excellent where grid extensions are very expensive. Particularly load-matching characteristics. in remote, off-grid areas, the cost of operating and main- Power Quality. Any DER prime mover technology can be taining fossil-fuel-fired engine gensets is significant. The used to provide dedicated, high-quality power to highly cost of transporting and storing fuel, combined with the sensitive or mission-critical loads and to eliminate down- potential for fuel spills and subsequent cleanup, can time. For small applications and brief power outages, a make hybrid renewable energy systems much more UPS is likely to be the most economical choice. For volt- life-cycle cost-effective than fossil gensets alone. age sags, spikes, noise, and other random PQ anom- Combined Heat and Power (CHP). Only the power- alies, preferred technologies include batteries, flywheels, generation technologies that produce excess heat can be and SMES. They can be operated in a constantly-on used for CHP applications; these include engines, com- mode, filtering out unwanted qualities of the power signal. bustion turbines, fuel cells, and microturbines. Additional Adding higher quality electronics and energy storage sys- equipment must be installed to capture the heat and use tems can improve the power quality of any prime mover it in the secondary process, at an average additional cost technology. See page 8 for more information about power of $400/kW. Engines and turbines (including some micro- quality. turbines) have been used for CHP applications. Any DER

Net Metering Net metering measures the difference between the electricity you buy from your utility and the electricity you produce using your own generating equipment. Your electric meter keeps track of this "net" difference as you generate electricity and take electricity from the grid. Your utility or electric service provider bills you for the “net” energy you use (if any) on a monthly or yearly basis, depending on the program. Net metering allows you to get full retail value for most, if not all, of the electricity you produce. Any excess electricity you generate goes back into the electric grid and essentially credits future energy use. Getting this high retail value for your excess electricity makes owning your own generating system more cost-effective. Net metering programs have been enacted in 35 states. Although specific requirements vary signif- icantly from state to state, many programs allow net metering for residential and commercial customers, with system size limits of 10Ð100 kW. Check with your state’s public utility commission for the specific rules that could apply to you. For a summary of state net metering programs, see www.eren.doe.gov/greenpower/netmetering.

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Table 2. Summary of Cost and Performance Parameters for Technologies

Technology Size Range Installed Cost Heat Rate Approx. Variable Emissions (1) (kW) ($/kW) (Btu/kWhe) Efficiency O&M (lb/kWh) (2) (%) ($/kWh) NOx CO2 Diesel Engine 1Ð10,000 350Ð800 7,800 45 0.025 0.017 1.7 Natural Gas Engine 1Ð5,000 450Ð1,100 9,700 35 0.025 0.0059 0.97 Natural Gas Engine w/CHP (3) 1Ð5,000 575Ð1,225 9,700 35 0.027 0.0059 0.97 Dual-Fuel Engine 1Ð10,000 625Ð1,000 9,200 37 0.023 0.01 1.2 Microturbine 15Ð60 950Ð1,700 12,200 28 0.014 0.00049 1.19 Microturbine w/CHP (3) 15Ð60 1,100Ð1,850 12,200 28 0.014 0.00049 1.19 Combustion Turbine 300Ð10,000 550Ð1,700 11,000 31 0.024 0.0012 1.15 Combustion Turbine w/CHP (3) 300Ð10,000 700Ð2,100 11,000 31 0.024 0.0012 1.15 Fuel Cell 100Ð250 5,500+ 6,850 50 0.01Ð0.05 0.000015 0.85 Photovoltaics 0.01Ð8 8,000Ð13,000 -- N/A 0.002 0.0 0.0 Wind Turbine 0.2Ð5,000 1,000Ð3,000 -- N/A 0.010 0.0 0.0 Battery 1Ð1,000 1,100Ð1,300 -- 70 0.010 (4) (4) Flywheel 2Ð1,600 400 -- 70 0.004 (4) (4) SMES 750Ð5,000 600 -- 70 0.020 (4) (4) Hybrid Systems 1Ð10,000 (6) (5) (5) (5) (5) (5)

(1) Nationwide utility averages for emissions from generating plants are 0.0035 lb/kWh of NOx and 1.32 lb/kWh of CO2. (2) The high end of the range indicates costs with NOx controls for the most severe emissions limits (internal combustion technologies only). (3) Although the electric conversion efficiency of the prime mover does not change, CHP significantly improves the fuel utilization efficiency of a DER system. (4) Storage devices have virtually no emissions at the point of use. However, the emissions associated with the production of the stored energy will be those from the generation source. (5) Same as generation technology selected. (6) Add cost of component technologies.

easily be fitted with pollution con- install. The newest versions meet trols to run even cleaner. They are very low emissions requirements. available in sizes ranging from Microturbines are commercially about 300 kW to several hundred available and currently cost around megawatts, and costs range from $1,000/kW. $910/kW to $1,400/kW, installed. • Fuel Cells produce DC electricity by • Microturbines are smaller, somewhat a thermochemical process in which less efficient versions of combustion (H2) is passed over an

turbines, in the range of about 30 to anode and air over a cathode in an Corporation/PIX08130 Capstone Turbine 250 kW. They run on natural gas at electrolyte bath; the DC power is high speeds (typically around inverted to AC for grid operation. By- 90,000 rpm). The electrical output of products are heat, water, and carbon the generator is typically passed dioxide, making fuel cells one of the through an inverter (an electronics- cleanest sources of energy. Unless it is Microturbines can be powered by natural gas based power converter, also called a transported to the site, the hydrogen or to provide a reliable source of power conditioning unit or PCU) to comes from reforming a fuel such as power. provide 60 Hz AC power. Micro- natural gas or propane, a process that turbines targeted to the small indus- may produce environmental emis- oxide, molten carbonate, and proton trial and commercial market are sions. Fuel cells using a phosphoric exchange membrane (PEM) technolo- designed to be compact, affordable, acid electrolyte were the first to gies are poised to follow. Fuel cells reliable, modular and simple to become commercially available; solid are efficient, quiet, and modular.

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They are available in sizes ranging • Hybrid Systems are combinations from a few to 200 kW—the cur- of these technologies, designed for rent commercially available size for specific or unusual applications. stationary power applications. Renewable energy technologies such Although costs are expected to go as wind and solar systems, for exam- down, fuel cells are now one of the ple, depend on energy sources that most expensive DER technologies, cannot be dispatched—i.e., we have starting at about $5,500/kW, Inc./PIX04779 Atlantiws Energy, no control over their availability. installed. FEMP’s Federal Technology For this reason, it can be necessary Alert on fuel cells (see Resources, to combine them in a hybrid system, p. 16) provides more information. such as a PV system with battery • Photovoltaic Cells are thin layers of backup, to collect energy for use a semiconductor (usually crystalline when a facility needs it. Nonrenew- A over the entryway to silicon) that convert sunlight directly able hybrid DER systems are also this building in San Francisco generates to DC electricity; an inverter converts used; one example is a battery system power on site. the DC to standard AC power for packaged with a microturbine, to ride connection to utility systems. These through short outages with the bat- proven technology and are available teries and use backup power from the “solar cells” are built up into panels from several manufacturers. with power ratings ranging from a microturbine for sustained outages. few watts to about 100 W. The panels • Storage Devices take energy from the Depending on your needs, more than are modular and can be configured electric grid or another source (such one of these technologies and systems into larger arrays to match almost as a renewable DER) and store it, might work for you. In that case, any load requirement. Noise and making it available when needed. you could custom-design several emissions are nonexistent, and main- Storage technologies currently avail- technologies and control systems to tenance is minimal because there are able have a range of characteristics obtain the greatest benefit. no moving parts. Photovoltaic sys- for various applications. Batteries are tems are a proven technology and the most common form of electric What are the environmental issues? are available from numerous manu- energy storage; applications range An important consideration in choosing facturers. Depending on the applica- from low-power uses, such as remote a DER technology is the environmental tion, PV systems can range from telecommunications, to high-power impact associated with it. Certain DER $8,000/kW to $13,000/kW, installed. uses, such as utility grid support systems can have a positive impact on (requiring an inverter). A UPS is Grid-connected systems typically fall air emissions, particularly NOx and SOx, in the low end of the range, while sys- another common storage system, typ- which are by-products of fossil fuel com- tems with battery storage constitute ically consisting of batteries mated to bustion and key constituents of smog. the high end. control electronics that convert stored Table 2 shows output levels of the key energy to AC electricity and dispatch Wind Turbines • , another renewable it as needed (for example, to provide , contain propeller- full power during an outage or to like blades that turn the energy in the smooth out power quality problems). wind into rotational motion to drive Flywheels convert electric or mechani- a generator. Most wind turbines are cal energy into and asynchronous, meaning they turn at invert it for use when needed. variable speeds; the output of the Superconducting magnetic energy arren Gretz, NREL/PIX01497 W generator must pass through an storage (SMES) uses a magnetic coil inverter to achieve 60 Hz AC electrici- cooled to very low temperatures to ty. Wind turbines range in electrical store electric energy with little loss; output from a few watts to more than like other DC devices, it uses an 1 MW. Applications include remote inverter to convert DC to AC that power systems, small-scale or resi- can be dispatched to a utility grid. dential electricity production, and These storage technologies are all utility-scale power generation. DER- commercially available and becoming scale systems can cost anywhere from more cost-effective as applications $1,000/kW to $3,000/kW installed, increase. The cost of purchasing and depending on the application. Like installing energy storage systems can Wind turbines can be purchased in either small or large sizes, depending on a facility’s photovoltaics, wind turbines are a range from $1,100/kW to $1,300/kW. needs.

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Power Quality The power generated by an electric utility starts out Figure 1: Normal Power Waveform as a “clean” 60 Hz sine wave (Fig. 1), but both utility +V and customer equipment can affect the pureness (quality) of the power delivered to the user. Load and generation changes, equipment switching, and 0 electronically controlled loads can all cause signifi- cant disturbances to the electrical waveform. Poor power quality can be merely annoying or it can -V adversely affect or damage sensitive loads such as computers, adjustable-speed drives, and motors, disrupting important facility processes. Figure 2. Voltage Sags and Swells Symptoms of poor PQ include the following: +V Voltage sags and swells — the voltage is too high or too low for a period of several cycles to several min- 0 utes (Fig.2). Voltage spikes — sharp, randomly occurring pulses in the voltage (Fig. 3). -V Momentary outage — complete interruption of power for up to 5 minutes (Fig. 4). Figure 3. Voltage Spikes Harmonic distortion — variation from a pure sine wave due to harmonic frequencies (Fig. 5). +V Other signs of poor PQ are variations in the frequen- cy from a constant 60 Hz, noise (low-level random 0 voltage variations), and unbalanced voltages and currents between the three phases of the electric -V system. How do you know if you've got PQ problems? You may see lights flicker or go dim or bright. Motors can vibrate, make noise, overheat, or stall. Outages are Figure 4. Momentary Outage easy: everything goes black. Some symptoms are +V hard to detect, so you might want to ask your local utility or a consultant to monitor your power and do a PQ analysis for you. 0 If your facility has experienced any of these symp- toms, first ask your local utility or vendors about the -V solutions they could provide. In many cases, improper grounding or problems inside your facility may be to blame; sometimes nearby customers are the source of the problem. Because many utilities Figure 5. Harmonic Distortion make no warranties concerning power quality, you +V may need to consider installing PQ mitigation tech- nologies. These include UPS, battery systems, stor- age technologies, motor-generator sets, isolation 0 , voltage regulators, line conditioners, filters, shielding and grounding techniques, and -V surge suppressors.

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regulated emissions of DER technolo- Combined Heat and Power gies, CO2 and NOx; SOx emissions are Many types of distributed generation can provide useful and valuable thermal negligible for most DER technologies, energy by capturing excess heat energy produced during electricity genera- since the fuel used is typically natural tion and using it to heat or cool water or interior space. The excess heat can gas. Note that the units employed are also be used as energy input to an industrial process, in lieu of burning fuel. pounds per kilowatt-hour (lb/kWh); This energy capture and process is known as combined heat and this is an example of an output-based power, CHP, or cogeneration. standard, which relates emissions levels to the efficiency of the technology, and Some energy users require substantial amounts of heat, especially for indus- allows technologies to be compared on trial, institutional and agricultural operations. In those cases, CHP can save a consistent basis. Sometimes emissions enough on fuel costs to substantially improve the overall economics of DER measurements are given in terms of installations. input (e.g., pounds of pollutant per mil- Federal facilities that are likely to benefit the most from CHP applications lion Btu of fuel input) or on the basis include hospitals, prisons, R&D facilities, and industrial buildings. of concentration (parts per million, or ppm). These measures do not clearly Assuming that the combustion of fuel to produce heat (usually in a ) is link actual emissions to the amount of typically up to 85% efficient, each Btu of heat captured from the distributed product (in this case, kWh of energy), generator in a CHP process offsets the need to burn about 1.18 Btu of fuel. making it difficult to determine which The incremental project cost for CHP is highly site-specific, but generally technologies are the cleanest. about $400/kW. This represents the estimated costs for piping, heat exchang- ers, and engineering associated with installing CHP. CHP system integration Table 2 lists the heat rates of the tech- can sometimes be simplified at facilities that already have a central plant or nologies in terms of Btu/kWh, repre- a large mechanical room, thereby reducing costs. And any site with a senting the amount of fuel input plant that runs at moderate to high pressures might be able to use back- required per kilowatt-hour of electrical pressure steam turbines to generate electricity cost-effectively. output produced. This can help you evaluate the fuel requirements of a DER CHP can also have substantial environmental benefits by reducing air emis- for a given output and hours of opera- sions from or other processes that require heat input. This fact may tion, as well as output-based emissions be helpful in obtaining permits from local air regulatory authorities. Nominal in lb/kWh, so you can choose the values for avoidable boiler emissions are shown in the table below. They are cleanest feasible technology for your based on the leading data source for this kind of information, the U.S. facility. Note that renewable energy sys- Environmental Protection Agency. In addition to nitrogen oxides and carbon tems and fuel cells have virtually no air dioxide (NO and CO ), boiler emissions can also include sulfur oxides X 2 emissions. Because overall system effi- (SO ), carbon monoxide (CO), volatile organic compounds (VOCs) and par- X ciencies are higher, CHP systems also ticulate matter (PM). (Values shown in Table 3 are representative of boilers have lower emissions than DER systems currently in use that are the most likely candidates for replacement by CHP, that do not utilize waste heat. so they are somewhat higher than values for newer, more efficient boilers.) Table 3. Avoided Boiler Air Emissions for CHP Operation Keep in mind that any energy your facil- (pounds per million Btu) ity generates usually displaces energy previously generated by some other source, so net emissions are a key con- NOX SOX CO CO2 VOC PM sideration. For example, if you install a Nominal 0.14706 0.00059 0.0824 118 0.00539 0.00745 wind turbine, all the air emissions from Best Reported 0.03137 0.0235 the usual generation source (e.g., the local utility), will be avoided for each Poorest Reported 0.2745 0.0961 kWh of energy the wind turbine pro- duces. On the other hand, if you install a FEMP offers free CHP screenings; please contact your DOE Regional diesel engine, then it is possible that net Office representative for more information (see Resources on p. 16). And see emissions will be greater, because Oak Ridge National Laboratory’s online CHP evaluator: www.eren.doe.gov/ diesels have higher levels of some key der/chp/chp-eval.html. emissions on a per-unit basis than most conventional utility generation methods. Table 2 shows the average emissions for U.S. utility generation, which is a mix of fossil fuel (, , and natural gas),

9 FEDERAL ENERGY MANAGEMENT PROGRAM

Natural gas is a cleaner alternative to “showstoppers” to derail your project, Electrical Output: diesel, and it is comparable in terms of and that the economics of your choices AC vs. DC overall cost. In areas where gas utilities are favorable. have pipelines, a gas line extension may Virtually all electric systems in For example, if natural gas is not avail- be required, at additional cost, but a common use in North America able at your facility, a technology that storage tank is not needed. If it is today are 60 Hz alternating current requires it is clearly not the right choice. impractical or prohibitively expensive (AC) systems. Some DER tech- If air emissions are strictly controlled in to run a gas line, you may need gas nologies—like engines and com- your area, diesel engines would not be delivery and a storage tank. Propane is bustion turbines—produce AC acceptable, either, and other fossil fuel another alternative to diesel fuel, where power directly and can be connect- technologies may be problematic, as natural gas is not available. Natural gas ed to the electric grid or AC loads well. Be sure your choices do not stop and propane may or may not be cleaner in a straightforward manner. Other the show in terms of making your alternatives to ; it depends on technologies—like fuel cells, pho- project a success. the application. tovoltaics, and wind turbines—pro- You can also look at the barriers in Step 6 —plant matter such as trees, duce direct current (DC) power, to see if any of them would categorically grasses, agricultural crops or other bio- which must be passed through a rule out any of the DER options you logical material—can also be used in power electronics device, called an have selected. Then, you’ll want to place of some fossil fuels. The most com- inverter or power-conditioning unit, conduct an economic evaluation. to produce 60 Hz output that can mon forms of biomass used to generate then be connected to AC systems. electricity are the residues from the food, Some people balk at the high first costs fiber, and forest product industries. But of certain DER technologies, such as fuel facilities and cells and PV systems. Researchers are , nuclear, geothermal, and sewage treatment plants can also pro- still working on ways to reduce these a few other sources. duce fuel to power DER technologies. initial costs to more competitive levels. Noise will also be a consideration in However, many DER technologies are PV systems depend on the availability choosing a DER technology, because of life-cycle cost-effective in certain appli- of sufficient sunlight in a given area. By the proximity of the system to homes cations right now. paying careful attention to the design and businesses. Most urban and subur- and placement of the solar panels, and Federal facilities are required to perform ban areas have noise ordinances, so adding energy storage batteries (typical- life-cycle cost assessments on all plan- mufflers or other sound attenuation ly, the deep discharge type), you can ned energy projects, because these assess- methods may be necessary. In addition, maximize the potential of your solar ments take into account the benefits of a visual and aesthetic impacts are some- installation. project over its entire operational life. times a concern, requiring landscaping, For example, a PV system has a higher Wind energy is also highly dependent enclosures, or other measures. capital cost than a similarly sized natu- on location, especially on the average ral gas engine. But the PV system does What fuels should be used? wind speed in a given locale and the not use fuel and can last up to 20 years daily and seasonal variations in wind Availability, price, and storage are the or more. The natural gas engine, in con- speed. Again, adding storage can pay key concerns regarding the fuel used trast, will use a lot of fuel during its life- off in terms of the overall functionality to power your DER system. time, which may only be a few years. of a wind system. Diesel fuel is readily available at a You can evaluate the cost-effectiveness Hybrid systems, such as wind or PV reasonable cost; however, it requires of a DER system by comparing the life- plus storage and a small diesel backup an on-site storage tank and periodic cycle costs of your current energy usage generator, may be necessary and cost- deliveries, and spills or fumes are scenario to the scenario in which a effective in situations where high relia- always possible. DER system is designed, installed, bility and/or stand-alone operations and operated. Biodiesel fuel can be an alternative for are required. diesel engine generator sets in areas To simplify this process, DOE provides where it’s available. Biodiesel is made STEP 3: Screen the a Building Life Cycle Cost (BLCC) by reacting natural and fats with an Technologies economic analysis software tool, which alcohol. It is generally distributed as a is used to analyze the life-cycle cost- 20% blend with number 1 or 2 diesel At this point, it is a good idea to perform effectiveness of energy technologies fuel. Biodiesel can significantly reduce a screening exercise to eliminate DER (including DER) in an integrated facility CO2, SO2, and particulate matter emis- candidates that are not really practical environment. See Resources on p. 16 for sions, but it may increase NOx in some or feasible for your facility. This helps more information on BLCC and how to cases. you make sure that there are no use it.

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STEP 4: Acquire Resources alternative financing assistance, education, Line up resources you can call on for and outreach. See the assistance—the earlier, the better. These FEMP Web site and can include— check with your • Process experts. Contact your DOE DOE Regional Office

Regional Office (see FEMP’s Web site representative (see arren Gretz, NREL/PIX06445 W for a list of contacts). Your Regional Resources on p. 16) Office representative can walk you for more information. through the process and help you work with regulatory agencies, utili- STEP 5: Develop ties, energy service providers (ESPs), a Project Plan energy service companies (ESCOs), national laboratories, and independ- At this point, you should ent consultants in your area. have a specific technolo- gy approach in mind, • Technical experts. Programs at DOE, designed to meet your FEMP, and the national laboratories facility’s energy needs. are staffed by many technical experts One of the first things DOE FEMP can help your agency obtain innovative financing for DER projects. in DER. Your DOE Regional Office you will need to do is representative can help you identify evaluate the feasibility the people to contact for assistance. of your DER concept. permits are not required for PV systems.) You might also want to contact local These tasks should be done concurrently, utilities, your state’s energy office, • Feasibility. First, conduct a prelimi- since they are largely independent of ESPs, ESCOs, consultants, manufactur- nary screening of your concept to each other. Note, however, that permits ers, and equipment vendors yourself. evaluate its cost-effectiveness. This and utility connections can be costly; this step takes little time, requires minimal could change the economic viability of • Financial support. In addition to data, and will help you decide a project that looked promising in the direct appropriations, there are two whether to proceed with a more feasibility study. approaches that Federal agencies detailed study. You can request assis- Financing can take to share the financial risk tance with this screening from your • . Explore financing options, of a project. They are utility energy DOE Regional Office (see Resources, using the resources described in services contracting (UESC) and p. 16) or from local vendors and con- Step 4, where possible. Contact your FEMP’s energy savings performance tractors that specialize in the technol- State Energy Office, DOE Regional contracting (ESPC and Super ESPC) ogy and application you selected. If Office representative, or local utility programs. These contracts allow the preliminary screening indicates to see if any incentive programs are Federal agencies to leverage private- that the project will be cost-effective, available to help with the cost of your sector financing to install energy you can move forward with a full- DER system. improvements when appropriated scale feasibility study. Again, your • Air Permits. Apply for air permits funds are not available. The utility or DOE Regional Office or local vendors from the local air resources control ESCO is repaid for capital costs from and contractors can assist you. You board, as needed. Depending on the the savings in the agency’s utility bill. will need to reevaluate the cost- size, type, and potential impacts of Participating local utilities and ESCOs effectiveness of the project every time your project, this can take up to six can contract for installation. Look for you add new costs and benefits. If months for technologies having emis- local utility rebates, tax credits, state the results of the feasibility study are sions. Fees will be assessed to evalu- or Federal incentive programs, and positive, you can then prepare a more ate the project, and will probably be opportunities to partner with private- detailed project design. This design proportional to the expected total sector financers, developers, and determines the specifications stated yearly emissions. See Step 6 for addi- manufacturers as well; check the in your request for proposals (RFP). tional information on air permits. FEMP Web site for more information about SER funding opportunities. If the results of your feasibility study • Utility Connections and Rates. are positive, you can start developing a Apply for interconnections with local • FEMP DER Program. FEMP offers a plan to have your DER system financed, utilities. This includes electric inter- variety of services to Federal agencies built, and installed. You will also need connections for all DER projects that are considering DER projects, to complete the tasks below that apply to connected to the utility, and gas including technical assistance, your project. (For example, air emissions line interconnections for projects

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requiring gas at higher volumes and mulate plans and strategies pressures than the gas distribution to overcome or avoid them. system can provide. Typically, you will file an application with the utili- Overcoming technical ty, providing basic information about barriers the proposed project and enclosing a These barriers relate prima- nominal payment for processing rily to your local utility's and review. You will be informed electrical interconnection after a specified period (typically, requirements, which are two to three weeks) whether a more meant to ensure that your involved study is required, what it DER will not negatively will include, what it will cost, and impact the reliability, safety, Sacramento Municipal Utility District (SMUD)PIX01026 approximately how long it will take and power quality of the (typically, about six weeks). This electric grid system. Other study will then describe the utility technical barriers can system upgrades (if any) that are nec- include fuel availability or essary, what they will cost, and when storage; space limitations; they can be scheduled. It is then up to power quality impacts; fire, PV systems generate no emissions and are exempt from air you to evaluate the cost in relation to safety, and zoning require- permitting requirements. your project’s total cost and projected ments; and operations and savings, and decide if your project is maintenance issues. Projects (see Resources on p. 16), still cost-effective. See Step 6 for more found that this was a consistent You can begin by finding a contact per- information. factor among projects that reported son at the utility and asking for intercon- timely progress in obtaining Utility rate impacts should also be nection guidelines. Although the utility interconnections. investigated carefully. A new DER might not have established formal system can change your facility’s guidelines or rules, someone there • Ask the utility contact for proper energy demand and thus your rate should be responsible for handling application forms, and make sure you structure. Large, gas-fired DER sys- interconnection requests. understand the technical data they tems have high, consistent fuel are requesting. You or the contractor Some utilities have expedited or simpli- demands, though you might be able will have to provide these data when fied rules for certain types of DER. For to negotiate a lower fuel rate. applying, and you may need to con- example, renewable energy systems pro- Interruptible electric rates may pro- tact equipment vendors or other ducing less than 10 kW may require vide cost savings if the DER system resources to obtain the data. provides backup power. It is a good nothing more than an inspection by the • Ask the utility to specify how long it idea to look into anything that can utility. Larger DER installations may will take to process the application, save money and improve the eco- require an engineering review, or even a and what fees must be submitted nomics of your DER system. full-fledged study. A study can take a utility from two to six weeks to perform, with it. STEP 6: Address Potential and you will probably be required to • Utility commissions in some states Barriers pay the utility's costs to conduct it. The have established regulations specify- result may be that protective equipment ing the interconnection process. Find As your project nears completion, you or other hardware must be installed, and a contact person at your state's utility will need to work with various entities you will be required to pay for that as well. commission and ask for any guide- to obtain permits, connect to the utility How can you tell if the utility's demands lines or rules that apply. Also, ask system, and perform other activities are appropriate for your specific whom to contact for dispute resolu- external to your facility. Some of these installation? And how do you make sure tion, if that becomes necessary. activities will require more time, effort, that the process is handled with a mini- • Requirements for smaller DER sys- and money than you originally estimat- mum of delays? Here are some tips: tems should be easier, especially ed and may pose certain barriers you those for renewable energy systems. will have to overcome. This section • Find someone to be your point of con- For installations under 10 kW, will help you identify potential project tact at the utility and maintain this requirements are often minimal to barriers; estimate their impacts on your throughout the process. A recent none, particularly for renewable project in terms of additional time, study, Making Connections: Case energy systems. For systems up to money, and expertise required; and for- Studies of Interconnection Barriers and their Impact on Distributed Power 100 kW, a study is likely to be

12 FEDERAL ENERGY MANAGEMENT PROGRAM

required, but it should not take more requirements and procedures for imple- For most states, air permit requirements than a few hours for the utility engi- menting DER projects. and the required forms are available on neer to determine impacts, and inter- the Internet. connection requirements should not Overcoming regulatory barriers Note that even if the DER displaces an be great. Above 100 kW, the impacts Moving to the operational stage in a older, less efficient or more-polluting on the utility system can be signifi- DER project means obtaining numerous source, it may be treated as a “new cant, so more study is likely to be permits and approvals. These can be source” and be subject to much more needed, and interconnection costs economic as well as regulatory barriers, stringent emissions requirements. are likely to be higher. because time, effort, and money go into Some states make an allowance for the • If the DER will be used for on-site overcoming them. Since many permits emissions reduced by using CHP (see power requirements only, and no require fixed fees regardless of the size page 9), which could make permitting power will be exported or sold back of the DER project, the impacts on small- requirements less stringent. However, to the utility, the interconnection er projects can be greater than those for most states do not make such an requirements may be different from large projects. The Making Connections allowance, so be sure to ask the air regu- those for an exporting condition. For study documented numerous cases in latory agency whether CHP allowances safety, utilities will require that the which the economics of small projects are given in your state. DER have protection equipment that were seriously impacted by the costs of Land use or conditional use permits will disconnect it if the utility system meeting regulatory permitting, where may be required by the local city or shuts down. such costs were a smaller percentage of larger projects. county government, and will depend on • If the utility has an interconnection zoning regulations governing the site. handbook, as many do, it will specify Other barriers arise because of utility Find a contact at the local planning the process and requirements, both regulations. Standby charges are department and ask your contact what for the utility and for the DER appli- assessed because the utility is obligated permits are required, what the requisite cant. It should also specify time limits to serve your load if the DER is not fees are, and what the application process for various steps in the process, and available, and the utility must maintain and schedule are. A public hearing might what costs must be borne by the adequate distribution facilities. Exit fees be required, which is also an excellent applicant. repay the utility for distribution facilities opportunity to make a positive presenta- already built that are "stranded" because tion on your project to win local support. • Some utilities have expedited rules your DER reduces the utility's return on for "certified" DER equipment, i.e., investment. Similarly, regional transmis- It is often possible to require a contractor systems that have been tested and sion charges may be assessed for strand- to obtain all the studies, permits, inter- approved for use on the utility's ed transmission assets. Ask the utility connection agreements, and other require- distribution system. what charges apply in your case. ments as part of a turn-key design/ • The Institute of Electrical and build/operate contract. You can explore Environmental permitting (primarily, Electronics Engineers (IEEE) is options for such a contract when consid- obtaining an emissions permit) is developing a standard, labeled P1547, ering financing alternatives. Ask poten- probably the single most arduous and for interconnection of DER facilities; tial DER developers what options are costly task in getting a DER online. although it had not yet been available and appropriate for your site. Contact your state or local air quality approved by the date of this publica- management agency in charge of tion, many states are adopting similar STEP 7: Install and Operate enforcing air regulations. Ask them rules. If your facility meets this pro- the following: Your DER! posed standard, this should expedite Now you are ready to build and operate the process. • What are the air emission regulations your new DER system. Congratulations! in my area? • If possible, find out what other facili- You are adding an important new ener- ties in your utility’s service area have • How do I apply for an emissions gy source to your facility that will bring done or are considering in terms of permit? many benefits to your operations and DER projects. Other facility managers • What data do I need to supply? improve your bottom line. may be able to offer you valuable • What are the fees for the permit? advice based on their own experiences. Typically, fees are proportional to If your DER project involves the use of the expected amount of annual natural gas or propane, don’t forget to pollutants. Renewable systems and contact your local gas utility if it is not fuel cells should require minimal the same as your electric utility. Your gas permitting, because they have utility may have additional or different virtually no emissions.

13 FEDERAL ENERGY MANAGEMENT PROGRAM

DER Process Flowchart

Analyze your facility's energy needs and infrastructure.

Did you install all cost-effective No Energy Implement measures? audit conservation measures. Yes

Select candidate DER technologies.

Screen technologies for showstoppers. No Are technologies still feasible?

Yes

Perform economic No analysis of STOP technologies. Are they cost-effective?

Yes

Acquire project resources and technical assistance.

Solicit and Select financing Apply for air, Apply for and acquire evaluate method. land use, etc., electric and gas contractor bids. permits. interconnections.

Install and operate your DER.

14 FEDERAL ENERGY MANAGEMENT PROGRAM

Glossary of Terms AC — alternating current Btu — British thermal unit(s) CHP — combined heat & power CO — carbon monoxide

CO2 — DC — direct current DER — distributed energy resources ESCO — energy service company ESP — electric service provider ESPC — Energy Savings Performance Contract IEEE —Institute of Electrical and Electronics Engineers interconnection — the physical connection of distributed energy resources to the utility system in accordance with prevailing regulations and standards, so that parallel operation can occur inverter — a machine, device, or system that changes DC power to AC power (see IEEE Standard 100) kV — kilovolt(s), an amount of voltage equal to one thousand volts kW — kilowatt(s), an amount of power equal to one thousand watts kWh — kilowatt-hour(s) MW — megawatt(s), an amount of power equal to one million watts

NOX — oxides of nitrogen O&M — operation and maintenance PCU — power-conditioning unit; an inverter PM — particulate matter PQ — power quality PV — photovoltaic(s)

SOX — oxides of sulfur UESC — Utility Energy Services Contract VOC — volatile organic compounds volt — unit of electric potential — unit of power

15 FEDERAL ENERGY MANAGEMENT PROGRAM

Resources For More Information FEMP Help Desk Federal Building Life-Cycle Cost (BLCC) Software Tool for (800) 363-3732 Download International callers please Department of Energy — Federal Energy www.eren.doe.gov/femp/techassist/ use (703) 287-8391 Management Program (FEMP) softwaretools/softwaretools.html Web site: www.eren.doe. www.eren.doe.gov/femp gov/femp Department of Energy — Distributed General Contact Resources Program Edison Electric Institute Shawn Herrera www.eren.doe.gov/der www.eei.org Program Manager Federal Energy Department of Energy — Regional Office FEMP Energy-efficient Product Information Management Program Representatives www.energystar.gov U.S. Department of Energy www.eren.doe.gov/femp/aboutfemp/ 1000 Independence Ave., SW fempcontacts.html.#regional Engine and Turbine Manufacturers Directory Washington, D.C. 20585 www.dieselpub.com/catalog/ Phone: (202) 586-1521 Department of Energy — Office of Power Fax: (202) 586-3000 Technologies Fuel Cell Council [email protected] www.usfcc.com www.eren.doe.gov/power Laboratory Contacts Online Fuel Cell Information Center FEMP Design Assistance Program Distributed Energy www.fuelcells.org www.eren.doe.gov/femp/techassist/ Resources: designassist.html Fuel Cell Developers Trina Brown http://216.51.18.233/fcdevel.html National Renewable FEMP New Technology Demonstration Program Energy Laboratory (NTDP) Industries Association 1617 Cole Blvd. www.eren.doe.gov/femp/prodtech/ www.seia.org Golden, CO 80401 newtechdemo.html Phone: (303) 384-7518 Database of State Incentives for Renewable Energy Fax: (303) 384-7411 FEMP Federal Technology Alerts www.dsireusa.org [email protected] www.eren.doe.gov/femp/prodtech/ American Wind Energy Association Combined Heat and fed_techalert.html Power: www.awea.org Patrick Hughes FEMP Renewable Energy Resources Electricity Storage Association Oak Ridge National www.eren.doe.gov/femp/techassist/ www.energystorage.org/ Laboratory renewenergy.html P.O. Box 2008, Bldg. 3147 Distributed Power Coalition of America Oak Ridge, TN 37831- FEMP SAVEnergy Program www.distributedpower.com 6070 www.eren.doe.gov/femp/techassist/ Phone: (865) 574-9337 savenergyprog.html National Association of Regulatory Utility Fax: (865) 574-9329 Commissioners [email protected] FEMP Software and Analytical Tools www.naruc.org www.eren.doe.gov/femp/techassist/ softwaretools/softwaretools.html Institute of Electrical and Electronics Engineers www.ieee.org DOE Software and Analytical Tools www.eren.doe.gov/buildings/tools_directory/ Federal Incentives for Commercial Solar Applications www.mdv-seia.org/federal_incentives.htm Green Power Network — State Net Metering Programs www.eren.doe.gov/greenpower/netmetering/ Produced for the index.shtml Distributed Utility Associates, Livermore, California, U.S. Department contributed to the preparation of this guide. Making Connections: Case Studies of of Energy by the National Renewable Energy Interconnection Barriers and their Impact on Laboratory, Distributed Power Projects a DOE national www.nrel.gov/docs/fy00osti/28053.pdf laboratory DOE/GO-102002-1520 May 2002 Printed with a renewable-source ink on paper containing at least 50% wastepaper, including 20% postconsumer waste