DOCSLIB.ORG

Making the Connection—Key Issues in Connecting A

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Making the Connection—Key Issues in Connecting A MAKING THE CONNECTION Key Issues in Connecting a Photovoltaic System to the Utility Grid WE’VE COME A LONG WAY Connecting residential or small com- a builder, code expert, utility engi- mercial photovoltaic (PV) systems neer, regulator, legislator, or private to an existing utility grid has come citizen. If not properly addressed, a long way in recent years. Experts any one of these crucial issues could within the PV industry have solved hinder or halt the installation of a many earlier problems, bringing us PV system. to the point today where we know As we discuss the relevant issues how to install, operate, and maintain under the two main categories of PV systems safely and conveniently. code issues and utility issues, But governments, communities, and remember the bottom line: many utilities who are not yet familiar with former technical obstacles to using PV systems have legitimate concerns PV systems no longer exist, and that we must address through educa- critical problems raised in the past tion and support. are being successfully resolved. This brochure will help you under- stand the issues that surround PV interconnections, whether you are CODE ISSUES Building Codes has been steady during the last sev- eral years. We now see commercial Local building authorities rely on products designed for building nationally developed building codes systems—such as PV roofing that delineate required safe-building materials and PV curtain wall practices. Building inspectors are products—that are included in concerned with the proper construc- construction plans. In addition, tion of safe buildings. Of primary the mounting of systems on flat interest is ensuring that a PV system roofs has been greatly simplified. or structure has been installed correctly. For example, the system must be fastened according to approved design drawings so that it Solar Depot, Inc./PIX04479 won't cause the roof to leak or be blown off the roof, leading to serious structural damage. Before embarking on a PV installation project, the appropriate code officials Solutions—The development of should be consulted to ensure com- innovative building-integrated PV pliance with all local codes. systems that meet building codes 1 Local Covenants Electrical Codes Some communities may adopt restric- The National Electrical Code (NEC), tions, primarily for aesthetic reasons, published by the National Fire that make it difficult or impossible Protection Association, is designed to install PV modules. If visual to prevent electrical shock and fire aspects are not properly addressed, hazards associated with electrical community representatives are not systems. Some utility-interconnected likely to look favorably on the wide- PV systems operate at direct-current spread use of PV within their (dc) voltages exceeding 200 volts community. If a community has before being inverted to standard a particularly restrictive covenant alternating-current (ac) voltage. with respect to solar systems, it may Direct-current systems are not as be necessary common, and their safe operation to meet with requires “dc rated” hardware. the covenants board to Solutions—In 1984, PV systems NREL/PIX05777 explain the achieved the status of a special planned instal- equipment article in Article 690 lation and of the NEC. Article 690 carefully address spe- spells out requirements for making cific concerns. PV systems compliant with the NEC. A guide for recommended practices Solutions— based on the NEC provides practical Increasingly, information on designing and instal- U.S. commu- ling safe, reliable, code-compliant nities are being PV systems (see PV Power Systems, designed with NEC: Suggested Practices, SAND96- allowances for solar energy written 2797). Only within the last few into the established covenants. The years have fully code-compliant city of Davis, in northern California, systems been available. However, is a model community that has many systems that comply with the pioneered these types of covenants. code have operated safely for more As more examples of model cove- than 10 years. PV system installers nants become widely publicized, must understand the Article 690 the public will be more open to requirements, and local code institutionalizing these measures in authorities unfamiliar with PV their communities. Well-prepared systems must be educated. materials, such as a sketch of a proposed installation or a photo- Representatives from the solar energy graph of a similar installation, industry have actively guided the can help allay the concerns of a revisions of NEC Article 690 for covenants board. many years. The most recent 1999 version will be released in late summer 1998. 2 The NEC requires that all As another example of improved equipment be listed by a products, the ac PV module is a recognized listing agency— recent innovation that converts for example, Underwriters dc power to standard ac before it Laboratories. Several PV leaves the module, which eliminates inverters are now listed, the need for high-voltage dc wiring Solar Associates/PIX04472 Design making it possible to and allows for PV systems as small install a fully code-compli- as 100 watts. ant PV system acceptable to most code authorities. UTILITY ISSUES Power Quality Solutions—Any electronic appliance, such as a PV inverter, that is FCC Power quality “noise” is any electrical Class B compliant means that it has energy that interferes with other passed the required tests to meet the electrical appliances operated by the FCC regulations for high-frequency customer and neighbors on the same electronic noise. The Institute of transformer. The Federal Communi- Electrical and Electronic Engineers cations Commission (FCC) is con- (IEEE) also has power-quality stan- cerned with power-quality noise that dards, such as IEEE 519, Recom- affects communications. Utility com- mended Practices and Requirements panies are also concerned because for Harmonic Control in Electrical they seek to provide high- quality service to their cus- tomers. In particular, utilities care about such issues as harmonic distortion, power factor, and flicker. For a home, power is delivered at 120/240 volts ac at 60 Gretz, Warren NREL/PIX04167 cycles per second. Any electric service not at that rating can interfere with the proper operation of some appliances. A PV inverter that con- Power Systems. The Underwriters verts dc power from PV modules Laboratories standard for listing into usable ac power for a house a PV inverter includes testing for can also inject noise. If a utility power quality so that listed PV customer’s power-quality problem inverters will conform to applicable is traced to a PV inverter, the utility requirements. can shut down the PV equipment until the issue is resolved. 3 Metering Agreements can easily wipe out any economic benefit a small PV system could Metering agreements directly affect provide a homeowner. Most utilities the bottom-line economics of the PV require special metering to measure system. For example, special meter- power flowing in both directions— ing and additional metering charges into the house and into the grid. Many utilities impose additional charges on utility-interconnected The ABCs of Net Metering PV systems, including “standby” Under federal law, utilities must allow independent power producers to intercon- charges or higher “minimum nect with the utility grid and must purchase monthly” charges. any excess electricity they generate. Many And for the states have gone beyond the minimum excess electricity requirements of the federal law by allowing generated, utilities “net metering” for customers with PV normally pay the systems. Where available, the customer customer a wholesale is billed only for the “net” electricity rate, rather than the purchased from the utility over the much higher retail rate. entire billing period—that is, the difference between the electricity Solutions—Some utili- coming from the utility grid and the ties have established Available electricity generated by the PV system. If the “net” amount is posi- metering and accounting Not available tive, the customer pays the utility at the retail rate on the net kilowatt- arrangements that make grid- Z8-B317505 hours of energy used. If the “net” amount is negative, the customer either connected PV systems more is credited on the next bill for the excess electricity, or is paid for the excess economical. For example, some electricity at the wholesale rate. states have adopted net-metering Dual metering is an alternative, where customers or their utility purchase and policies (see box) that allow utility install two non-reversing meters that measure electrical flow in each direction. customers to use their PV genera- This adds significant expense to installing a PV system. Homeowners pay for tion to offset retail purchases over all the electricity from the utility at the retail rate—not just the net amount. an entire billing period, or over an And the utility only pays them the much lower wholesale rate on the electricity entire year. Net metering improves fed back to the utility. the economics of PV generation by allowing customers to capture the Faced with the alternative between net metering and the traditional dual-meter- retail value of electricity for most or ing approach, many states, utility commissions, and utilities have opted for net all of their PV generation. In addi- metering because it is less expensive for all involved. Some opponents believe it tion, some utilities offer time-of-day imposes financial burdens on utilities or their non-participating customers. pricing, which results in higher Studies have shown that the quantity of PV relative to the size of the utility's prices during “peak” daytime hours revenues is minimal—even without considering reduced costs of meter hard- and lower prices during “off-peak” ware, interconnection, meter reading, and billing. These studies do not include nighttime hours. Time-of-day pricing the issue of peak-shaving capability or the environmental, distribution, and can provide substantial bill savings fuel-diversity benefits provided by distributed, small-scale, renewable-energy to customers with PV systems—by systems.
Load more

Recommended publications
  • How Smart Metering and Smart Charging May Help a Local Energy Community in Collective Self-Consumption in Presence of Electric Vehicles
    energies Article How Smart Metering and Smart Charging may Help a Local Energy Community in Collective Self-Consumption in Presence of Electric Vehicles Giuseppe Barone 1 , Giovanni Brusco 1 , Daniele Menniti 1 , Anna Pinnarelli 1 , Gaetano Polizzi 1, Nicola Sorrentino 1, Pasquale Vizza 1 and Alessandro Burgio 2,* 1 Department of Mechanical, Energy and Management Engineering, University of Calabria, 87036 Rende, Italy; [email protected] (G.B.); [email protected] (G.B.); [email protected] (D.M.); [email protected] (A.P.); [email protected] (G.P.); [email protected] (N.S.); [email protected] (P.V.) 2 Independent Researcher, 87036 Rende, Italy * Correspondence: [email protected] Received: 11 July 2020; Accepted: 4 August 2020; Published: 12 August 2020 Abstract: The 2018/2001/EU renewable energy directive (RED II) underlined the strategic role of energy communities in the EU transition process towards sustainable and renewable energy. In line with the path traced by RED II, this paper proposes a solution that may help local energy communities in increasing self-consumption. The proposed solution is based on the combination of smart metering and smart charging. A set of smart meters returns the profile of each member of the community with a time resolution of 5 s; the aggregator calculates the community profile and regulates the charging of electric vehicles accordingly. An experimental test is performed on a local community composed of four users, where the first is a consumer with a Nissan Leaf, whereas the remaining three users are prosumers with a photovoltaic generator mounted on the roof of their home.
    [Show full text]
  • Italy's Effort to Phase out and Rationalise Its Fossil Fuel Subsidies
    ITALY’S EFFORT TO PHASE OUT AND RATIONALISE ITS FOSSIL-FUEL SUBSIDIES A REPORT ON THE G20 PEER-REVIEW OF INEFFICIENT FOSSIL-FUEL SUBSIDIES THAT ENCOURAGE WASTEFUL CONSUMPTION IN ITALY PREPARED BY THE MEMBERS OF THE PEER-REVIEW TEAM: ARGENTINA, CANADA, CHILE, CHINA, FRANCE, GERMANY, INDONESIA, NETHERLANDS, NEW ZEALAND, IEA, UN ENVIRONMENT, IISD, EUROPEAN ENERGY RETAILERS, GREEN BUDGET EUROPE, THE OECD (CHAIR OF THE PEER-REVIEW) AND SELECTED EXPERTS APRIL 2019 1 │ Italy’s effort to phase out and rationalise its fossil-fuel subsidies A report on the G20 peer-review of inefficient fossil-fuel subsidies that encourage wasteful consumption in Italy Prepared by the members of the peer-review team: Argentina, Canada, Chile, China, France, Germany, Indonesia, Netherlands, New Zealand, IEA, UN Environment, IISD, European Energy Retailers, Green Budget Europe, the OECD (Chair of the peer-review) and selected experts ITALY’S EFFORT TO PHASE OUT AND RATIONALISE ITS FOSSIL FUEL SUBSIDIES 2 │ Table of contents Acronyms and Abbreviations ............................................................................................................... 4 Executive Summary .............................................................................................................................. 5 1. Introduction ....................................................................................................................................... 7 1.1. Background and context ..............................................................................................................
    [Show full text]
  • Propane & Net Zero
    PROPANE & NET ZERO WHY NET ZERO IS IMPORTANT “Net zero” refers to achieving an overall balance between emissions produced and emissions taken out of the atmosphere. Propane can help reduce CO2 emissions by replacing heavy carbons like coal, oil and even wood. Its affordability also ensures every consumer can share equitably in the benefits propane brings. PROPANE DECARBONIZES PROPANE ENSURES EQUITY Clean and renewable energy like propane Access to clean, affordable and renewable energy accelerates decarbonization. like propane ensures equity on the path to zero. Δ Decarbonization requires more cleaner energy options. The Δ Urban and rural low-income households, especially U.S. Department of Energy’s (DOE) Office of Scientific and African American and Latinx households, spend roughly Technical Information says that large emissions reductions three times as much of their income on energy costs are achievable through a broad range of opportunities, as non-low-income households. In February 2021, EIA including the use of low- or zero-carbon alternatives. reported that electricity was 68% more expensive per million BTUs than propane. Δ The electric grid isn’t always the cleanest answer. Currently, propane-fueled medium- and heavy-duty Δ Energy should be affordable, so that no one has to vehicles provide a lower carbon footprint solution in 38 go without, but the share of income that low-income U.S. states when compared to medium- and heavy-duty households spent on electricity rose by 1/3 in the last EVs charged from the electrical grid. decade. Δ Propane is innovating everyday. It is, in fact, the new Δ Everyone should have access to clean energy and home diesel.
    [Show full text]
  • An Overview of Behind-The-Meter Solar-Plus-Storage
    AN OVERVIEW OF BEHIND-THE- METER SOLAR-PLUS-STORAGE REGULATORY DESIGN Approaches and Case Studies to Inform International Applications Owen Zinaman, Thomas Bowen, and Alexandra Aznar National Renewable Energy Laboratory March 2020 A product of the USAID-NREL partnership Contract No. IAG-17-2050 NOTICE This work was authored, in part, by the National Renewable Energy Laboratory (NREL), operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE- AC36-08GO28308. Funding provided by the United States Agency for International Development (USAID) under Contract No. IAG-17-2050. The views expressed in this report do not necessarily represent the views of the DOE or the U.S. Government, or any agency thereof, including USAID. This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. U.S. Department of Energy (DOE) reports produced after 1991 and a growing number of pre-1991 documents are available free via www.OSTI.gov. Cover photo from iStock 471670114. NREL prints on paper that contains recycled content. Acknowledgments The authors thank Anurag Mishra and Sarah Lawson from the U.S. Agency for International Development (USAID) Office of Energy and Infrastructure for their support of this work. We also wish to thank the following individuals for their detailed review comments, insights, and contributions to this report (names listed alphabetically by organization and last name). Clean Energy Group—Seth Mullendore E3 Analytics—Toby
    [Show full text]
  • Annual Net Metering Report for 2019
    ANNUAL NET METERING REPORT FOR 2019 April 3, 2020 Manager, Energy Department Missouri Public Service Commission Pursuant to 20 CSR 4240-20.065 (10)(A), Evergy Missouri Metro and Evergy Missouri West submits the following Annual Net Metering Report for 2019. Item (A) 1 of the following table represents the total number of customer-generator facilities connected to our distribution system at year end. Item (A) 2 represents the total estimated generating capacity of customer-generators that are connected to our distribution system. Item (A) 3 represents the total estimated net kilowatt-hours received from customer- generators. Generating Net kWhs Customers Capacity (kW) Received (A) 1 (A) 2 (A) 3 Evergy Missouri Metro 2,107 31,804.21 10,961,098 Evergy Missouri West 2,560 45,282.12 20,302,687 Total 4,667 77,086.32 31,263,876 Also, pursuant to 20 CSR 4240-20.065 (10)(B), please find enclosed a copy of the standard information, Attachment A, regarding net metering and interconnection requirements provided to customers or posted on the Company’s website. This information can also be found at the following link: https://www.evergy.com/smart-energy/renewable-resources/private-solar-and-net-metering Please let me know if you have any questions. Sincerely, Lisa Casteel Regulatory Affairs 816-556-2705 Public Attachment A Public FILED Missouri Public Service Commission EE-2019-0056; JE-2019-0028 FILED Missouri Public Service Commission EE-2019-0056; JE-2019-0028 FILED Missouri Public Service Commission EE-2019-0056; JE-2019-0028 KCP&L GREATER MISSOURI OPERATIONS COMPANY P.S.C.
    [Show full text]
  • GHG Protocol Scope 2 Guidance
    GHG Protocol Scope 2 Guidance An amendment to the GHG Protocol Corporate Standard AUTHOR Mary Sotos GHG PROTOCOL TEAM Pankaj Bhatia, World Resources Institute Cynthia Cummis, World Resources Institute Mark Didden, World Business Council for Sustainable Development Alex Kovac, World Resources Institute Josh Ryor, World Resources Institute Amanda Stevens, World Resources Institute Table of Contents 1 Introduction 4 2 Business Goals 14 3 Accounting and Reporting Principles 20 4 Scope 2 Accounting Methods 24 5 Identifying Scope 2 Emissions and Setting the Scope 2 Boundary 32 6 Calculating Emissions 42 7 Accounting and Reporting Requirements 58 8 Recommended Reporting on Instrument Features and Policy Context 66 9 Setting Reduction Targets and Tracking Emissions Over Time 74 BACKGROUND READING 10 Key Concepts and Background in Energy Attribute Certificates and Claims 78 11 How Companies Can Drive Electricity Supply Changes with the Market-Based Method 88 AppENDICES A Accounting for Steam, Heat, and Cooling 94 B Accounting for Energy-Related Emissions Throughout the Value Chain 96 Abbreviations 98 Glossary 99 References 108 Recognitions 111 1 Detailed Table of Contents 1 INTRODUCTION 4 4 SCOPE 2 ACCOUNTING METHODS 24 1.1 The GHG Protocol 5 4.1 Approaches to accounting scope 2 25 1.2 The Corporate Standard’s 4.2 Emission rate approach 27 approach to scope 2 emissions 5 4.3 The decision-making value of each 1.3 Key questions on scope 2 accounting method’s results 28 and reporting 6 1.4 Purpose of this Guidance 7 5 IDENTIFYING SCOPE 2 EMISSIONS
    [Show full text]
  • USAID Energy Storage Decision Guide for Policymakers
    USAID ENERGY STORAGE FOR DECISION GUIDE POLICYMAKERS www.greeningthegrid.org | www.nrel.gov/usaid-partnership USAID ENERGY STORAGE FO R DECISION GUIDE P OLICYMAKERS Authors Ilya Chernyakhovskiy, Thomas Bowen, Carishma Gokhale-Welch, Owen Zinaman National Renewable Energy Laboratory July 2021 View the companion report: USAID Grid-Scale Energy Storage Technologies Primer www.greeningthegrid.org | www.nrel.gov/usaid-partnership Prepared by NOTICE This work was authored, in part, by the National Renewable Energy Laboratory (NREL), operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding provided by the United States Agency for International Development (USAID) under Contract No. IAG-17-2050. The views expressed in this report do not necessarily represent the views of the DOE or the U.S. Government, or any agency thereof, including USAID. This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. U.S. Department of Energy (DOE) reports produced after 1991 and a growing number of pre-1991 documents are available free via www.OSTI.gov. Front cover: photo from iStock 506609532; Back cover: photo from iStock 506611252 NREL prints on paper that contains recycled content. Acknowledgments The authors are greatly indebted to several individuals for their support and guidance. We wish to thank Sarah Lawson, Andrew Fang, and Sarah Dimson at the U.S. Agency for International Development (USAID) for their thoughtful reviews. We also wish to thank Peerapat Vithayasrichareon, Jacques Warichet, Enrique Gutierrez Tavarez, and Luis Lopez at the International Energy Agency, and Dr.
    [Show full text]
  • Net Metering: in Brief
    Net Metering: In Brief November 14, 2019 Congressional Research Service https://crsreports.congress.gov R46010 SUMMARY R46010 Net Metering: In Brief November 14, 2019 Net metering is a policy that allows electricity customers with their own generation capacity to be financially compensated for the energy they produce. Net metering is widely regarded as having Ashley J. Lawson an important role in deployment of distributed generation (DG), especially solar energy. State Analyst in Energy Policy and local governments have authority to establish net metering policies, and some have done so for many years. Congress took action to encourage net metering in the Energy Policy Act of 2005 (EPACT05), and the policy now exists, in some form, in 45 states. Recent state net metering policy modifications, and potential effects on solar energy deployment, may be relevant to congressional discussions regarding the role of renewable energy sources in the nation’s electricity system. Solar photovoltaic panels (e.g., rooftop solar) accounted for 97% of the generation capacity participating in net metering programs in 2018. Net metering participation roughly quadrupled from 2013 to 2018, according to data from the U.S. Energy Information Administration. Hawaii has the highest participation rate of any state, with 15% of electricity customers participating in net metering in 2018. In a majority of states, however, net metering customers account for less than 1% of total electricity customers. States differ in the way net metering customers are compensated. A common method is the retail rate, under which energy from net metering capacity offsets energy consumed from the grid in a one-to-one fashion.
    [Show full text]
  • Comparative Analysis of Net Metering and Feed in Tariff Schemes for 50Kw Solar Photovoltaic Distributed Generation System at Mahad Ganesh Dahale*, Prof
    IJRECE VOL. 6 ISSUE 2 APR.-JUNE 2018 ISSN: 2393-9028 (PRINT) | ISSN: 2348-2281 (ONLINE) Comparative Analysis of Net Metering and Feed in Tariff Schemes for 50kw Solar Photovoltaic Distributed Generation System at Mahad Ganesh Dahale*, Prof. Sunil Gaikwad and Prof. Dr. Y.P. Nerkar Department of Electrical Engineering, PVG's COET, Pune, India Abstract: Solar Photovoltaic (PV) system compared to its takes place through grid. Feed in tariff (FiT) or renewable scenario a decade ago has made a great impact in energy energy payment method is applied to those distributed energy production. Government provides several benefits to the systems producing electricity by their own. FiT has two tariffs customers in terms of subsidies, benefits in income-taxes and i.e. for its generation and its own consumption.Both methods many other such benefits. Tariff by Net metering i.e. Net metering and FiT prove to be cost and energy effective schemeregulated by the Government provides benefits to the and provide reduction in CO2 emission. However, the latter consumer applicable for various distributed generation system. provides more effective result in terms of cost and energy. In this paper, a new scheme of Feed in Tariff (FiT) for metering the total amount of energy generated has been This paper provides the statistical analysis between Net metering and Feed in Tariff applied on a 50kWp solar roof top discussed. A case study on 50 kW Laxmi Ice factory at Mahad, Maharashtra is considered in this paper. A PV application. This is applied at Laxmi Ice Factory in Mahad, Maharashtra at an altitude 11m and latitude 18.1N and MATLAB/Simulink model consisting 50 kW solar PV system, FiT& Net metering, solar radiance value is simulated.
    [Show full text]
  • REFORMING NET METERING Tom Tanton PROVIDING a BRIGHT and EQUITABLE FUTURE
    ALEC.ORG REFORMING NET METERING Tom Tanton PROVIDING A BRIGHT AND EQUITABLE FUTURE WWW.ALEC.ORG 1 About the American Legislative Exchange Council The American Legislative Exchange Council (ALEC) is the nation’s largest nonpartisan, individual membership organization of state legislators, with more than 2,000 members across the nation. ALEC is committed to advancing the fundamental principles of limited government, free markets and federalism at the state level through a nonpartisan public-private partnership of America’s state legislators, members of the private sector, and the general public. ALEC is classified by the Internal Revenue Service as a 501(c)(3) nonprofit, public policy, and educational organization. Individuals, philanthropic foundations, corporations, companies, or associations are eligible to support ALEC’s work through tax-deductible gifts. About the ALEC Task Force on Energy, Environment and Agriculture The ALEC Task Force on Energy, Environment and Agriculture promotes the mutually beneficial link between a robust economy and a healthy environment, and seeks to enhance the quality and use of our natural and agricultural resources for the benefit of human health and well-being. The Task Force works with more than 250 public and private-sector members to develop best practice model policy on issues such as climate change, agriculture, environmental health, regulatory reform, federalism, chemical regulation, property rights, waste management, and public lands. John Eick is the task force director and can be reached at
    [Show full text]
  • DC Power Production, Delivery and Utilization
    DDCC PPowerower PProduction,roduction, DDeliveryelivery aandnd UUtilizationtilization An EPRI White Paper June 2006 AAnn EEPRIPRI WWhitehite PPaperaper DC Power Production, Delivery and Utilization This paper was prepared by Karen George of EPRI Solutions, Inc., based on technical material from: Arshad Mansoor, Vice President, EPRI Solutions Clark Gellings, Vice President—Innovation, EPRI Dan Rastler, Tech Leader, Distributed Resources, EPRI Don Von Dollen, Program Director, IntelliGrid, EPRI AAcknowledgementscknowledgements We would like to thank reviewers and contributors: Phil Barker, Principal Engineer, Nova Energy Specialists David Geary, Vice President, of Engineering, Baldwin Technologies, Inc. Haresh Kamath, EPRI Solutions Tom Key, Principal Technical Manager, EPRI Annabelle Pratt, Power Architect, Intel Corporation Mark Robinson, Vice President, Nextek Power Copyright ©2006 Electric Power Research Institute (EPRI), Palo Alto, CA USA June 2006 Page 2 AAnn EEPRIPRI WWhitehite PPaperaper DC Power Production, Delivery and Utilization Edison Redux: The New AC/DC Debate Thomas Edison’s nineteenth-century electric distribution sys- Several converging factors have spurred the recent interest in tem relied on direct current (DC) power generation, delivery, DC power delivery. One of the most important is that an in- and use. This pioneering system, however, turned out to be im- creasing number of microprocessor-based electronic devices practical and uneconomical, largely because in the 19th cen- use DC power internally, converted inside the device from tury, DC power generation was limited to a relatively low volt- standard AC supply. Another factor is that new distributed re- age potential and DC power could not be transmitted beyond sources such as solar photovoltaic (PV) arrays and fuel cells a mile.
    [Show full text]
  • Net Metering Policy Summary
    Net Metering Policy Summary State Authority Capacity Limits Carry‐over of Surcharge or Avoided Community Multiple Application NEG additional cost Cost or or virtual net accounts for connection Retail Rate metering (aggregate) for NEG Montana 69‐8‐601 50 kW Month‐to‐ No, prohibited in Retail No No IOUs that through month. Credit statute have 69‐8‐605, to utility at restructured MCA the end of in accordance the year with Title 69, chapter 8 Wyoming 37‐16‐ 25 kW Month‐to‐ No, prohibited in Month‐to‐ No No IOUs, electric 101 month. Credit statute month cooperatives, through to customer credited per and irrigation 37‐16‐ at the end of kWh at retail districts 104, WS the year rate*. Annually utility purchases at avoided‐cost rate Idaho Tariff 25 kW for Month‐to‐ $100 application Residential No May transfer IOUs have residential and month. fee. Net metering and small excess developed a (Idaho small Excess credits tariff — including commercial generation tariff to allow Power as commercial carry forward current rate customers, between net metering example. indefinitely structure and credited at meters that is Schedule 100 kW for until entirely interconnection retail rate. among approved by 84.) other rate used to offset requirements — Large customer the PUC classes consumption does not commercial accounts if represent and meters are Utility tariffs guarantee of agricultural on same limit to 0.1% in future pricing customers, primary baseline year credited at feeder, 85% located on avoided‐cost same rate contiguous property, and electricity is for customer Nevada NRS 1 MW Month‐to‐ For systems up to Either a No Hydro with a IOUs 704.766 – month or 25 kW, utility standard capacity up 704.775 Generation time of use.
    [Show full text]