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A Closer Look

Consumer Choice and Cleaner Electricity: Why the Power Scorecard is Needed

Our daily use of electricity creates more pollution than this planet has ever seen. Even worse, the planet's climate and ecosystems are changing in ways that will harm future generations even more than ourselves. Until recently, consumers had little choice about their electricity providers. But now there is an opportunity to support cleaner, healthier power supplies.

As new companies enter into the power market and existing utilities evolve to meet the challenge, consumers now have the chance to choose among electricity providers and choose cleaner power. The electric power industry is complex, so the Power Scorecard is providing consumers with the tools to understand the environmental implications of their choice, and to act on their preferences. It can help both electricity buyers and sellers take advantage of new opportunities in choosing cleaner power supplies.

Pennsylvania is among the first states to open up electricity markets to competition. California's 30 million electric consumers are already selecting their electricity supplier and New York and many New England states are phasing in full-scale retail choice. If these markets will consider environmental impacts, consumer friendly tools like the Power Scorecard must be made widely available.

The Power Scorecard: An Evaluation Tool

The Power Scorecard is an evaluation tool that grades, on a scale of zero to ten generally, the relative environmental impacts of the resources used to produce an electricity product. A lower score means that the product produces less pollution and impact on the environment and human health. A high score means the product creates more smog, acid rain, land degradation and polluted water supplies. The Power Scorecard also identifies those electricity products that promise to invest in the construction of new low environmental impact renewable energy generation and those that offer other environmental enhancements, such as commitments to energy efficiency and purchases of pollution credits to offset the emission impacts from specific plants (e.g., by permanently retiring sulfur dioxide emission allowances).

The Power Scorecard is intended to augment the Green-e* by allowing consumers to learn more about each of the supply options carrying a Green-e label. It will also provide information about products not labeled with the Green-e.

*The Green-e program certifies that products bearing the Green-e logo meet the minimum environmental and consumer protection standards established by the non-profit Center for Resource Solutions.

The Scoring System

Scoring is calibrated with reference scores of four and ten. A score of four represents, for any performance category, either the lowest impact from fossil technology or the mid-range of impacts across all technologies. A score of ten is assigned to the most significantly severe impacts from electric generation.

The eight performance area scores for each supply resource are averaged to create an overall resource score -- and the scores of each resource supply are combined (in proportion to their product contribution) to produce a product score. Thermal and solar power supply resources are scored on the same eight air, water and land criteria; hydroelectric and wind facilities are scored on the same air criterion with water and land impacts scored by measuring site-specific performance.

Environmental enhancements available in some electric products are also scored, including supplier commitments to: 1) invest (within 12 months) in new renewable energy projects, 2) provide energy efficiency services, 3) acquire air emission offsets (e.g., by purchasing and permanently retiring sulfur dioxide emission allowances).

Products are rated from excellent to unacceptable based on:

  1. their environmental performance scores
  2. the degree to which new renewable resources are included in their offer

Plant-specific data in each performance area are requested from retailers. Responses are "scored" from zero to ten on performance area profiles developed from a detailed analysis of power generating technologies. If marketers can not provide data on emissions or other evaluation criteria, the Power Scorecard can grade products on the basis of technologies and fuel type.

The specific criteria used to develop the scores can be found in the Power Scorecard Methodology Report. To download this report:

1. Choose one of the formats below, and right click the link.
2. A menu will appear next to your cursor. Select "Save Target As..." (Internet Explorer) or "Save Link As..." (Netscape) from the menu.
3. A dialog box will pop up. Choose the location where you want the file saved on your computer. You have the option of renaming the file. When you are finished, press the "Save" button to begin download.

The table below shows default scores used for each generating technology.
Power Scorecard Default Scores by Technology Default Score Default
Solar: Distributed Photovoltaic (e.g., rooftop/building integrated) 0.0 Excellent
Wind Turbine Plant: low land impact
Geothermal: binary technology
Wind Turbine Plant: poorly sited
Solar: central station photovoltaic (i.e., site dedicated to PV)
Very Good
Landfill Gas: internal combustion engine, high nitrogen oxide emission rate
Very Good
Low Impact Hydropower (certified by Low Impact Hydropower Institute)
Very Good
Geothermal: flash technology
Very Good
Biomass: certified sustainable fuel, with nitrogen oxide controls
Very Good
Biomass: certified sustainable fuel, with high nitrogen oxide emissions
Very Good
Biomass: some climate change benefit*, "clean supply", with nitrogen oxide controls
Hydropower Plant; private, post-1986 FERC license
Biomass: high nitrogen oxide, some climate change benefit*, mixed supply
Natural Gas: combined cycle, with nitrogen oxide controls
Natural Gas: combined cycle
Biomass: wood-fueled, high nitrogen oxide, biomass not replaced
Gas Fired Steam Electric, with nitrogen oxide controls 4.6 Fair
Gas Fired Steam Electric 4.7
Hydropower Plant: FERC license before 1987 (default)
Natural Gas: combustion turbine
Biomass: wood-fueled, high nitrogen oxide, no climate change benefit*
Oil-Fired Steam Electric: 0.5% sulfur content
Oil-Fired Steam Electric: 1.0% sulfur content
Oil-Fired Combustion Turbine
Oil-Fired Steam Electric
Coal With Flue Gas Desulfurization (low mercury content)
Coal With Flue Gas Desulfurization (high mercury content)
Coal-Fired Steam Electric (default)
Nuclear Power

*The global climate change impact score of biomass is based upon the net impact of the fuel source on global climate change agents (CO2 and methane emissions).

The Power Scorecard reflects the collective exercise of expert judgement by the sponsoring organizations, based on its interpretation of available data and assessment of its accuracy and reliability, and application of state-of-the-art techniques in the identification and quantification of environmental impacts of electric power generation technologies. The Power Scorecard ratings appearing on this website may be based on assumptions made by the sponsoring organizations as to the composition, fuel sources, technologies, and associated environmental attributes of particular products where such information is unknown to or has not been provided by the supplier, and where such information is not publicly available. However, every effort is made to validate the information used in rating products with the supplier.

For more information about the Power Scorecard, contact:

Sam Swanson
Director, Power Scorecard Project
Pace Energy Project
PO Box 4245
Burlington, VT 05406-4245

e-mail: Power Scorecard@aol.com


©2000 Pace University, White Plains, New York
Design ©2000 Baseline Institute, Lafayette, Colorado