About the Power Content Label

AB 162 (Statute of 2009) and Senate Bill 1305 (Statutes of 1997) require retail electricity suppliers to disclose information to California consumers about the energy resources used to generate the electricity they sell. As directed, the Energy Commission created a user-friendly way of displaying this information called the Power Content Label. This label provides you with reliable information about the energy resources used to generate electricity, enabling you to easily compare the power content of one electric service product with that of others.

You can think of the power content label as a "nutrition label" for electricity. The power content label provides information about the energy resources used to generate electricity that is put into the power grid. Just as a nutrition label provides information about the food you eat, the power content label provides information about your electricity sources.


What information does the power content label provide?

Electricity can be generated in a number of ways. It can come from renewable resources such as biomass and waste, geothermal heat or steam, solar energy, rivers or small hydroelectric reservoirs, and wind energy; or, it can be produced from resources such as coal, large hydroelectric reservoirs, natural gas, or nuclear fuels. The Power Content Label describes the sources of electricity that are put into the power grid. Each electricity supplier must display information about the energy resources represented by their contracts with electricity generators.

The power content label cannot tell you about the electricity that you use in your home; instead, it tells you about the resources mix your energy dollars are being spent on. If you purchase electricity generated using natural gas, for example, you are paying a natural gas-fired plant to generate electricity and to feed it into the main power grid. Since it is impossible to track the flow of electricity on the grid, there is no way to identify the actual power plant that produced the electricity you consume in your home. But it is possible to track the dollars you pay for electricity. Your electricity dollars will support electricity generation from various energy resources in the proportions listed on the Power Content Label..

See below for a more detailed explanation of the information contained in the Power Content Label.


Where and when will I see the Power Content Label?

Electricity suppliers are required to include the Power Content Label in all advertisements sent to you in the mail or over the Internet. Furthermore, your electricity supplier must send you annual updates for the electric service product you're purchasing by October 1st each year. If there have been any changes in what the electricity supplier is able to provide you, you will learn of them in these updates.

The Power Content Label cannot tell you about the electricity that you use in your home; instead, it tells you about the resources mix your energy dollars are being spent on. If you purchase electricity generated using natural gas, for example, you are paying a natural gas-fired plant to generate electricity and to feed it into the main power grid. Since it is impossible to track the flow of electricity on the grid, however, there is no way to identify the actual power plant that produced the electricity you consume in your home. But it is possible to track the dollars you pay for electricity. Your electricity dollars will support electricity generation from various energy resources in the proportions listed on the Power Content Label.

Your electricity choice does make a difference, because you decide what kinds of electricity are fed into the electricity grid. Over the long term, your purchasing decisions will help determine what kinds of power plants are built to serve California's electricity needs.


Aren't the utilities required to purchase electricity from renewable resources?

Yes. California’s Renewables Portfolio Standard (RPS) requires all electricity retail suppliers to obtain 50 percent of their electricity from eligible renewable resources by 2030, and to make incremental steps toward that goal in the meantime. These include solar, wind, geothermal, biomass, small hydroelectric facilities and other sources of renewable energy. Renewable energy resources will help the state reach its goals of reducing greenhouse gas emissions that affect the global climate.


Does the Power Content Label correspond with RPS?

Put simply, no. RPS uses a different methodology than that of the Power Content Label. RPS compliance is calculated over three year periods by tracking the retirement of renewable energy credits.

The Power Content Label, on the other hand, is based on annual electricity procurements, and these do not necessarily match with RPS’ compliance periods. However, the Power Content Label serves a different function. It is designed to be a simple, quick check of your electric retail supplier’s power sources and renewable energy profile, and its performance relative to other retail suppliers and the state as a whole.


A guide to the Power Content Label:

typical Power Content Label

Column A (Energy Resources)

This column lists the different energy resources that can be used to generate electricity, including eligible renewable resources and other resources. For a description of each resource type, see the section titled Energy Resources below.

Column B (Power Mix)

This column displays the actual mix of electricity purchased by your utility in a given year, broken out by resource type.

Column C (California Power Mix)

This column displays the mix of resources used in California for a given year. This information is provided as a reference point for you to compare your electricity retail supplier’s resource mix to the overall resource mix of the state. The Energy Commission publishes Total System Power data each year, based on reports submitted to the Energy Commission by electrical generation facilities.



Energy Resources

  • Eligible Renewable: Renewable resources are energy resources that either cannot be used up or are quickly replenished through natural processes. In California, biomass and waste, geothermal, solar, small hydroelectric, and wind energy resources are all considered eligible renewable resources under California's Renewables Portfolio Standard.

    • Biomass and Biowaste - Biomass fuels are residues produced from logging, mill operations and the manufacture of wood, pulp, paper, and fiberboard, agricultural field and orchard crops, livestock and poultry growing operations, food processing, and demolition (urban wood waste). Waste fuels include combustible residues from organic materials such as household, agricultural, industrial, and food waste. Municipal solid and liquid wastes comprise another subcategory of bio-waste. In general, biomass and bio-waste fuels are converted to electricity by burning the fuel in a boiler, which generates the steam used to turn a turbine generator. These fuels may also be gasified and burned to produce electricity.

    • Geothermal - Geothermal electricity is produced using heat from deep within the earth (often evidenced by the presence of hot springs or geysers). This heat is captured and used to make steam to turn an electric generation turbine.

    • Solar - Solar electricity can be generated in two ways. One way involves focusing the heat of the sun on a central point that heats up. This heat is then used to produce steam, which turns an electricity turbine. Another way to harness solar power for electricity is through photovoltaic cells, such as those seen on rooftops. Photovoltaic cells directly convert sunlight to electricity. Though each photovoltaic panel produces a relatively small amount of electricity, they can be grouped together to produce larger amounts.

    • Eligible Hydroelectric Hydroelectric power plants transform the energy of falling water into electrical energy through the use of water wheels or hydraulic turbines. Eligible hydroelectric makes use of smaller generating facilities, typically with a capacity of 30 megawatts or fewer, and may either use a small dam or river flows to harness the energy of the moving water, or small facilities that make use of water supply or conveyance systems, or incremental increases to hydroelectric facilities that result from repowering.

    • Wind - Wind energy is derived from the movement of air caused by the uneven heating of the earth's surface by the sun. Power from the wind is captured using wind turbines – blades that turn as the wind blows – to generate electricity.

  • Coal - Coal is a form of carbon that was created over millions of years from decaying plants. Coal is normally used in a pulverized solid form to fuel a conventional boiler, generating steam, which is then used to produce electricity. Most of the coal-fired power plants that make electricity from California are from plants located out of state but are owned by in-state utility companies. State law restricts utilities from new purchase agreements with coal plants because of climate change concerns.

  • Large Hydroelectric This technology is essentially the same as eligible hydroelectric except that it operates on a larger scale—typically these facilities are larger than 30 megawatts. Whereas smaller hydroelectric facilities may be positioned on a river or canal, a large hydroelectric facility is typically located on a large dam. Although large hydroelectric facilities do not emit greenhouse gases, these facilities are not considered eligible renewable resources.

  • Natural Gas - A fossil fuel that comes from deep within the earth, natural gas originates from ancient decaying plant matter. It is extracted from the earth, processed, and burned to produce electricity. It is currently the largest source of electricity used in California.

  • Nuclear - Nuclear energy is derived from the splitting or "fissioning" of uranium atoms. Uranium is mined, processed to increase the amount of fissionable material, and made into fuel rods which are then placed in nuclear reactors. As the uranium atoms split inside the reactor, they generate heat which is converted to steam and used to generate electricity.

  • Other - This category includes other energy resources not categorized as any of the other listed categories. This category may include, for example, petroleum-fired plants (which have been almost entirely phased out in California).

  • Unspecified Sources of Power - This refers to electricity that is not traceable to a specific generating facility, such as electricity traded through open market transactions. Unspecified sources of power are typically a mix of resource types, and may include renewables.


If you have further questions about the Power Content Label, please contact Kevin Chou at 916-653-1628 or kevin.chou@energy.ca.gov.