Glossary & Useful Links

Cogeneration or Combined heat and power-CHP systems simply capture and utilize excess heat generated during the production of electric power. CHP systems offer economic, environmental and reliability-related advantages compared to power generation facilities that produce only electricity. Distributed power generation systems, which are frequently located near thermal loads, are particularly well suited for CHP applications.

Distributed generation-Distributed energy resources (DER) are parallel and stand-alone electric generation units located within the electric distribution system at or near the end user. DER can be beneficial to both electricity consumers and if the integration is properly engineered, the energy utility.

Emerging renewable technology - technology that uses a renewable power source, such as solar or wind energy, to generate electricity, and that has emerged beyond the research and development phase, is commercially available, and has significant commercial potential as determined by the Energy Commission. Emerging renewable technologies include photovoltaic, solar thermal electric, fuel cells using a renewable fuel, and small wind turbine technology no greater than 50 kilowatts in size.

Fuel cell - an advanced energy conversion device that combines hydrogen-bearing fuels with airborne oxygen in an electrochemical reaction to produce electricity very efficiently and with minimal environmental impact.

Geothermal - natural heat from within the earth, captured for production of electric power, space heating, or industrial steam.

Landfill gas (LFG) - gas produced by the breakdown of organic matter in a landfill (composed primarily of methane and carbon dioxide) or the technology that uses this gas to produce power.

Photovoltaic (PV) - a technology that uses a semiconductor to convert sunlight directly into electricity.

Renewable - a power source other than a conventional power source within the meaning of Section 2805 of the Public Utilities Code. Section 2805 states: " 'Conventional power source' means power derived from nuclear energy or the operation of a hydropower facility greater than 30 megawatts or the combustion of fossil fuels, unless cogeneration technology, as defined in Section 25134 of the Public Resources Code, is employed in the production of such power."

Small hydro electric- a facility employing one or more hydroelectric turbine generators, the sum capacity of which does not exceed 30 megawatts, except in the case of efficiency improvements or conduit hydroelectric facilities as described below. Pursuant to Public Utilities Code Section 399.12, Subdivision (b), an existing small hydroelectric generation facility of 30 MW or less may be an eligible renewable energy resource only if a retail seller owned or procured the electricity from the facility as of December 31, 2005. A new small hydro facility is not an eligible renewable energy resource for purposes of the RPS if it will require a new or increased appropriation or diversion of water from a watercourse. Pursuant to Public Resources Code Section 25743, Subdivision (b)(3)(C), a new small hydro facility must not require a new or increased appropriation of water under Part 2 (commencing with Section 1200) of Division 2 of the Water Code to be eligible for supplemental energy payments.

A small hydroelectric facility may exceed 30 megawatts if it is the result of efficiency improvements made to the facility after January 1, 2003, and the efficiency improvements do not require a new or increased appropriation or diversion of water from a watercourse. In addition, a small hydroelectric facility may exceed 30 megawatts if a portion of the facility is considered a separate conduit hydroelectric facility.

Solar thermal electric - the conversion of sunlight to heat and its concentration and use to power a generator to produce electricity.

Solid-fuel biomass - a biomass technology that uses solid fuel, such wood, agricultural waste, and other organic material that may be burned to produce electricity.

Wind power - energy from wind converted into mechanical energy and then electricity.

Glossary Source: CA Energy Commission--

Useful Links


Distributed Generation

Fuel Cells




CA Renewable Energy Program

CA Emerging Renewable Energy Program

Clean Energy Information Center