| Ga | See gallium. |
| Gaas | See gallium arsenide. |
| Gale | Winds that can be classified as |
| Gallium (Ga) | A chemical element, metallic in nature, used in making certain kinds of solar cells and semiconductor devices. |
| Gallium Arsenide (Gaas) | A crystalline, high-efficiency compound used to make certain types of solar cells and semiconductor material. |
| Gallon | A unit of volume. A U.S. gallon has 231 cubic inches or 3.785 liters. |
| Gas | Gaseous fuel (usually natural gas) that is burned to produce heat energy. The word also is used, colloquially, to refer to gasoline. |
| Gas Synthesis | A method producing synthetic gas from coal. Also called the FISCHER-TROPSCH PROCESS. |
| Gasohol | In the United States, gasohol (E10) refers to gasoline that contains 10 percent ethanol by volume. This term was used in the late 1970s and early 1980s but has been replaced in some areas of the country by terms such as E-10, Super Unleaded Plus Ethanol, or Unleaded Plus. |
| Gasoline | A light petroleum product obtained by refining oil, and used as motor vehicle fuel. |
| Gassing | Gaseous by-products when charging a battery, e.g. Hydrogen from a lead acid battery. |
| Gassing Current | The portion of charge current that goes into electrolytical production of hydrogen and oxygen from the electrolytic liquid. This current increases with increasing voltage and temperature. |
| Gearbox | A protective casing for a system of gears. |
| Gel-Type Battery | A Lead-Acid battery in which the electrolyte is immobilized in a gel. |
| General Lighting | Lighting designed to provide a substantially uniform level of illumination throughout an area, exclusive of any provision for special visual tasks or decorative effects. |
| Generating Plant | A location where certain fuels (coal, natural gas, or nuclear) or hydropower are converted to electrical power. |
| Generating Station | A power plant. |
| Generation Company (Genco) | A regulated or non-regulated entity (depending upon the industry structure) that operates and maintains existing generating plants. The Genco may own the generation plants or interact with the short term market on behalf of plant owners. In the context of restructuring the market for electricity, Genco is sometimes used to describe a specialized "marketer" for the generating plants formerly owned by a vertically-integrated utility. |
| Generation Dispatch And Control | Aggregating and dispatching (sending off to some location) generation from various generating facilities, providing backups and reliability services. Ancillary services include the provision of reactive power, frequency control, and load following.(Also see "Power Pool" and "Poolco" below.) |
| Generator | A device for converting mechanical energy to electrical energy. |
| Geothermal (Ground Source) Heat Pump | a space heating/cooling system which moves heat from and to the earth, as opposed to making heat using a fuel source. Geothermal heat pumps take advantage of the almost constant temperature just a few feet underground |
| Geothermal Element | an element of a county general plan consisting of a statement of geothermal development policies, including a diagram or diagrams and text setting forth objectives, principles, standards, and plan proposals, including a discussion of environmental damages and identification of sensitive environmental areas, including unique wildlife habitat, scenic, residential, and recreational areas, adopted pursuant to Section 65303 of the Government Code. GEOTHERMAL ENERGY |
| Geothermal Energy | can be used to generate electricity, heat water and heat and cool buildings. |
| Geothermal Gradient | The change in the earth’s temperature with depth. As one goes deeper, the earth becomes hotter. |
| Geothermal Heat Pump | A type of heat pump that uses the ground, ground water, or ponds as a heat source and heat sink, rather than outside air. Compare to HEAT PUMP. |
| Geothermal Phenomena | an observable event at the surface, whose occurrence is the result of the Earth’s internal heat; includes volcanoes, geysers, hot springs, mud pots and fumaroles. |
| Geothermal Power Plant | a facility which uses geothermal steam or heat to drive turbine-generators to produce electricity. Three different types make use of the various temperature ranges of geothermal resources |
| Geothermal Reservoir | a large volume of underground hot water and steam in porous and fractured hot rock. The hot water in geothermal reservoirs occupies only 2 to 5% of the volume of rock, but if the reservoir is large enough and hot enough, it can be a powerful source of energy. Geothermal reservoirs are sometimes overlain by a layer of impermeable rock. While geothermal reservoirs usually have surface manifestations such as hot springs or fumaroles, some do not. |
| Geothermal Resource | the natural heat, hot water, and steam within the Earth |
| Geothermal Steam | Steam drawn from deep within the earth. |
| Geothermal Water | water heated by the natural heat inside the Earth. |
| Geyser | a natural hot spring that sends up a fountain of water and steam into the air; some geysers "spout" at regular intervals and some are unpredictable. |
| Gigawatt | One billion watts. |
| Gigawatt (GW) | A measurement of power equal to a thousand million Watts. |
| Gigawatt-Hour (Gwh) | A measurement of energy. One Gigawatt-hour is equal to one Gigawatt being used for a period of one hour, or one Megawatt being used for 1000 hours. |
| Gin Pole | Either of two different types of devices used with wind generator towers. With a tilt-up tower, it describes the lever that helps tilt the tower up. With a fixed tower, it describes a temporary crane used to raise tower sections or the wind generator. |
| Glazing | A covering of transparent or translucent material (typically glass or plastic) used for admitting light. |
| Global Climate Change | Gradual changing of global climates due to buildup of carbon dioxide and other greenhouse gases in the earth’s atmosphere. Carbon dioxide produced by burning fossil fuels has reached levels greater than what can be absorbed by green plants and the seas. |
| Global Warming | A term used to describe the increase in average global temperatures due to the greenhouse effect. |
| Global Warming/ Greenhouse Effect |
the trapping of heat in the atmosphere. Incoming solar radiation goes through the atmosphere to the Earth’s surface, but outgoing radiation (heat) is absorbed by water vapor, carbon dioxide, and ozone in the atmosphere. At certain levels this is beneficial because it keeps the planet warm enough for life as we know it. However, an increase in the normal amount of carbon dioxide and other gases may contribute to a human-caused warming trend that could have serious effects on global climate, the global ecosystem, and food supplies. |
| Glycol (Propylene Glycol) | An antifreeze, heat transfer fluid that is circulated through closed loop solar hot water collectors. |
| Governing | Limiting the output of a device. In respect to small wind generators, governing normally happens through furling. |
| Governor | A device that assists in the control of the speed of the blade rotation. It can be built into the blades 😉 |
| Gpm | Gallons per minute. |
| Green Credit | Green credits are a new way to purchase renewable electric generation that divides the generation into two separate products the commodity energy and the renewable attributes. The green credit represents the renewable attributes of a single megawatt of renewable energy. |
| Green Power | A popular term for energy produced from renewable energy resources. |
| Greenfield | A site on which no prior wind resource has been identified. |
| Greenhouse Effect | The heating effect resulting from long wave radiation trapped by greenhouse gases that have been produced from natural and human sources. |
| Greenhouse Effect (Relating To Buildings) | The characteristic tendency of some transparent materials (such as glass) to transmit radiation with relatively short wavelengths (such as sunlight) and block radiation of longer wavelengths (such as heat). This tendency leads to a heat build-up within the space enclosed by such a material. |
| Greenhouse Gases | Gases such as water vapor, carbon dioxide, methane, and low-level ozone that are transparent to solar radiation, but opaque to long wave radiation. These gases contribute to the greenhouse effect. |
| Grid | An electrical utility distribution network. |
| Grid (Also “Power Grid” And “Utility Grid”) | A common term referring to an electricity transmission and distribution system. |
| Grid Lines | Metallic contacts fused to the surface of a solar cell to provide a low resistance path for electrons to flow out to the cell interconnect wires. |
| Grid-Connected | An energy producing system connected to the utility transmission grid. Also called Grid tied. |
| Grid-Connected System | A solar electric or photovoltaic (PV) system in which the PV array acts like a central generating plant, supplying power to the grid. |
| Grid-Interactive System | Same as grid-connected system. |
| Grid-Tie System | A renewable energy system that is connected to the utility grid, selling excess energy back to the utility. Also called a utility-interactive system. |
| Gross Area | The area of a surface including areas not belonging to that surface (such as windows and doors in a wall). |
| Gross National Product (Gnp) | The total market value of the goods and services produced by a nation before deduction or depreciation charges and other allowance for capital consumption and is widely used as a measure of economic activity. |
| Ground | A connection from an electrical circuit to the earth. |
| Ground Fault | Unwanted current path to ground. |
| Ground Loop | An undesirable feedback condition caused by two or more circuits sharing a common electrical line. |
| Ground Mount | A peice of equipment upon which solar or wind modules are mounted. |
| Ground Rod (Electrode) | A metal rod (typically 5/8 inch diameter) that is driven into the earth (typically 8 feet deep) and is electrically connected to the negative conductor and/or any metal parts, wiring enclosures, or conduit of an electrical circuit. |
| Gust | A sudden brief increase in the speed of the wind. |
| Guy Wires | Steel cables that support a tower. |
