CO2: Carbon dioxide. A colorless, odorless gas that is produced when a carbon-based fuel is burned. Carbon dioxide is a greenhouse gas - it lets light in, but traps heat. The increased amount of carbon dioxide produced by human activities has contributed to climate change.

compact fluorescent bulb: Properly referred to as a compact fluorescent lamp (CFL), it is an energy saving light that is replacing incandescent bulbs. The compact fluorescent uses much less power, and has a much longer life, than incandescent bulbs.

incandescent bulb: A light bulb that contains a filament which is heated until it glows and produces light. Incandescent bulbs have been the most common light bulb for many years.

hybrid vehicle: A vehicle that is powered by a gas-fueled engine and one or more electric motors. The electric motors draw their power from a battery, which is usually charged using excess energy from braking.

kilowatt (kW): One thousand watts. A measurement of electrical power.

kilowatt hour (kWh): A measurement of electrical energy generated or used. Equal to one kilowatt of power expended for an hour. Some typical examples:





Medium window-unit AC

1000 watts

1 hour

1 kWh


500 watts

24 hours

12 kWh

32" LCD television

100 watts

5 hours

0.5 kWh

Laptop computer

50 watts

40 hours

2 kWh

43" ceiling fan at low speed

24 watts

10 hours

0.24 kWh

kWh: (see kilowatt hour)

LED: Light-emitting diode. LED lights have many advantages over standard incandescent light bulbs, including lower energy consumption and a longer life-span.

metric ton: Equivalent to 2205 pounds.

MMBTU: BTU is British Thermal Unit, which measures heat generated. MMBTU is one million BTUs, and is often used in comparing fossil fuel and electrical energy.

MWh: Megawatt hour. A megawatt is a million watts.

passive solar: Non-electric, non-mechanical processes for using solar energy. Sunlight heating a room through a window is one example of a passive solar process.

photovoltaic: A process for generating electricity from sunlight, commonly used in solar panels.

plug-in hybrid vehicle: A hybrid vehicle whose battery is recharged by plugging it into the electric power grid.

solar thermal: A process for collecting solar energy and using it for thermal (heat) energy. Solar thermal collectors are generally simpler than solar electric panels, and make more efficient use of solar energy.

watt: An energy measurement. As an example, a 60-watt incandescent light bulb consumes 60 watts of energy when it's operating.