Biomass is plant material (e.g. cornstalks, firewood) and animal wastes (e.g. manure) that can be used as a fuel.

Geothermal heat is heat generated by the interior of the earth. Volcanoes and hot springs are examples of releases of geothermal heat.

Most objects release heat in the form of infrared light. There are special cameras that can detect this light and make a photograph showing the heat leaving the object.

The electricity infrastructure is comprised of the power plants, power lines, and utility companies that provide electricity to anyone who needs it.

Liquid crystal displays (LCD) are used in a variety of digital equipment, from watches to laptop computers. LCDs use liquid crystals to change the reflectivity in an applied electric field.

A watt is a unit of electric power. For example, a simple light bulb may use 75 watts of electricity. A watt-hour is a measurement of how much electricity is used in an hour. In one hour, this light bulb would use 75 watt-hours of electricity. A Megawatt-hour (MWh) is 1,000,000 watts-hours. 13,333 of the 75 watt bulbs would use 1 MWh in one hour.

Peak load times are times in the day when most of the electricity is used in a home, such as the mornings when many people are taking showers and preparing for the day. This activity increases the electricity demand on the utility companies, who need to supply more power.

Photovoltaic cells are devices that are able to convert solar energy to electrical energy.

Most objects release heat in the form of infrared light. There are special cameras that can detect this light and make a photograph showing the heat leaving the object.