Other
Warm Air: Central Air Conditioning
The operation of conventional air conditioners are described. Their parts and the refrigerant/heat exchange cycle is discussed. The use of alternative geothermal systems are explained.
NASA
Climate Kids: 10 Interesting Things About Energy
Discover 10 very interesting things about energy, including conservation, fossil fuels, daylight savings time, hydropower, wind energy, solar power, greenhouse gases and BTUs (British Thermal Units).