A man named Charles Fritts is credited with inventing the very first solar cell back in the 1880s, just a few short years after Thomas Edison received a patent on his incandescent light bulb.

Covering every roof in Australia couldn't provide electricity for the entire planet, but it could supply Australia all the electricity it needed.

It takes less than four years for the green energy production of solar panels to cover for the energy it took to produce them. Solar panels continue to be useful for many years after that point.

Portions of the Great Wall of China dating back to 5,000 B.C. were built using rammed-earth construction.

The Environmental Protection Agency has a green infrastructure that reduces sewer runoff, improves air quality, and directs some runoff toward groundwater and drinking purification systems.

The "cool" in cool roof applies to temperatures; cool roofs excel at reflecting heat, which reduces the amount of energy required to cool and heat a building.

Electrochromic smart glass uses electrical charges to control how much light is absorbed or reflected. The ability to control the window's tint makes smart glass an ideal energy-saving material.

In 2009, 27 percent of Iceland's power came from geothermal energy, thanks to the warmth created by the area's volcanic activity.

Icelandic cities like Reykjavík pipe hot water under the pavement in winter to keep the roads from freezing over.

Using recycled material in the insulation manufacturing process actually requires less energy than converting raw materials, thus reducing the amount of work and resulting pollution.

Between 2006 and 2007, North American companies actually used nearly 3 billion pounds of recycled glass producing insulation.

The average fiberglass insulation is at least 50 percent recycled glass, while the average cellulose insulation is at least 80 percent recycled newspaper.

Some environmentally friendly biodegradable paints include milk protein, among other ingredients.

Smart meters are electrical meters that record energy consumption and can wirelessly transmit data to certain appliances within the home.

By communicating with a smart meter, GM's Brillion smart appliances can determine peak electricity rate times and schedule automatic processes to run at the cheapest times.

LG's Food Management technology allows you to program your refrigerator with the expiration dates of the foods you buy, but the refrigerator has no way of scanning food and deciding that it's gone bad.

Passive solar design is all about using the sun's energy effectively with no actual equipment -- building large windows along one side of the house to capture heat during the day, for example.

Straw-bale construction is real. Leftover straw packed into bales is often inserted into a wooden framework to create the walls and form insulation.

The "zero-energy building" has no net energy consumption; it uses green technologies to create its own renewable energy, resulting in no outside energy consumption and no emissions.

By percentage, smaller companies produce more of their total energy requirements through wind power, but the United States is the largest annual generator of wind, producing more than 70 Terawatt-hours in 2009.