Wind energy is currently on the rise in the US as prices have dropped from .40 cents per kilowatt-hour in the ‘80s to .04-.05 cents presently, on par with coal. It is_currently the fastest growing renewable energy source in the world, with 6000 megawatts of energy (enough to power 1.5 million US homes) coming online every year.
Ridgelines in sustained wind regions, such as Vermont and New Hampshire, as well as large parts of the Great Plains (N. Dakota has huge potential) hold the greatest potential for future wind farms. Opposition to wind farms is mainly an aesthetic argument; however turbines placed in the path of bird migrations have been known to be detrimental to nesting and migration. For more information on wind check out: telosnet.com/wind/index.htm.
The collection of solar energy comes through both active and passive systems. Passive systems can be as simple as a double-paned, south-facing (for our hemisphere) sun room filled with barrels of water painted black. This sun room would have vents allowing heat that came from the sun at the cost of zero emissions to be exchanged with the house. Depending on sunlight received and insulation quality, homes with passive solar systems can save up to 50% in heating costs. Currently about 7% of new homes are equipped with passive solar systems like the one described above. Passive measures are highly effective, relatively cheap, and easy to implement. Better education in these methods could further spread their use.
Active solar energy is similar to passive solar energy, except that water, oil, or something else that requires heating is pumped past the solar catchment area to facilitate heating. In a house, this would mean piping water for the house through a windowed solar catchment before putting it into the water heater, raising the temperature substantially by renewable methods before heating it with oil or natural gas.
The most commonly known source of solar energy, however, is the photovoltaic (PV) cell. Photovoltaic cells convert solar energy into electricity, and they can be installed on roofs or other areas with good solar access. Contrary to popular belief, they work even on cloudy days, but at a diminished capacity (about 80 percent). Currently PV technology is expensive at 15 cents per kilowatt-hour and it is only economical for use in sunny rural areas where the cost of extending power lines would exceed PV costs.
Whether in the form of methanol, wood products, or vegetable oil, biomass represents a renewable fuel source that deserves serious consideration as a possible alternative to the fossil fuels used in both power generation and transportation. Because biomass products sequester carbon from the atmosphere to grow, the net carbon effect of burning them is neutral.
One issue in using biomass is the fact that to grow, harvest and fertilize the plants requires methods that currently use fossil fuels that release greenhouse gases. Also, up to 30-40% of potential energy can be lost in the process of converting corn, for example, to ethanol. Despite these issues biomass is being employed in many mass transit systems, including Denver, Colorado, because of its reduced emission of CO2 and SO2.