According to the Energy Information Administration, the production facilities that in 2006 supplied the United States with 4,064,702,000 megawatts of electricity were mainly powered by coal (49%), natural gas (20%) and nuclear energy (19%). Clean, green and renewable sources lag far behind, with hydropower supplying 7% of U.S. electricity and renewable sources such as wind and solar only 2.4%. Although that balance has shifted slightly since those numbers were compiled, with wind power alone doubling in output capacity between 2005 and 2008, hydrocarbons continue to dominate the U.S. energy landscape.

<p>However, economically speaking, the major problem with the current method the U.S. uses to supply itself with power is not the generation system but rather the grid that transports it. For safety reasons, power production facilities are traditionally constructed at a distance from population centers, and the cost of connecting the two via high-voltage transmission lines is astronomical at best. When Texas recently formed plans to upgrade their grid system, channeling power from new windfarms in the Panhandle and West Texas to cities in the center and east of the state, they budgeted $1.5 million per mile for the lines and considered it reasonable. (There are a lot of miles in Texas, but at least that included the poles.)

<p><b>Small Generators</b>

<p>So if transmitting power is expensive, but large electrical generation facilities can’t be built near population centers, how about small ones? The burgeoning trend is for residences and businesses, particularly those in rural areas, to produce their own power through small wind or solar systems; however, rather than “going off the grid” in the classical manner, these small generators stay connected and feed any leftover power back to the grid.

<p>Under a system known as net metering, the meter runs backward when the small generator has power to spare and forward when clouds cluster and the wind dies. But an alternative system known as the feed-in tariff (FIT) requires the power company to actually purchase this electricity, meaning these small systems can pay for themselves and even earn a profit before they fall apart or become obsolete. After Germany initiated a FIT program in 1999, solar panels appeared on the roofs of Bavarian barns and small generation systems surged, now providing over 14% of German electricity.

<p>One problem is that, rather than spreading the initial capital costs across a large client base as the power company does, the family or business must eat it themselves. To address this, governments at all levels are increasingly providing incentives such as tax credits to make that investment more palatable. Back in Texas, for example, value added to real estate by the installation of a green generation system is exempt from property taxes, and businesses that manufacture, sell or install solar and wind energy products are exempt from corporate taxes entirely. And there’s no cap.

<p><a href=”http://www.dsireusa.org/index.cfm?EE=1&RE=1″ target=”_blank”>DSIRE</a>, the Database of State Incentives for Renewables & Efficiency, is a website maintained by the North Carolina State University’s Solar Center which provides lists of such incentives for all 50 states.

<p><b>Costs of Renewable Energy</b>

<p>Even with the transmission grid out of the picture, the cost of green generation remains a prohibitive factor. On average, despite a 5% rise in electricity prices in 2008 and another 10% expected in 2009, most U.S. customers, both residential and industrial, pay less than ten cents per kilowatt-hour for power or around a dollar per watt of generation capacity. This has come to be considered the “magic number” that green generation must meet or beat in order to compete, and for the most part, it’s just not there yet.

<p>Wind energy has come closest. The cost of wind generation varies inversely with the size of the turbine, and bigger, more efficient systems are currently very near that coveted level. Rural residential systems are hovering between $2 and $3 per watt. For rural areas with good wind resources, it’s become the small generation system of choice.

<p>Despite decades of research, solar energy remains expensive, and the classical photovoltaic system still costs $8 to $10 per watt installed, not counting the incentives. Solar shingles, a form of urban camouflage designed to pacify home owner associations, push the price up to $10 to $12 per watt but can be rolled into a mortgage like any other roof. However, thin film solar panels, which eliminate expensive silicon and instead use inkjet printers to distribute nanotechnological solar ink across almost any backing surface, have lowered the cost to around $2 per watt.