MagazineJanuary 2008RENEWABLE Energy 101

RENEWABLE Energy 101

THE Solar Solution

Simply put, solar is the answer. We already have the technology to build a sustainable solar-electric economy that can end our addiciton to fossil fuels, stabilize the climate, and maintain our standard of living.

Direct solar radiation provides 350 million terrawatt hours of energy. In contrast, the combined total of all the world’s coal, oil, natural gas, uranium, and tar sands is 11 million terrawatt hours. Solar can provide 30 times more energy than all nonrenewable sources combined.

Solar produces no greenhouse gases, so it has the potential to drastically reduce our contributions to global warming. Solar power is also readily available. Virtually all areas of the U.S. can produce cost-effective solar electricity, and solar power generators can be located in densely populated areas that currently use the most electricity, making its energy transmission far more efficient than any other source.

The cost of solar power has been declining steadily for the last two decades. Currently, solar power costs twice as much as conventional electricity (compared to 50 times as much 20 years ago). Experts say solar power will be cost competitive within 15 years—or sooner if oil subsidies are replaced with investments in the solar industry.

So why hasn’t solar been more widely embraced? As Ralph Nader puts it, “The use of solar energy has not been opened up because the oil industry does not own the sun.”


Answers in the Wind

Wind power is the fastest growing energy source in the world, particularly here in the U.S. Wind turbines emit no atmospheric emissions and no greenhouse gases, and it’s one of the lowest-priced renewable energy technologies available today.

Only six percent of the United States’ land mass qualifies as “good wind areas,” but that six percent has the potential to supply one and a half times the current electricity consumption of the entire United States population, according to the Department of Energy.

Most turbines can be placed on farms in rural areas, which is where a majority of the best wind sites are found. Farmers could continue to work their land and could even charge rent to the wind power companies.

However, wind is intermittent, and the energy produced from turbines can’t be stored without batteries. Wind power also requires a higher initial investment than fossil-fuel generators, and there are still lingering environmental concerns regarding bat and bird populations. One of the biggest obstacles wind power faces, however, is aesthetics. Wind farms have been stalled in the Appalachians because some people find the turbines unattractive along mountain ridge lines.


Ethanol: Don’t Believe the Hype

When a presidential candidate says “alternative energy,” most of the time they mean corn-based ethanol. The biofuel is being touted by politicians as the ticket to oil independence. Corn-based ethanol plays a large part in President Bush’s new energy plan as well as most energy legislation being considered in both the Senate and the House. And virtually all of the presidential candidates support corn ethanol. But the production of corn-based ethanol requires more energy than it actually provides, and it actually increases greenhouse gas emissions.

Producing corn-based ethanol requires 29% more energy than it actually provides—giving ethanol a net energy balance of zero or worse, says Cornell University professor David Pimentell, who has been studying ethanol for over twenty years. And while corn-based ethanol burns cleaner than gas inside a vehicle’s engine, it is actually a dirtier fuel than gas over the entire life cycle of the fuel. Corn ethanol is made by mashing corn into a thick soup, which is then placed into high temperature fermenters that break the soup down into ethanol and water. The product is then boiled and condensed to squeeze the water out. The majority of those energy-intensive corn ethanol plants are powered by either coal or natural gas. And since ethanol cannot be transported in gas pipelines, it has to be moved in trucks, which further degrades its energy balance.

Ethanol is also heavily subsidized. Thanks to the 2005 Energy Bill, a vast majority of those subsidies ($3 billion in 2006 alone) go directly to the big oil companies who blend ethanol into their gasoline. Corn itself is the most heavily subsidized crop in the U.S. The fuel would not ever be economically viable without these subsidies. 

Diverting more corn to fuel production has already caused corn prices to double on the global scale, affecting the welfare of third world countries that depend on corn as a primary source of food for humans and livestock.

Even though the reality of ethanol doesn’t live up to its hype, politicians from both parties become enthusiastic ethanol supporters when they run for president. Why? Iowa. Iowa is America’s largest producer of ethanol, producing 3,286 million gallons of ethanol per year, with 28 ethanol plants operating within their borders. It’s the heart of the “Corn Belt,” and it’s a swing state whose caucus kicks off the presidential election.


THE Silver Lining—Cellulosic Ethanol

While corn is the only kind of ethanol currently being produced in the U.S., many environmental organizations are excited about the prospect of cellulosic ethanol. Cellulose is more difficult to convert into ethanol, but as the main component of all plant cell walls, it’s the most common organic compound on earth, and it contains more net energy and results in lower greenhouse gas emissions than corn-based ethanol. Using cellulose to make ethanol also opens up the possibility of using waste (corn stalks, rice straw, wheat straw, wood chips, and grass) to make transportation fuel. According to the National Resources Defense Council, we could eventually produce as much as 150 billion gallons of cellulosic ethanol by 2050 (two thirds the current gas consumption in the U.S.).

Currently, cellulosic ethanol is only in the demonstration phase, but it’s proving to be a cleaner, more efficient fuel over its entire life cycle. Cellulosic ethanol has a 15 to 1 energy balance. An acre of switchgrass could produce twice as many gallons of ethanol as an acre of corn because the whole plant could be used as opposed to just the grain. Production of cellulosic ethanol from switchgrass requires less water, less fertilizer, less pesticides, less herbicides, less diesel gas, and is accompanied by less erosion. Overall, harvesting switchgrass for ethanol requires very little energy and saves on raw materials since you could use the waste products of food that is already being grown, making cellulosic ethanol a more promising “fuel of the future” than corn ethanol.

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