Steam rising from a geothermal power plant in Iceland.Photo: Wikipedia CommonsThe heat in the upper six miles of the Earth's crust contains 50,000 times as much energy as found in all the world's oil and gas reserves combined. Despite this abundance, only 10,700 megawatts of geothermal electricity generating capacity have been harnessed worldwide. Partly because of the dominance of the oil, gas, and coal industries, which have been providing cheap fuel by omitting the costs of climate change and air pollution from fuel prices, relatively little has been invested in developing the Earth's geothermal heat resources. Over the last decade, …

A new energy economy is on the horizon.Photo courtesy Kevin Dooley via FlickrAs fossil fuel prices rise, as oil insecurity deepens, and as concerns about climate change cast a shadow over the future of coal, a new energy economy is emerging. The old energy economy, fueled by oil, coal, and natural gas, is being replaced by one powered by wind, solar, and geothermal energy. Despite the global economic crisis, this energy transition is moving at a pace and on a scale that we could not have imagined even two years ago. And it is a worldwide phenomenon. Consider Texas. Long …

Around midnight on Wednesday, August 11th, a group of commodity analysts will gather at a meeting site in the massive South Building of the U.S. Department of Agriculture (USDA) in Washington, D.C. Once they are assembled, the door will be locked. Cell phones will be collected. Phone and Internet lines will be disconnected. Short of a medical emergency, no one will be permitted to leave before 8:30 am. USDA produces an estimate of world grain production, consumption, and trade by the 12th of each month. The gathered analysts will consult reports from a worldwide network of agricultural attachés, satellite images …

Kick old, energy-inefficient refrigerators to the curb -- and curb your energy costs and carbon emissions too. There are enormous opportunities to use energy more efficiently. Investing in energy efficiency is often far cheaper than expanding the energy supply to meet growing demand. Efficiency investments typically yield a high rate of return, saving consumers money, and can help fight climate change by avoiding carbon dioxide (CO2) emissions from burning additional fossil fuels. Just as compact fluorescent lamps (CFLs) offer great electricity savings over incandescent light bulbs, a similar range of efficiencies is available for many household appliances, such as refrigerators …

A dangerous geopolitics of food scarcity is emerging in which individual countries, acting in their narrowly defined self-interest, reinforce the trends causing global food security to deteriorate. This began in late 2007 when wheat-exporting countries, like Russia and Argentina, attempted to counter domestic food price rises by limiting or banning exports. Viet Nam banned rice exports for several months, and several other minor exporters also restricted exports. While these moves reassured those living in the exporting countries, they created panic in the scores of countries that import grain. At that point, as world market prices for grain and soybeans were …

The bicycle has many attractions as a form of personal transportation. It alleviates congestion, lowers air pollution, reduces obesity, increases physical fitness, does not emit climate-disrupting carbon dioxide, and is priced within the reach of the billions of people who cannot afford a car. Bicycles increase mobility while reducing congestion and the area of land paved over. Six bicycles can typically fit into the road space used by one car. For parking, the advantage is even greater, with 20 bicycles occupying the space required to park a car. Few methods of reducing carbon emissions are as effective as substituting a …

The 21st century began on an inspiring note: The United Nations set a goal of reducing the share of the world’s population living in extreme poverty by half by 2015. By early 2007, the world looked to be on track to meet this goal, but as the economic crisis unfolds and the outlook darkens, the world will have to intensify its poverty reduction effort. Among countries, China is the big success story in reducing poverty. The number of Chinese living in extreme poverty dropped from 685 million in 1990 to 213 million in 2007. With little growth in its population, …

Drip irrigation is a simple and easy way to reduce water use.Photo courtesy of photofarmer via flickr With water shortages constraining food production growth, the world needs an effort to raise water productivity similar to the one that nearly tripled land productivity over the last half-century. Since it takes 1,000 tons of water to produce 1 ton of grain, it is not surprising that 70 percent of world water use is devoted to irrigation. Thus, raising irrigation efficiency is central to raising water productivity overall. Data on the efficiency of surface of water projects -- that is, dams that deliver …

The lightCompact fluorescent light bulbs -- what a bright idea.ing sector is on the edge of a spectacular revolution, a shift from the century-old, inefficient incandescent light bulb to far more efficient technologies. Perhaps the quickest, most profitable way to reduce electricity use worldwide -- thus cutting carbon emissions -- is simply to change light bulbs. The first advance in this field came with compact fluorescent lamps (CFLs). Replacing old-fashioned inefficient incandescent bulbs that are still widely used today with new CFLs can reduce the electricity used for lighting by three fourths. Over its lifetime, each standard (13 watt) CFL …

At a time when excessive pressures on the earth’s land and water resources are of growing concern, there is a massive new demand emerging for cropland to produce fuel for cars—one that threatens world food security. Although this situation had been developing for a few decades, it was not until Hurricane Katrina in 2005, when oil prices jumped above $60 a barrel and U.S. gasoline prices climbed to $3 a gallon, that the situation came into focus. Suddenly investments in U.S. corn-based ethanol distilleries became hugely profitable, unleashing an investment frenzy that will convert one fourth of the 2009 U.S. …