What are alternative ways of getting energy?

Answer 1

1. POO POWER

Yes, we're serious. Poop produces methane, which is not only a greenhouse gas, but can be harnessed and used for viable renewable energy. While the technology and processes are still being refined, it's not unlikely that cow manure will be the new solar panel in the coming years. Dogs and even human waste might eventually join the poo parade as well.

2. SOUND ENERGY

While there isn't a residential prototype for this technology built yet, the idea that soundwaves could be transformed into usable energy is not only promising, but mind-blowing. University of Utah Physicist Orest Symko and his students have developed a way to turn excess heat into sound and finally into electricity, and we can't wait to see this technology applied to home energy.

3. HUMAN MOTION

We've seen this technology used in the Sustainable Dance Club as well as in Hong Kong's human-powered gyms, and the principle could easily be applied to residences as well. When we humans walk, dance, work out, run, move, we create energy. Through new technology, this energy can be harnessed into usable energy to cycle back into our buildings, dance clubs, gyms, and homes. Its only a matter of time before the Sustainable Dance Club concept comes makes inroads into the home.

4. WIND-KINETICS

Going way beyond a simple wind turbine, Michael Jantzen's Wind Shaped Pavilion turns architecture into renewable energy source. The kinetic wind house is a large fabric structure that rotates in segments around a central support frame, generating enough electricity as it moves to light the pavilion at night. This concept takes wind power to a whole new level.

5. SPINACH (i.e photosynthesis)

Not just full of nutrients for your body, spinach also has the potential to nourish your house. The winning entry from the Cradle to Cradle House competition proposed an amazing solar energy harvesting system based on photosynthesis, using a solar cell system whose main component for generating electricity is a protein called Photosystem I, which is derived from spinach. If things go according to plan, construction on a giant solar tower could begin in Australia in 2006. The 3,280-foot tall tower will be surrounded by a vast greenhouse that will heat air to drive turbines around the base of the tower. It is estimated that the power station will be able to generate 200 megawatts of electricity, enough to power 200,000 households. Solar energy requires no additional fuel to run and is pollution free. Sunlight can be captured as usable heat or converted into electricity using solar, or photoelectric, cells or through synchronized mirrors known as heliostats that track the sun's movement across the sky. Scientists have also developed methods for using solar power to replace a gas-powered engine by heating hydrogen gas in a tank, which expands to drive pistons and power a generator. Drawbacks of solar energy include high initial cost, and the need for large spaces. Also, for most solar energy alternatives, productivity is subject to the whims of air pollution and weather, which can block sunlight. Taking the concept of windmills one step further, or higher, scientists want to create power stations in the sky by floating windmills 15,000-feet in the air. The strange crafts will be kept afloat by four propellers that double as turbines, and feed electricity back to earth through a cable. Wind energy currently accounts for only 0.1 percent of the world's electricity demands, but that number is expected to increase as wind is one of the cleanest forms of energy and can generate power as long as the wind blows. The problem, of course, is that winds don't always blow, and wind power cannot be relied upon to produce constant electricity. There is also concern that wind farms could impact local weather in ways that are yet to be fully understood. Scientists hope that taking windmills to the skies will solve these problems, since winds blow much stronger and more consistently at high altitudes. Biomass energy, or biofuel, involves releasing the chemical energy stored in organic matter such as wood, crops, and animal waste. These materials are burned directly to produce heat or refined to create alcoholic fuels like ethanol. But unlike some other renewable energy sources, biomass energy is not clean, since burning organic matter produces large amounts of carbon dioxide. It may be possible, however, to offset or eliminate this difference by planting fast growing trees and grasses as fuel supplies. Scientists are also experimenting with using bacteria to break down biomass and produce hydrogen for use as fuel. One exciting but controversial biofuel alternative involves a process known as thermal conversion, or TCP. Unlike conventional biofuels, TCP can convert practically any type of organic matter into high quality petroleum with water as the only byproduct, proponents claim. It remains to be seen, however, whether Changing World Technologies, the company that patented the process, can produce enough oil for it to become a viable fuel alternative. Whether falling, flowing, or otherwise moving in tides or under-ocean currents, water can be harnessed to produce electric power. Hydropower supplies approximately 20 percent of the world's electricity. Until recently, it was generally believed that water energy is an abundant natural resource that requires no additional fuel and produces no pollution. Recent studies, however, challenge some of these claims and suggest that hydroelectric dams can produce significant amounts of carbon dioxide and methane through the decay of submerged plant material. In some cases, these emissions rival that of power plants running on fossil fuel. Another drawback of dams is that people often need to be relocated. In the case of the Three Gorges Dams Project in China -- which will be the largest dam in the world when completed in 2009 -- 1.9 million people were moved and countless historical sites were flooded and lost. Oceans cover 70 percent of the Earth, and water is a natural solar energy collector. OTEC, or ocean thermal energy conversion, aims to exploit this fact and use the temperature differences between surface water heated by the sun and water in the ocean's chilly depths to generate electricity. OTEC plants generally fall into three categories: Closed Cycle: A liquid with a low boiling point like ammonia is boiled using warm seawater. The resulting steam is used to operate an electricity-generating turbine; the vapor is then cooled using cold seawater.

Open Cycle: Similar to the closed cycle OTEC, except there is no intermediate liquid. The warm seawater is converted into low-pressure vapor that is used to generate electricity. The vapor is then cooled and turned into usable fresh water with cold seawater.

Hybrid Cycle: A closed cycle OTEC is used to generate electricity, which is then used to create the low-pressure environment necessary for the open cycle. OTEC plants can double as fresh water sources and the nutrient rich seawater drawn from ocean depths can be used to culture marine organisms and plants. The major drawback of OTEC is that since they operate on such small temperature differences, generally about 36 degrees Fahrenheit (20 Celsius), they are only 1 to 3 percent efficient. At first glance, hydrogen fuel cells might seem like the perfect alternative to fossil fuels. They can generate electricity using only hydrogen and oxygen and are pollution free. An automobile running on hydrogen fuel cells would not only be more efficient than one powered by an internal combustion engine, its only emission would be water. Unfortunately, while hydrogen is the most abundant element in the universe, most of it is bound up in molecules such as water. That means pure unbound hydrogen must be produced with the help of other energy sources -- which in many cases involve fossil fuels. If that's the case, then many of the environmental benefits of hydrogen as a fuel are negated. Another problem with hydrogen is that it cannot be compressed easily or safely, and requires large tanks to store. Also, for reasons that are not fully understood, hydrogen atoms have a tendency to bleed through the materials encasing them, thus weakening their containers. Honda introduced last year a scooter that uses fuel cell technology. Antimatter is the Bizarro twin of matter, made up of antiparticles that have the same mass as ordinary matter but with opposite atomic properties known as spin and charge. When the opposed particles meet, they annihilate each other and release tremendous amounts of energy as dictated by Einstein's famous equation, E=mc2. Antimatter is already in use in a medical imaging technique known as positron emission tomography (PET), but its use as a potential fuel source remains in the realm of Science Fiction. The problem with antimatter is that there is very little of it in the universe. It can be produced in laboratories, but currently only in very tiny amounts, and at prohibitively high costs. And even if the problem of production could be solved, there is still the knotty question of how to store something that has a tendency to annihilate itself on contact with ordinary matter, and also how to harness that energy once created. NASA funds research into creating antimatter drives that could one day take humanity to the stars, but dreams of antimatter-powered starships as seen on Star Trek are still a long way off, all experts agree.