Energy of the 21st Century

Scientists are researching new forms of energy that will help power the world in the 21^st century and reduce our dependence on non-renewable forms of energy.

10. Antimatter

Antimatter is the twin of matter. It is 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.

Antimatter is already in use in a medical imaging technique known as positron-emission tomography (PET), but its use as a potential fuel source is still in the realm of science fiction.

The problem of antimatter is its cost and that it can only be produced in small amounts in laboratories, but the cost of antimatter is predicted to decrease in the future as we will have the technology to produce and contain it.

9. Fuel Cells

At first glance, hydrogen fuel cells that may seem like the perfect alternative fuel source. They can generate electricity using only hydrogen and oxygen, and are pollution free.

Unfortunately, while hydrogen is the most abundant element in the universe, most of it is bound up to water. This means that pure unbound hydrogen must be produced with the help of other fuel sources which, in many cases, involve fossil fuels. Fuel sources negate many of the environmental benefits of hydrogen.

Another problem with hydrogen is that it cannot be compressed easily or safely, and it requires large tanks to store. Also, for reasons that are not fully understood, hydrogen atoms have a tendency to bleed through the materials holding them, thus weakening their containers.

8. Nuclear

Nuclear Fission releases harmful radiation and produces large amounts of radioactive material which can remain active for thousands of years and destroy entire ecosystems if leaked.

Currently, most nuclear power plants use fission, as fusion requires tremendous amounts of energy to produce and maintain necessarily high temperatures. But a natural phenomenon known as sonoluminescence might one day provide means of duplicating the power of the stars.

7. Ocean Thermal Energy Conversion (OTEC)

The oceans cover 70% of the earth, and water is a natural solar energy collector. OTEC 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 with cold seawater and turned into usable fresh water.

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.

6. Hydroelectricity

Hydropower supplies 20% 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 hydroelectricity dams can produce significant amounts of carbon dioxide and methane. Another drawback of dams is that people often need to be relocated, such in the case of the Three Gorges Dam Project in China.

5. Biomass

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.

4. Petroleum

Some call it Black Gold. Whole empires are based on it; wars have been fought over it. One reason that petroleum is so valuable is because it can be transformed into a variety of products, everything from kerosene to plastic and asphalt. Whether it’s a source for the future is hotly debated.

Estimates of how much petroleum is left in the earth vary wildly. Some scientists predict that petroleum reserves will reach a peak then rapidly decline as early as 2005; others believe that enough new reserves will be discovered to meet global energy needs for several more decades.

3. Wind

Taking the concept of windmills one step further, 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% 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.

2. Coal

Coal was the fuel that powered industrial revolution and has plagued an increasingly larger role in meeting the world’s energy needs ever since. The major advantage of coal is that there is lots of it, enough to last the world for another 200-300 years at the current rates of consumption.

While its abundance makes it very economical, burning coal releases impurities like sulfur and nitrogen into the air which can combine with water in the atmosphere to form acid rain. Burning coal also produces large amounts of carbon dioxide, a gas that according to most climate scientists contribute to global warming. Major efforts are underway to find new ways of making coal burn cleaners and to recover waste coal, a formerly unusable byproduct of coal mining.

1.Solar

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.

-by Brendan Salazar