Text 4c. Hydrogen & Fuel Cells

Hydrogen is the most abundant element known to man, and the supply is virtually limitless. Hydrogen can be made from fresh or salt water by electrolysis, which uses electricity to split the water molecule into its elemental components of hydrogen and oxygen. Because hydrogen energy has long been considered the ultimate universal fuel source, it is no wonder scientists have been working on hydrogen energy cells for more than 150 years. The technology hasn't slipped by NASA either, where such fuel cells have supplied power in all manned space missions since Project Gemini in 1965. Fuel cells provide astronauts with heat, electricity, and drinking water.

Hydrogen fuel cells are making big headlines in the new millennium, but this technology has actually been around for a long time. Ever since the British physicist and judge Sir William Grove constructed a prototype fuel cell in 1839, researchers have been improving the system. Grove demonstrated that hydrogen and oxygen could be compelled to bind together to form water while, at the same time, producing an electric current. Later in the 19th century, a hydrogen-rich gas was extracted from coal and used in the gas lamps and heaters of European and American towns and cities. Known as "town gas," it consisted of 50% hydrogen and 50% carbon monoxide, and its distribution helped lay the foundation for the safe use of hydrogen as an energy source.

In 1932, Francis Bacon, a descendant of the famed English scientist and philosopher Sir Francis Bacon, developed the first modern fuel cell. The cell was later refined and upgraded until a five-kilowatt system was successfully demonstrated in 1952. A few years later, scientists and engineers involved in America's nascent space program were attracted to fuel cell technology because it was compact and lighter than any type of battery and infinitely less dangerous than any known nuclear application. NASA employs hydrogen fuel cells in all its modern efforts, such as the US Space Shuttle and Space Lab projects. Using hydrogen today for commercial energy production and transportation makes good economic, political, and environmental sense.

The real news is that hydrogen fuel cells are being designed that will replace gasoline and diesel to power your vehicle and your home, hospital, or community center. The advantages to the typical internal combustion engine are significant. Hydrogen fuel cells power vehicles cleanly and will dramatically reduce the health hazards and the billions of dollars of medical costs associated with conventional automobile exhaust. Additionally, fuel cells and the hydrogen that energizes them can be produced in the United States, as opposed to importing politically risky Persian Gulf oil.

Like electricity, hydrogen does not occur naturally in a usable form — it must be generated or produced by burning fossil fuels or other forms of energy. One way of obtaining hydrogen is by cracking a water molecule into the components hydrogen and oxygen. The hydrogen is then fed into a fuel cell, a battery-like device that generates DC current. It supplies electricity by combining hydrogen and oxygen electrochemically without combustion. Unlike a battery, however, a fuel cell does not run down or require lengthy recharging. It will produce electricity and heat as long as hydrogen and oxygen are supplied. The oxygen is typically derived from ambient air, but the hydrogen comes from a system called a reformer, which produces the gas by breaking down a fossil fuel. Reformers do release pollutants as they break down the hydrocarbons to release hydrogen. Fuel cells are basically electrochemical engines that produce electricity by harnessing the reaction of hydrogen and oxygen. The only byproducts of the cell itself are clean water and useful heat.

Researchers are optimistic that hydrogen-fuel technology will play a big part in our future energy needs. Burning hydrogen contributes nothing to the greenhouse effect, ozone depletion, or acid rain. A sustained solar-hydrogen economy will go a long way towards solving some of the world's energy and environmental problems. To achieve commercial success with future consumers, however, a fuel cell vehicle must have clear economic advantages over the internal combustion engine — just having negligible emissions won't be sufficient. No matter how virtuous the clean-burning hydrogen economy may seem to a world choking on polluted air and water, it will involve very large investments in new technology and equipment. No single energy source can slake the thirst of a world consuming about 77 million barrels of oil a day; but considering the hidden costs to our health and environment from fossil fuel use, the conversion to renewable hydrogen will ultimately seem like a real bargain.

Exercise 11. Make up 5 questions to the text and answer them in pairs.

СПИСОК ЛИТЕРАТУРЫ:

1. http://www.ecology.com/secret-world-of-energy/index.htm

2. http://www.eere.energy.gov/windandhydro/wind_dist_tech.html

3. http://www.altenergy.org/renewable/solar/solar.html

4. http://www.altenergy.org/renewable/wind/wind.html

5. http://www.altenergy.org/renewable/biomass/biomass.html

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