Thursday, April 10, 2008

Future Energy Sources

Fossil fuels were formed before and during the time of the dinosaurs - when plants and animals died. Their decomposed remains gradually changed over the years to form coal, oil and natural gas. Fossil fuels took millions of years to make. We are using up the fuels formed more than 65 million years ago. They can't be renewed; they can't be made again. We can save fossil fuels by conserving and finding ways to harness energy from seemingly "endless sources," like the sun and the wind.
We can't use fossil fuels forever as they are a non-renewable and finite resource. Some people suggest that we should start using hydrogen.
Hydrogen is a colorless, odorless gas that accounts for 75 percent of the entire universe's mass. Hydrogen is found on Earth only in combination with other elements such as oxygen, carbon and nitrogen. To use hydrogen, it must be separated from these other elements.
Today, hydrogen is used primarily in ammonia manufacturing, petroleum refining and synthesis of methanol. It's also used in some outerspace programs as fuel for the space shuttles, and in fuel cells that provide heat, electricity and drinking water for astronauts. Fuel cells are devices that directly convert hydrogen into electricity. In the future, hydrogen could be used to fuel vehicles and aircraft, and provide power for our homes and offices.
Hydrogen can be made from molecules called hydrocarbons by applying heat, a process known as "reforming" hydrogen. This process makes hydrogen from natural gas. An electrical current can also be used to separate water into its components of oxygen and hydrogen in a process called electrolysis. Some algae and bacteria, using sunlight as their energy source, give off hydrogen under certain conditions.
Hydrogen as a fuel is high in energy, yet a machine that burns pure hydrogen produces almost zero pollution. Liquid hydrogen has been used since the 1970s to propel rockets and the space shuttle into orbit. Hydrogen fuel cells power the shuttle's electrical systems, producing a clean by-product - pure water, which astronauts can drinks.
You can think of a fuel cell as a battery that is constantly replenished by adding fuel to it - it never loses its charge.
Fuel Cell Uses
Fuel cells are a promising technology for use as a source of heat and electricity in buildings, and as an electrical power source for vehicles.
Auto companies are working on building cars and trucks that use fuel cells. In a fuel cell vehicle, an electrochemical device converts hydrogen (stored on board) and oxygen from the air into electricity, to drive an electric motor and power the vehicle.
Although these applications would ideally run off pure hydrogen, in the near term they are likely to be fueled with natural gas, methanol or even gasoline. Reforming these fuels to create hydrogen will allow the use of much of our current energy infrastructure - gas stations, natural gas pipelines, etc. - while fuel cells are phased in.
In the future, hydrogen could also join electricity as an important energy carrier. An energy carrier stores, moves and delivers energy in a usable form to consumers.
Renewable energy sources, like the sun, can't produce energy all the time. The sun doesn't always shine. But hydrogen can store this energy until it is needed and can be transported to where it is needed.
Some experts think that hydrogen will form the basic energy infrastructure that will power future societies, replacing today's natural gas, oil, coal, and electricity infrastructures. They see a new "hydrogen economy" to replace our current "fossil fuel-based economy," although that vision probably won't happen until far in the future.
Solar Power Satellites
One suggestion for energy in the future is to put huge solar power satellites into orbit around the earth. They would collect solar energy from the sun, convert it to electricity and beam it to Earth as microwaves or some other form of transmission. The power would have no greenhouse gas emissions, but microwave beams might affect health adversely. And frequent rocket launches may harm the upper atmosphere. This idea may not be practical for another century; if at all.
Other Ideas
Some people have claimed they've invented a machine that will "save the planet." Others are convinced that there's a vast conspiracy by fossil fuel and / or nuclear power companies to stop such devices from getting to the public.
Some of these contraptions use theories called "Free Energy," "Over Unity" or "Zero-Point Energy." As a matter of fact, you can find all sorts of information about such devices on the Internet. Just plug in any of those words.
But none of these devices have ever been proven, either theoretically or physically. The "free energy" area is filled with con artists selling unintelligible information, often clouded with technical sounding jargon, and seeking people with money to develop their inventions or ideas.
As the old saying goes, "a fool and his money are soon parted."
Most of these devices are perpetual motion machines, which violate known laws of science. Even the U.S. Patent Office will not issue a patent for such devices. With energy and the universe (at least as we know it today), there's no such thing as a free lunch; or free energy. You can't get energy from nothing because of the fundamental laws of physics that energy cannot be created or destroyed.
What about matter and anti-matter? What about energy that they use on Star Trek and in other science fiction stories? The ideas are interesting, but they are still fiction. Though science fiction has a basis in some fact. Jules Verne wrote about traveling under the water more than a hundred years ago, and today we have submarines. He also wrote about going to the moon, and in 1969 humans first set foot on our closest neighbor in space.
So, while some ideas being used by writers are fiction... there could be some basis in fact. Who knows, someone might create a mater-antimatter energy system that could revolutionize the way we think about energy and our universe.


No comments: