Energy Sources Right Under Our Noses
By James Donahue
The April edition of
Common Ground offers an interesting article by Alastair Bland that outlines four “far-out renewable energy technologies”
that are not only feasible, but already in the works to be future sources of heat, lights and power.
Reaching beyond the most
common sources including wind, solar, ocean currents, flowing rivers and making ethanol from plants, Bland takes his readers
into new and somewhat thought-provoking places. They include methane gas from sewage plants, and livestock feedlots; gasification
of landfill trash, converting algae into oil and capturing hydrogen from thin air.
Among the most exciting
concepts revealed by the article is converting algae into biofuel. It seems that algae cells form, mature and divide within
hours, thus making it an extremely fast-growing life form that lives on the carbon dioxide and hydrogen that exists in the
air. Its presence helps clean the air of carbon dioxide.
Even more exciting is
that a single acre of land converted to ponds for algae production can produce from 5,000 to 10,000 gallons of oil each year.
By comparison that acre used for soybean production would only produce from 50 to 100 gallons of biofuel. It is estimated
that less than 10 percent of America’s cropland would be needed to grow enough algae
to supply liquid fuel needs for the entire nation.
It seems that those tiny
one-celled organisms can consist of 50 percent vegetable oil. This oil can be processed for either diesel or jet fuel.
The snag in fuel from
algae is the high production cost. But some 30 companies in the world are working on this problem. Researchers say algae biofuel
may be on the market within the next two years.
The concept of using
methane gas for fuel has already been tried successfully on some large cattle farms, and researchers are looking into ways
to capture methane, a natural by-product of human and animal waste, from all the right places. Not only are they targeting
livestock farms, but metropolitan landfills.
The capture of methane
will not only provide a natural fuel source, but it will help ease the problem of global warming, since all of this untapped
methane is presently spewing out into the atmosphere and contributing to the heating of our planet.
Researchers say raw sewage
can be pumped through sealed chambers called anaerobic digesters. Inside these digesters, particular microbes consume the
material and convert it to methane at an estimated rate of six cubic feet of gas per pound of dry material. Thus a 3,000 head
dairy farm can produce enough energy to keep 60 average sized three-bedroom homes powered for a year.
Yet another bane on our
landscape has been the garbage and trash dumps, or landfills as they are known today. This amounts to millions of tons of
unwanted municipal solid waste, and because we are a throw-away society, and insist on wrapping everything we buy in plastic
and/or paper, the piles are getting bigger with each passing year. But there is energy in them thar landfills and the technology
to capture it is also just around the corner.
The solution to the landfill
mess has been tried by some major cities in large burners, but they proved costly to operate and required a lot of refuse
before they could be used effectively. Yet this process can be intensified, with the burners operating at a temperature on
par with the sun’s surface. Heat like that breaks up the material’s molecular structure, converting it into pure
hydrogen and carbon monoxide, which can be converted into synthetic gas that is a building block for a variety of liquid fuels.
This process, called
gasification, burns everything so completely there are no waste emissions. All of the energy is converted into hydrogen and
While there are still
some bugs to be worked out in the gasification process, Japan fired up the first successful plant like this in 2002 and it
is processing over 200 tons of solid waste daily. An even larger gasification plant is planned for St. Lucie County, Florida,
which is expected to be operating by 2010.
The final idea . . .
making fuel from the natural gas that exists in the air . . . is technically possible but so far impractical because of the
high cost of doing it. The process is complex and involve specialized electrochemical processing cells that use heat, cooling
towers, and a lot of technical tricks that separate hydrogen from oxygen.
The process demands great
volumes of air and extreme heat, making it somewhat impractical. Yet technicians are working on this problem, and may someday
have a solution.