In a world obsessed with finding alternative energies to replace fossil fuels, researchers are convinced the future lies with solar, wind and nuclear technologies.
However, other sources, including the moon, the oceans and even leftovers from restaurants could provide the alternative energy we need to power the Earth for centuries to come.
A possible renewable energy source can be found all over the world in restaurants, homes, and garbage. At a new UC Davis facility, researchers have created technology that enables the production of energy by processing leftover food.
Called the Biomass Energy Project, the facility, run by UC Davis professor of agricultural and biological engineering Ruihong Zhang, will take as much as eight tons of leftovers daily from Bay Area restaurants. This will be enough to power 10 California homes for a day, according to the UC Davis College of Agricultural and Environmental Sciences website.
Unlike other digesting technology, Zhang’s “anaerobic phased solids digester” can digest a wider variety of wastes. It works twice as fast as other digesters to convert the food into energy. It also produces two clean gases, hydrogen and methane, that can be burned to produce electricity.
“This technology will make a substantial dent in both our landfill needs and our use of petroleum and coal for fuels and electricity,” Zhang said on the A&ES website. “It also will reduce our greenhouse gas emissions.“
It is also possible to generate electricity from the moon by capitalizing on the tides created by the gravitational pull the moon has on Earth’s oceans, according to howstuffworks.com.
Although the sun exerts more gravitational force than the moon, the moon exerts almost twice as much gravitational force on Earth than the sun. This is because the moon is only 239,000 miles away, compared to the 93 million miles that separate the Sun and the Earth. Proximity is more important than size in regard to gravity, according to the Office of Naval Research’s website.
The moon’s gravitational pull on the oceans creates predictable tides on Earth. Scientists can use this to their advantage by placing underwater turbines into the oceans.
As the tides move, they create kinetic energy and the underwater turbines act like windmills in water. The underwater current spins the turbine’s blades, which are attached to a gear box and connected to an electrical generator. The electricity generated transfers via cables onto the shore, and is then transferred to wherever electricity is needed.
Underwater turbines have a few advantages over land windmills. At this time, the use of land windmills has become a problem because of the scarcity of available land.
In addition, since water is denser than air, it requires less energy to spin an underwater turbine than a windmill, making it more efficient. Tides are also predictable, whereas the kinetic energy of wind is not.
Tidal energy has its drawbacks, as well. The environmental impacts that these turbines may have on the surrounding ecosystems is not known. In shallower waters, the turbines may be exposed, causing a potential impact on commercial shipping, according to the OCS Alternative Energy and Alternate Use Programmatic EIS website.
The moon itself could be used as an energy source. Helium 3, an isotope of helium, is deposited on the moon’s surface by solar wind, charged particles given off by the sun, according to an article on ezinearticles.com.
Helium 3, if used in a fusion reactor with deuterium, releases a gas that is very efficient and releases few radioactive byproducts. There is very little on the Earth because of the ozone layer, which prevents the solar wind from depositing radioactive byproducts in the soil.
However, since the moon does not have an ozone layer to protect it, experts estimate there are 1 million tons of radioactive byproducts on the moon. If a spacecraft brought back 25 tons of Helium 3, it would be enough to power the United States for a year, according to ezinearticles.com.
Although it has huge potential, the possibility of harvesting and creating fusion reactors is fiscally impossible. It would require a large donation of money to set up a base on the moon and conduct scientific research. It would also take nearly 10 to 15 years before any sign of progress would be made.
“This approach is scientifically interesting, but economically irresponsible,” said UC Davis professor Patricia Boeshaar. “The cost to go to the moon, build a station, harvest the Helium 3 and transport it back would be extremely expensive, not to mention the fact that most of the technology doesn’t exist.“
NICK MARKWITH can be reached at science@californiaaggie.com.