USING BIOMASS AS A RENEWABLE ENERGY SOURCE
The term biomass
casually refers to biological material that can be used as fuel. It can be something as simple as a wooden log or more complex like alcohol. Biomass for millennia has been the primary energy source on the planet.
Although it is considered that all fossil fuels such as coal and oil are originated from buried ancient organisms, they
are usually excluded from the definition of biomass.
Plants are a common source of biomaterials. Corn, for instance, can be processed to make liquid automotive fuel, and wood can be burned for heat energy. Other sources include residue from forests, such as grass clippings and fallen leaves. Many plants can be turned into industrial fuel, including willow, corn, and hemp. Structures like these can be harnessed and used for energy. Since they can be grown again, this energy source is fully renewable. Another important source of biomass in the home is garbage, which is approximately 60% biomass.
HOW CAN BIOMASS BE USED TO GENERATE ENERGY?
The easiest and most efficient way to use biomass as energy is to burn it. When it is burned, a part of the internal chemical energy convers to heat. For some homeowners, certain types of garbage can be burned to heat their homes, although this is not always a practical in a modern home.
Biomass can also be burned in special plants called waste-to-energy plants
. These plants use the heat energy to create steam, which is then used to either heat buildings or create electricity. In the about one hundred waste-to-energy plants currently operating in the United States, garbage is burned to create enough electricity to power about 3 million homes.
Not only do waste-to-energy plants create electricity using a renewable resource, but they also allow us to cut down on the amount of trash placed in the landfills each year. Since the average American creates over 1,600 pounds of waste each year, this is an even more important benefit of waste-to-energy plants than the electricity they produce. In addition to creating electricity and heat, biomass can also be used to create methane gas, ethanol, and biodiesel. Methane gas, the primary component of natural gas, comes from rotting waste, and this gas can be harvested.
Sugar cane and corn are converted into ethanol, a fuel used to power vehicles. Leftover oils and fats are used to make biodiesel, another fuel used to power vehicles.
PROS AND CONS
The main benefit of biomass is it's a renewable fuel. Not only does this give us a renewable source of energy to heat our homes, power our vehicles, and produce electricity, but it also helps us eliminate some of the waste we are throwing out there for the next generation to deal with. However, if not managed carefully, biomass can be harvested at unsustainable rates, damage ecosystems, and consume large amounts of water. Technically, biomass is the only renewable source that theoretically can be depleted. Another drawback of using biomass as a fuel is this process produces air pollution such as of carbon monoxide, nitrogen oxides, and volatile organic compounds.
While it is not unusual for homes to be heated with firewood, other types of bio-materials are not as common, and their commercial-scale use is currently very limited. In 2010 only about 0.5% of total US energy consumption came from biomass waste and 1.6% from biofuels. Aside from high utility-scale cost, our energy demand is outpacing biomass production even with the fastest-growing known energy crops. Meeting a significant portion of the growing primary energy demand with the use of existing types of plants would require unreasonably large land areas. It is therefore important to explore the ways of designing bio-organisms that could be transformed into usable energy in a more effective way while keeping the pollution levels low.