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: http://zebu.uoregon.edu/1999/ph162/l17.html
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The McNeil Generating Station in Burlington, Vermont, generates 50 MW of electric power for the city's residents using wood from nearby forestry operations-forest thinnings and discarded wood pallets. The gasifier is capable of converting 200 tons of wood chips per day into a gaseous fuel that is currently fed directly into the McNeil Station boiler, enough to generate 8 MW.
Biomass
In general, biomass burning is perceived as being a sensible form
of energy generation.
Biomass power (biomass-to-electricity power generation) is a proven electricity generating option in the
United States.
converting organic matter into energy. The energy source
is stored solar energy. Heating via woodburning is an example of
using biomass as an energy source.
All of today's biomass power capacity is based on mature, direct combustion boiler/steam turbine technology. The average size of existing biomass power plants is 20 MW (the largest approaches 75 MW), and the industry average biomass-to-electricity efficiency is 20 percent.
Advanced technologies:
Gasification technology can convert biomass into a liquid or gas that can be burned in a combustion turbine. Gasification technology has not been fully developed and has not yet been demonstrated in commercial power plants. However, it has some great potential advantages including a low capital cost, high efficiency even in small plant sizes, and low pollution emissions.
A Case Study in BioMass Cogeneartion
Okay, let's look at this with a critical eye:
Some common forms of biomass from which energy can be extracted:
Most biomass is made of Carbon and Hydrogen (e.g. Methane = CH4)
Half of the World cooks with wood. In developing countries, biomass accounts for about 70% of the energy generated
In the US, there are now wood waste power plants that have a capacity of 80--100 Megawatts; approximately 10% of the capacity of a coal fired steam plant.
Production Line Strategies for increasing the power yield:
Example Calculation:
15 tons/acre yr * 350 x 106 acres * 7500 BTU/lb * 2000 lb/ton
=79 x1015 BTU
In 1990, the total energy used in the US was 81 x1015 BTU
So the potential is there for a substantial fraction of our energy
budget to come from biomass burning.
Only 5% of a plant's total biomass is suitable for food. There are two
alternatives for the remaining 95%:
Conversion of biomass into fuel is somewhat inefficient and costly.
At present, its best to just burn the biomass in electrical power
plants.
Conversion of corn into fuel:
At the moment the production of ethanol and methanol is subsidized
7500 BTUs
lots of fossil fuels are used in
agriculture to grow the corn in the first place
In other countries, the econmics of biomass conversion are more viable:
Converting biomass to Methane:
But, BE WARNED, current agriculturual processes have a heavy reliance on fossil fuels and this reliance is often hidden
Current Air Pollution from BioMass Burning:
Read More about it:
Other Problems:
need to burn on site