Addressing green house gases in the atmosphere, which is the critical manmade components that contribute to climate change, is possible. Making that reduction in green house gasses in a socially and economically sound manner is the challenge. Projects that have produced alternate fuels, with the goal of energy independence, may have contributed to overall greenhouse emissions.
For example Brazil’s ethanol program: This program is a model for many nations’ seeking solutions to global warming and foreign oil dependence. How effective is Brazil’s ethanol program in reducing that nation’s carbon footprint?
Much of Brazil’s farmland was once rainforest. Deforestation is a major contributor to carbon dioxide levels in the atmosphere. Ethanol as a fuel, produces less atmospheric carbon dioxide than gasoline, but is not carbon neutral. Considering the production energy requirements from seedling to ethanol, there is less carbon dioxide released, but still considerable amounts are released. The net result of Brazil’s ethanol program may well be highly carbon positive.
I addition to carbon dioxide, decaying plant vegetation used as green manure (a fertilizer) releases methane which is also a greenhouse gas.
So Brazil’s ethanol program at best may have reduced the rate of carbon dioxide addition to the atmosphere. Most probably, Brazil’s program increases atmospheric carbon dioxide levels at a greater rate due to deforestation.
While bio-fuels appear to have a strong role in the transition for fossil fuels to renewable fuels, the choice of biomass is critical if atmospheric carbon dioxide levels are to be maintained or reduced.
Algae show much greater potential as a biomass that standard field crops. The advantages of algae are much higher energy production per pound of biomass, much less acreage required per pound of biomass and continuous harvesting of biomass. An additional advantage is that non-forested acreage unsuited to traditional farming can be used for algae production.
Common products from algae are bio-diesel, ethanol and high protein feed animal feeds. Using all of the algae for these purposes results in carbon neutrality of the crop. Other products can be made from algae that can make the crop carbon negative or sequester the carbon. Plastics, construction materials and soil enhancers (charcoals for nutrient retention) can be made from algae.
From a socially responsible position, algae farms are well suited for locations in the world where economic conditions cause great hardship. Algae farms can be located in areas of the world that experience frequent drought conditions. Saltwater which is plentiful in many of these areas can be used to grow algae and the bio-fuels from the algae can be used to power desalination plants. In politically stable, economically challenged nations, the value of the algae crop is sufficient to warrant outside investment.
The considerations that need to be made in finding real solutions to climate change and energy independence are enormous. The correct source of biomass is only one of those considerations.
(c)2007
Efficient alternate energy portable fuels are required to end our dependence on fossil fuels. Hydrogen holds the most promise in that reguard. Exploring the paths open for meeting the goal of energy independence is the object of this blog. Hopefully you will find it interesting and informative.
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