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Like it or not there are millions of acres of landfills
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in the US and elsewhere, these represent vast sources of greenhouse gasses and
pollution.
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When capped these landfills can be utilized as sources of energy. Anaerobic bacteria decompose organic
waste over time and can yield about a cubic foot of methane per pound of trash. It doesn't sound like
much, but it is.
In an article in Industrial WaterWorld Nov/Dec 2006, mention is given to a 260 acre landfill in Salem
Township, Washtenaw County, MI which has has 3 30MW gas turbines. So that's 90MW/260 acre or about
346kW/acre.
We'd install combined solar/thermal systems rated at approximately 845kW/acre (445 solar + 400
thermal). Even more important, unlike each of the 30 MW turbine plants, the STS could be installed
gradually, an acre or two at a time. This allows each incremental addition to pay for itself, and that the
landfill need not be one of monster proportions, to start producing energy.
The energy extracted from the CH4 from each acre represents about 8.3 MWh/acre/day. The
waste heat from the gas turbines, could be easily amount to another 10MWh/acre/day.
Every one of those acres also absorbs about 12.5 MWh/acre/day of raw sunlight.
Addition of the STS in this typical example can increase the energy production of the landfill, from double
during the overnight, to triple during the day.
An STS system placed on that land could provide additional output without disrupting the landfill.
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They made this article
really difficult to link to, if you cant access this try www.industrialww.com the article is by Jim Jackson
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