Posted on 05/20/2002 6:44:48 PM PDT by swarthyguy
BRITAIN’S first cowpat-fired power station will begin producing electricity before the end of the month, bringing a new meaning to the concept of wind power. The plant in Holsworthy, Devon, will use 146,000 tonnes of liquid slurry a year. As well as generating an estimated 1.4 megawatts for the National Grid, the plant will provide hot water to heat local public buildings.
Twenty-seven farmers have signed up to supply 450 tonnes of liquid slurry a day. It will be heated to encourage gas-producing bacteria and the residue returned to the farmers as concentrated organic fertiliser.
The Biogas plant took its first delivery last week and managers are awaiting a licence from the Environment Agency before they can begin production in earnest. The company hopes to establish 100 plants across England.
The Holsworthy Biogas project has been set up with a £3.5 million grant from the EU matched by a similar amount from the German company Farmatic, which already runs dung-fired power stations in Germany and Denmark. The scheme, known as a centralised anaerobic digestion plant, will run on a mixture of cattle, pig and poultry manure and food processing waste. The average dairy cow produces 56 litres of manure a day.
The mixture is pasteurised at 70C for an hour, then fed into a digester and held at 35C for 20 days. Anaerobic bacteria digest the mixture, producing methane which is used to drive the generators.
These are water-cooled and produce enough hot water to heat not only the plant but also to supply the heating to the town’s buildings. Managers plan eventually to offer the hot water to private residences as well as public buildings.
Graham Johnson, the plant manager, said: “We are using the town as a giant radiator. The water will be pumped down a pipeline in the town and come back as cold water. That will be the end of this year, early next. First, we will be producing electricity.”
Officials say that the de-gassed slurry removed after the process is an even better fertiliser for farmers than the orginal manure. Having been pasteurised, any pathogens, nematodes and weed seeds in the cow slurry have been destroyed. The liquid biofertiliser left from the process contains more plant nutrients and is 100 per cent organic.
As the methane has been driven off the smell is reduced by 90 per cent. Being liquid, the biofertiliser is readily absorbed, reducing the risk of pollution and run-off.
The average cow burps 280 litres of methane a day.
Why not here? More cowpatties and less oil from youknowwhere.
Yes. "Mad Max Beyond Thunderdome". From 1985, which may or may not be so old :-)
It is done. You just don't hear much about it, because the output is so little.
"As well as generating an estimated 1.4 megawatts for the National Grid, the plant will provide hot water to heat local public buildings."
A 1.4 Mw plant will provide the power for about 1,000 homes. Most of the new generating plants being built now are in the 300-600 Mw range.
I know of a dairy farmer in Oklahoma who built such a plant about fifteen years ago. It produced enough power to run his entire operation (a 1,000 head dairy farm) and sell a small quantity to the grid.
These so-called biomass plants are similar to windmills and solar power in that a.) they are environmentally friendly but b.) can't possibly supply more than a small fraction of our total energy needs.
Seems like a good idea!
Yes, it is. Considering what I've read about the pollution problems being caused by the mega-sized pig farms on the east coast, why are they not doing this? Too bad no mention of the cost per Kilowatt-hour for fuelling such a plant.
Your thought is correct, but you really ought to take another zero off your output. A home should be considered to take about 15Kw. OK, make that 14Kw for example. 1.4 megawatts is 1,400Kw which means it can supply 14 Kw to about 100 homes.
Just finished a project in the Portland area where a water treatment plant serves about 80,000 people. The solids are digested as in this article and the methane produced (about half as good a heating value as natural gas) runs a Cat generator which puts out about 0.3 megawatts. Not enough for 80,000 homes, but it backs out a significant amount of purchased power for the operations of the plant anyway.
Lagoons and sprayfields
Some people hear the word "lagoon" and picture blue water, surrounded by palm trees, perhaps, or with mountains in the background. A visit to a factory farm would quickly erase this beautiful image from their minds.
At factory farms, "lagoon" means an open-air pit filled with urine and manure. Lots of urine and manure -- some lagoons are larger than seven acres and contain as much as 20 to 45 million gallons of wastewater. The waste is collected with scrapers, flushing systems, or gravity flow gutters, and then stored in lagoons. Opportunities for disaster abound. The lagoons can leak or rupture, for instance, or they can be filled too high. But even if none of these problems occur, the lagoons still release gases. Their horrible stench and toxic chemicals harm workers and nearby residents.
Sprayfields are yet another threat. Manure is periodically pumped out of lagoons and sprayed on fields. Although manure can be an excellent fertilizer when it is applied at rates that crops can absorb, it must be safely -- and sensibly -- applied. But factory farms produce far more manure than their land requires, and they often overapply it to fields, causing it to run off the fields and into rivers and streams. Farmers may also spray when it is rainy or windy, or with little regard for adjacent property. In addition, the act of spraying wastes increases evaporation and vaporization of pollutants."
45 million gallons of pig sludge could probably generate a bit of methane-powered electricity. If cost-effective per KWH, better than leaving it in a lagoon, as anyone who has ever been downwind from a pig farm would know!
When it comes to biogas, that pigsty could outproduce any dairy farm in the state.
Meaning no disrespect to pigs, of course...
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.