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Re: 'Zoo eyes dung deal to generate power,' News, Oct. 31

Before we spend $13 million on an anaerobic composting plant to generate electricity we should do more thinking and stop making unfounded claims. (Electricity for 10,000 to 15,000 houses; you must be kidding, maybe 100.)

In Toronto, we already have one plant for processing organic waste (from the green box collection) using anaerobic composters. (By the way, how many megawatts are generated at that plant?) There is a simple way to establish the potential of the zoo dung. Organize a dung shuttle from the zoo to the existing plant and run full-size tests with the dung for one week. The tests will provide data on the quantity and quality of the methane available from the dung. The data will also serve to determine the real capacity of the zoo dung processing plant.

In the article, the claim that the waste would be transferred 'into up to 2.8 megawatts of power a year' cannot be accurate. That comes to 7.76 kilowatts per day - hardly enough for one house.

The second statement is even more bizarre: 'The technology collects methane gas from composting biowaste, and pushes it through turbines under pressure. There's no combustion, and zoo staff said the only by-product is highly concentrated fertilizer,' The undisputed law of thermodynamics is that the energy of methane can only be released by methane combustion, resulting in emission of carbon dioxide and water vapor.

Mario Gasparovic