PGAQ #13 (Cit) by Vic Steblin, Feb 17, 2008

2570 Laurier Crescent, Prince George, BC, 250-564-1123

I have read accounts of the proposed Community Energy System (CES) for downtown Prince George which is supposed to burn about 10 tonnes of wood waste per day while producing only about 2.5 kg of fine particulate per day. How am I to understand these numbers and ratio? Who has determined this ratio and what is the background science? Do I just believe what I am told without question? I am further told that 2.5 kg of fine particulate can be produced by one older wood stove in three or four days. A single city bus can produce 2.5 kg of fine particulate in one week. These comparisons seem very supportive for the CES. But how do we really compare the quantity and quality of emissions? Are diesel emissions equal to wood particulate by weight?

In my opinion a fair estimate of quantity produced by burning also comes from considering the total mass of the fuel involved. The total resultant air bound waste has to go somewhere, and it includes all sizes of particles plus gases, all of which has some chance of getting into our lungs. Starting material that is ultimately burned allows us to roughly compare the total impact of industrial stacks, residential wood stoves, all vehicles, all natural gas users, all smokers, all lawnmowers, etc.

Interesting questions follow. How many residential wood stoves does it take to burn 10 tonnes of wood waste per day? How many city buses can be run on 10 tonnes of fuel per day? How many cigarettes would be in 10 tonnes? How many lawns can be cut with 10 tonnes of fuel? It seems just as fair to consider total emissions this way! And now the CES does not seem so attractive!