Diamond, Craig (DiamondC@mail.ci.tlh.fl.us)
Tue, 9 Feb 1999 17:04:10 -0500

My point is that unless the energy costs of converting, say coal, to
electricity are included in those numbers it is _possible_ that the real
savings are closer to 900 kwh/ton (as coal).

When folk compare energy requirements that involve _different_ fuels (like
electricity for cooking glass) versus diesel for collecting and hauling
recycled goods you need to make sure that the conversion efficiencies are
accounted for. A kwh of electricity is worth 3-4 kwh of heat in the form of
fossil fuel, that is you've got to burn 3-4 units of fossil fuel to get 1
unit of electricity.

I don't know how the calculations were done - maybe it was in an earlier
discussion and I jumped over it. If it is already accounted for then yes,
you shouldn't haul more than 240 miles; if it isnt you've got much more
flexibility in hauling, pre-processing and other programmatic aspects.

This was just a caution about how things are reported. Clearly the optimal
strategy depends heavily on how you conduct your analysis.

Craig Diamond, Chief - Environmental Planning
Tallahassee - Leon County Planning Department
300 South Adams
Tallahassee, FL 32301
Phone: 850/891-8621; FAX: 850/891-8734