|
|
re: info on co-generators for home use
26 feb 1998
don kulha wrote:
>based on what i've seen and heard *in the long run* a gasoline generator
>will cost over 2x times the cost of solar photovoltaics (@ $0.16 kw) to
>source a 5kw/day load.
i guess you mean 5 kwh/day or 150 kwh/month, equivalent to about
200 continuous watts. very frugal, compared to typical household
electrical energy consumption.
>natural gas and cogen (heat recovery) would likely do as well or better.
suppose my $929 honda 1500 watt gasoline generator lasts 5,000 hours with
a 0.6 quart oil change every 100 hours, and makes 5,000x1.5 = 7500 kwh
which i illegally sell back to the grid (by making the meter run backwards
with a couple of variacs once in a while) at a retail price of 10 cents/kwh,
thereby saving $750 on my electric bill, while burning 5,000x0.23 = 1150
gallons of gas at $1/gallon and heating my house with 5000x9kw = 45,000 kwh
or 153,450k btu of heat, equivalent to burning about 1500 gallons of oil
at $1/gallon in a furnace with 80% efficiency. then the honda wears out,
and i throw it away and buy another.
were my house oil-heated, i would save $1500 in heating and $750 in
electricity, while spending $929 + $1150 + $50 (oil changes), thus
saving $2250 while spending $2129, which seems like a net cost of
-$121/7500 or roughly minus 2 cents per kwh, in this situation :-)
>generators are complex mechanical things...a good thing to have but not a
>good thing to depend on long term imho.
so you'd rather depend on a solar panel made in some multimillion dollar
factory in singapore owned by an oil company and staffed by guys in lab
coats murmuring mumbo-jumbo into their mysterious machines than an engine
that can be repaired by a mechanic around the block? where can we buy those
little italian air-cooled diesels they hook up to auto alternators to run
the large incandescent bulb arrow signs used during highway construction?
nick
|
|
