Portable Solar Power - Page 3

 



Let's do some math.  A good generator might last you 5,000 hours at best.
That's about 7 months.  If the generator cost $2000, that translates to
$3428/yr. Fuel consumption is about one liter per kilowatt hour.  Gasoline
is currently approaching $0.90/L.

The average home uses about 600 kWh per month, or 7200 kWh per year.  The
fuel alone would cost over $5000 a year, plus the generator replacement cost
of $3400 = $8400 per year.  This equates to $1.16 per kWh, which is well
over 10X the average rate for grid power in most areas of the country.

My figures are very ballpark, but no amount of figuring could make a
generator economical enough to use on a constant basis.

 



About 12K hours, for a $900 1800 W Honda.


The average is closer to 10K kWh/year.


Try including the useful heat output, about 4X the electrical output.

Nick

 



So how do you manage that? Duct the heat from the engine into the house?
Only on cold days?  Like the smell of exhaust?

The numbers can vary a lot, but never enough to disprove my point that a
generator is far too uneconomical to run on a continuous basis in most
cases.  Nice try. If you live in Antarctica, I may retract my argument.

 



Well? You wanted to "do some math" :-)


Put it in a poly film room in the basement, depressurized by its exhaust.


Yes. No. Intelligen's Lister-Petter 11 HP cogen system lived in US basements
and started up with a room temp thermostat and ran till the house was warm,
meanwhile pushing the meter backwards at 5 kW, with a 93% CHP efficiency.


I disagree. Cogen was widespread in the 1930s. Try the numbers, if you like.

Nick

 



Yeah, before there was a grid.  That was also a time when you had maybe 2 or
3 appliances that you used infrequently.  When the grid became available, it
was almost a total conversion, practically overnight because of cost
advantages.

By the way, it wasn't co-gen. In those days, there was no way to synchronize
different generators, so every little town and farm had their own generator.