[Vwdiesel] Payback on Solar and Other Alternate Energy Projects

[Roger Brown]

Sandy Cameron wrote:
> I have 30 watts worth of Solar (+charge controler) up at our camp, (30 ft
> trailer) which has charged the same 90AH battery for more than 5 years,
> pumps water for the kichen, bath, shower, etc, CFs via small inverter, 13'
> tv, radio, etc.

I too have a small 30 watt panel charging some old 12V batteries.  That runs a thermostat 
controlled 12V fan that pulls sun-heated air out of the covered porch behind my house and 
blows it inside for heating.  Almost an ideal photovoltaic setup as the air is only heated 
when the sun is shining.  But that pretty much heats my house (SF Bay Area in CA), have 
not had the furnace pilot light on for years.  Wood stove provides any supplemental heat 
needed, used maybe 10 days/year.  Cost $200 for the system and I'm guessing it has paid 
for itself in just the year I have had it installed.

Also put in some solar powered floodlights behind and beside my house.  I think those paid 
for themselves instantly just in savings for running wiring out to them.  Figuring the 
cost of running outside, weather tight conduit, junction boxes, etc. to install a 120V 
light, that would exceed the $40-50/unit cost of the solar lights, not to mention the time 
savings on the install, 2 screws and stick the panel on the roof and they are ready to go. 
  And the 1watt Luxeon LED in the spotlights puts out a very nice light, enough to read by 
but not enough to blind you if you look at it.  Has enough battery capacity for ~3 hours 
of light, motion sensor to turn the light on and off automatically.

Looked into doing solar for the house, local utility offers a $4500/KW rebate for 
installs, a 4KW system would be around $18-20K net cost and would have ~8-10 year payback 
with supplying approx. 50% of my electricity needs over a year.    Looking at the panels, 
I'm thinking once they can get panels into the 400watt range, you could do that same 
system in about 10 panels.  Then you could consider adding sun-trackers on each panel and 
that would nearly double the daily power output.  If they can get those panels down to the 
same cost as the ~200 watt panels are now, that sort of system would be very attractive. 
Would supply nearly 100% of my electricity and with similar utility rebates, could be a 
lot lower net cost.

-- 

   Roger