Solar Cell Advances

[RWebb]

"In the 1970s, manufacturing a solar cell required about as much energy as the cell could produce over its 20-year lifetime, so using solar power provided little if any energy gain. Also, as recently as 10 years ago, total emissions from solar cells were about twice what the new study shows."
-- Science News Online, Week of March 1, 2008; Vol. 173, No. 9 , p. 133
http://www.sciencenews.org/articles/20080301/fob5.asp

The pay back time now is only 1 to 3 years

[slodave]

Yup, good stuff. I installed 2 panels that drives an exhaust fan in my parents garage. With two modern cars that retain heat and a flat roof that bakes in summer, temps rise to about 115 degrees. With the fan, the temps are kept in th 90-100 range. Hot, but bearable for my mom. The fan has been running 24/7 for 3-4 years now. Nothing special, it starts when the panels get enough light and shuts off when the sun is gone. I have to adjust the panels about twice a year.

[island911]

These improvements in efficiency mean that today's solar panels can "pay back" in only 1 to 3 years the energy needed to make them, the study concludes.

... if you live on the Equator.


I'm just saying, payback time will really depend on location.

[dd74]

I live close(r) to the equator.

Randy - has market cost gone down for solar? It was pricey last I checked a couple years ago.

Maybe we can get a solar discount because Ed Begley Jr. lives in the neighborhood.

[MRM]

I live perfectly equidistant to the north pole and equater. The 45th paralel runs through a street one block over from my house. My old boss used to tease me about hating winter by pointing out I live only a couple hundred feet closer to the north pole than the equater. He lived on the south side of the block, so he could brag about it being warmer where he lived.

Wind is the best option up here. Flat land, lots of wind. Solar would make a nice supplement, though.

[ErVikingo]

I priced a system for my new house and after tax breaks it would still cost me approx $65K. The payback timing for this particular application is from 20-40 years (depending on the cost of electricity through time).

I'm still looking at installing some panels but it will not be to power part of my load (and sell on a net metering basis) but to power exhaust fans and the like. We are getting solar water and pool heaters.

Technology price point is still not where it would make perfect sense yet. Suggestions???

[Tobra]

If an air conditioner can get a 25 degree temp difference they would be happy with its efficiency.

Makes me like my wifes idea about making it mandatory on new construction.
Okay folks, how about this as part of our energy strategy


How many days a year is it sunny in San Diego or LA? I have already seen both fixed and mobile warning lights on the road in California with solar panels.

[charleskieffner]

anyone interested in doing solar here in the southwest , should contact tom bonner(neighbor/friend) of sun systems solar. the aps solar farm is just down the road from ASU in tempe and it cranks out quite abit of cheap power.

another month i will shut off my 30 amp breaker on my water heater and have FREE hot water until easily november.

has paid for itself in spades!


tom bonners partner is leslie neilsen(actor).

[vash]

the cost of admission is daunting. i want to do this badly.

[RWebb]

The 1-3 years includes the location effect.

There is quite a bit of solar power available at higher latitudes - including even areas like rainy and cloudy Oregon.

PV panels are cheaper now, but can still be pricey. A HUGE amount of VC money is going into solar companies right now, so I expect continued improvement.

One option is to install a hot water heating solar system, not a PV electricity generating system on the roof. I may do that this year. They can be as low as $6,000. YMMV

[charleskieffner]

rwebb where are you getting prices for a hot water system???????

jeezzzzzzzzzz louizzze

80 gallon water heater and plumbing w/collector was wayyyyyyyyyy cheaper than that! around $3300 complete and then i got my tax credits fed and state. my house is 2500sq ft 2 story 2 bathrooms. can take a hot shower til the cows come home !

another place you will notice solar is national forest campground lighting systems, and also flood control gauges/weather stations in remote areas. can be shot with a 30.06 repeatedly and will still produce power.

[einreb]

Originally Posted by charleskieffner

tom bonners partner is leslie neilsen(actor).

Shirley, you can't be serious.

[dd74]

Originally Posted by Tobra

How many days a year is it sunny in San Diego or LA? I have already seen both fixed and mobile warning lights on the road in California with solar panels.

It's sunny most days south of Santa Barbara, which is the beginning of SoCal proper (most northern point).

The fixed solar road signs/warning lights have been in operation for about ten years, IIRC.

[charleskieffner]

rodger rodger! neilsens home here is one of the "greenest of the greens". quite an advocate for solar here and abroad.

we iz da poster childs of solar!

pool solar(heat)

water heater solar

charge 12v vehicle batteries and trailer batteries via purple(new style)photovotaics.

many are unaware of the amounts of snowfall arizona receives during just an average year. entire salt/gila/verde drainages are monitored for storm inflows and snowpak runoff by remote(BFE) weather stations that monitor runoff thruout all major drainages. lesser drainages being added yearly to warn of flash floods. all powered by solar.

please note mars rovers powerpak part of which can be attributed to APS(az. public service solar farm) Univ.of AZ>(tucson) and ASU in tempe.

[silverc4s]

Here is a system that was patented by the late Jack Kilby, inventor of the integrated circuit, way back in 1977.
This never went anywhere, because at that time, the only working fuel cells were on the Space Shuttle & such and cost more than a house.
Check it out, it's a solar generating & energy storage system that could make each house stand alone on an energy basis, and is mass producible.
I have dreamed for many years about starting a company to make this type of system, once all the technology gets within reach..

United States Patent 4,021,323
Kilby , et al. May 3, 1977
Solar energy conversion


Abstract
Solar energy conversion is provided by a structure formed of a plurality of photovoltaic sources. An electrolyte wets the sources. Upon exposure to light the photovoltaic sources cause a current to flow in the electrolyte producing an electrochemical reaction. The products of this reaction may then be collected and stored. In a preferred embodiment the electrolyte is an aqueous solution of hydrogen iodide, and the hydrogen produced by the electrochemical reaction may be stored, burned as a fuel or used in a fuel cell to produce electrical energy.

[Rob Channell]

Here's a few facts followed by some opinion.

A quick analysis shows:
180 watt solar panel cost $567 from one website http://sunelec.com/
$567 here in Alabama buys 7560 kwh of electricity (0.075 per kwh)
180 watt solar panel produces 7560kwh in 42000 hours of good sunshine

Assuming 300 of 360 sunny days in a year and an average 10 hour day(probably a generous assumption here), payback point occurs after about 14 years. This does not take into account the time value of money or the opportunity cost of having this money tied up in solar cells instead of invested in a CD or stable bonds or something. I have seen incentives in other states to go this route, but Alabama doesn't seem to do that.

So for the solar cell idea......Wanna help the environment by using less grid electricity? great idea. Wanna save money? Not so great idea.

Of course if you pay 0.30 for a kwh of electricty the payback time drops down to 3.5-4 years and makes it a better deal.

I am about to replace a roof and would love the architectural shingles that have the solar cells built in but it just doesn't seem worth it in this part of the country.

There is at least one company using the DMD digital mirror devices to focus more of the light on the sensitive junctions of the solar cells. This should allow up to a 40% increase in efficiency, but the cost of manufacturing becomes more.


Just my 0.02....that's worth ~0.27 kwh around here.

[t951]

This thread lights me up.

Wife and I really want to do solar, but the cost isn't there yet. Neighbor did his water heater, and loves it.

[charleskieffner]

you would be amazed at how many solar collectors are in el dorado resort in san felipe baja norte. solar for power run to battery banks, solar for hot water heaters, solar on photovotaics for night illumination of property and very inexpensive rotary props picking up windpower and converting it to stored battery power for all electrical useage.

these are multi million dollar homes in mexican peso dollars so just vizualize how BIG they are to a compared million dollar home in the u.s!

[RWebb]

just saw in the paper today that Some ar talking about Oregon going to 20% solar in the near future (apparently 10-15 years)

I know the National Labs are messing with various solar schemes - a good friend of mine switched off of nuke-making several years ago to focus on melting sodium...

[red-beard]

I plan on solar heating my pool this year. It should extend the season into December. With just the cover on, the water was up to 71 last week. Until we had another cold spell. With a roof solar heating system, I should be able to keep it open nearly year round.