andreask@watson.bcm.tmc.edu (Andreas Kasenides) (01/10/90)
I am very much interested in solar energy as a means of powering up
household devices ( lamps, heaters, AC's etc ) and not just as a means
to recharge my rechargable batteries ( which I do not use very often
anyway ).
I would like to know and get the opinion of those on the net that have
experience on this subject. Specifically
1) Is it feasible ?
2) What are the requirements ?
3) Is conversion of solar energy, say, to heat rather than electricity
more desirable.
4) Will the cost of the system make it economically unsound ?
I can summarize if enough interest is shown. Please ask me to summarize !
Thank You.
----------------------------------------------------------------------------
Andreas Kasenides
andreask@bcm.tmc.edu
-----------------------------------------------------------------------------josef@peun11.uucp (Moellers) (01/11/90)
andreask@watson.bcm.tmc.edu (Andreas Kasenides) writes: >I am very much interested in solar energy as a means of powering up >household devices ( lamps, heaters, AC's etc ) and not just as a means >to recharge my rechargable batteries ( which I do not use very often >anyway ). Me too! >I can summarize if enough interest is shown. Please ask me to summarize ! Yes please! Josef Moellers | c/o Nixdorf Computer AG USA: uunet!philabs!linus!nixbur!mollers.pad | Abt. DX-PC !USA: mcvax!unido!nixpbe!mollers.pad | Pontanusstr Phone: (+49) 5251 146245 | D-4790 Paderborn
davidc@vlsisj.VLSI.COM (David Chapman) (01/12/90)
In article <122@gazette.bcm.tmc.edu> andreask@watson.bcm.tmc.edu (Andreas Kasenides) writes: >I am very much interested in solar energy as a means of powering up >household devices ( lamps, heaters, AC's etc ) and not just as a means >to recharge my rechargable batteries ( which I do not use very often >anyway ). > >I would like to know and get the opinion of those on the net that have >experience on this subject. Specifically > > 1) Is it feasible ? > 2) What are the requirements ? > 3) Is conversion of solar energy, say, to heat rather than electricity > more desirable. > 4) Will the cost of the system make it economically unsound ? Solar heating is extremely effective in middle latitude climates if it is designed into the building. The payoff can be much longer if you have to retrofit but is almost always worth investigating if only from an environmental perspective. In any energy supply conversion, you have to determine the amount of money that your current energy source costs per hour (since its capital expense is likely paid off). Then compute the capital cost of the conversion and divide this by your current energy cost. This tells you how many years it will take to pay off the conversion. If you're very interested in saving the environment by using renewable energy sources, this period can be a long time. If you're a business owner with angry stockholders, this will be a shorter time (but do it if you can). I think 7 years or so is reasonable for homeowner projects. As for specific conversions: if you're interested in powering appliances etc. you almost have to use the solar system or backup utility power to charge a bank of batteries, then run the appliances off of the batteries. This by the way is how the best UPS systems run. Quite naturally this can get expensive. If you're willing to have separate circuits and switch to another light, heater, or AC system when the sun goes down or behind a cloud, then it can be a lot cheaper. Oh, by the way, don't use solar cells for heating. Direct solar heating will be much more efficient because the conversion factor for solar cells into electricity is 10% or less. You're much better off using the heat directly. You can get an idea of how expensive solar cells are by visiting your local marine or RV supply house. Boats in particular often don't have extension cords long enough to power their refrigerators :-). One of these days I'm going to look into solar panels to power the refrigerator in my VW camper. The 50 AH deep-cycle marine battery (size of a regular car battery) only runs the fridge 10 hours, and if I don't drive for a day or so everything spoils. Interesting story: last summer, while riding down the Pacific Coast on a bicycle, I met someone who was walking from San Francisco to San Diego. He had a 16-watt solar panel attached to the top of his backpack, almost as a parasol. This in turn powered a Zenith laptop. He was writing a book as he walked! These solar panels, by the way, were amorphous: lower efficiency, but (I think) cheaper than the silicon-wafer ones and *much* less fragile. You could bend them. >I can summarize if enough interest is shown. Please ask me to summarize ! Yeah, yeah, you wanted E-mail rather than posting, but I decided that my response was of general interest. :-) Net mail tends to bounce anyway. And finally, with a message this long I can waste much more net.bandwidth by posting than by mailing. :-) :-) :-) -- David Chapman {known world}!decwrl!vlsisj!fndry!davidc vlsisj!fndry!davidc@decwrl.dec.com
wordy@cup.portal.com (Steven K Roberts) (01/14/90)
An excellent resource for anyone interested in home solar power is
Home Power Magazine
P.O. Box 130
Hornbrook, CA 96044
it's currently free, but will become $1/issue soon. Still a spectacular
deal -- these people are creative and very much in touch with the
real needs and real technology.
Personal note -- it works great. I've been powering all the systems
on my bicycle for years with Solarex panels, and that includes in the
new system 8 computers (including a Mac portable and a 286), satcom,
celphone, active cooling, and a lot more. Very practical stuff, solar,
at least outside the Pacific Northwest!
-Steve Roberts, Nomadic Research Labsroy@phri.nyu.edu (Roy Smith) (01/14/90)
In <15437@vlsisj.VLSI.COM> davidc@vlsisj.UUCP (David Chapman) writes: > You can get an idea of how expensive solar cells are by visiting your local > marine or RV supply house. Indeed. E & B Discount Marine (one of the big catalogs) lists a "high output" solar panel which develops 5 W (presumably this means in bright sunlight) for $98.95. Not very cost effective. -- Roy Smith, Public Health Research Institute 455 First Avenue, New York, NY 10016 roy@alanine.phri.nyu.edu -OR- {att,philabs,cmcl2,rutgers,hombre}!phri!roy "My karma ran over my dogma"
sorka@ucscb.UCSC.EDU (Alan Waterman) (01/14/90)
If you are talking about the Japanese developed, fold up flexible solar cells(about 1.5 x 1.5 feet), then you are wrong about them being less efficient. In fact they are much more efficient than traditional photoelectric cells.
george@wombat.UUCP (George Scolaro) (01/15/90)
In article <1990Jan14.021014.26614@phri.nyu.edu> roy@phri.nyu.edu (Roy Smith) writes: >In <15437@vlsisj.VLSI.COM> davidc@vlsisj.UUCP (David Chapman) writes: >> You can get an idea of how expensive solar cells are by visiting your local >> marine or RV supply house. > > Indeed. E & B Discount Marine (one of the big catalogs) lists a >"high output" solar panel which develops 5 W (presumably this means in bright >sunlight) for $98.95. Not very cost effective. Checking out marine and RV places is not the best way to find out about solar panel prices. These places are very expensive (they cater for people with more money than they need, ie recreational activities). If you want to get realistic prices, call Solarex. They manufacture and distribute solar panels world wide. The panels are made from marine grade materials and are designed for real world use, i.e. unattended outdoor use. I use one of their 40 watt panels in australia for charging a 12 v gell cell that runs a small Engel fridge (to keep essentials cool) while out bush. Telecom Australia uses lots of their panels for powering remote repeaters and telephones (yes I have called home from a solar powered telephone!). The panel cost around AUS$400 a couple of years ago, and on last checking the price over here (in the USA) they was cheaper, exchange rate etc. They also have more efficient panels now. The 40 watt panel is approx. 1 metre x 1/2 metre x 3 cm. best regards, -- George Scolaro george@wombat (try {pyramid|sun|vsi1|killer} !daver!wombat!george) [37 20 51 N / 122 03 07 W]