n and
but that doesn't change that the first 2kW you use while the sun is up will be free, you don't have to run exclusively on solar
ear
ing
you
ear,
unless you intend to supply electric to the grid why would you have to sign up for anything?
what if you had a generator or just decide to save electricity, that would be the same thing
-Lasse
Yes, the general opinion is solar hot water has the fastest pay back. But with a drawback that the systems are more complex and most likey to be neglected.
There is also geo-thermal heating and cooling, lots here on LI. The pumps use electricity, but the savings on fuel out weigh that.
Cheers
No. Everyone lies, but that's ok because nobody listens.
As one of those writers (content providers), I'm quite impartial and will weigh the bribes and incentives provided by all sides of an issue with impartiality. What do you offer for me to support your position?
Well, if you're confused by factoids and figurines, I suggest you look at just the big numbers. The little ones will of course have an effect, but it's the numbers with lots of digits after the dollar sign that have the biggest impact on financial viability. To favor your speculation, I'll make some simplifying assumptions.
Ok, now for the guesswork. A fair size system should be about 10Kw maximum output. Solarworld 270 watt panels are selling for about $300/ea. Matching Enphase micro-inverters cost about $130/ea. The central controller is about $1,800. Therefore, the up front costs would be: 40 panels at $300/ea $12,000 Install $8,000 40 microinverters $5,200 Frames and mounts $4,000 Drivel and Trivia $3,000 ========================================= Total $32,200
Assuming a conversion efficiency of about 80% (including all losses),
40 panels will produce: kw-hr/year = 40 * 0.270 kw * 5 hrs/day * 365 day/year * 0.80 = 15,800 kw-hr/yearThat will reduce the consumption part of the electric bill by: 10,800 kw-hr/year * $0.15/kw-hr = $1,600/year The $0.03 credit from the electric utility for selling them surplus power will be at: Power produced - Power consumed = Power sold 15,800 kw-hr/year - 10,800 kw-hr/year = 5,000 kw-hr which is worth: 5,000 kw-hr * $0.03 = $150 Therefore, the value of the electricity produced is: $1,600 + $150 = $1,750/year
Break even is: $32,200 / $1,750/year = 18.4 years.
Not great, but still better than the 25-30 year life of the array. The incentives, credits, and deductions that you insist on ignoring will reduce the break even point a few years.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Most installation are grid tied systems, which don't use batteries. For battery type systems, the lifetime varies but seems to settle at about 5-10 years for "typical" installations. Much depends on maintenance (equalization, terminal cleaning, adding DI water, etc) and the local environment (sand storms, falling branches, vibration, etc).
Most current panels will last 40 years, with a guarantee that they'll put out 80% of rated power at 20 years.
Finding repair and replacement parts after 20 years may be a serious problem.
There are non-penetrating roof mount systems that reduce the problem. They're more appropriate for the flat roofs found on industrial buildings, but can be used on some shed roofs. Maintenance of anything that's expected to last nearly forever is going to be a problem. With the dramatic rise in solar power installations, long term issues are probably not an immediate concern, but will need to be addressed eventually.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Sure -- except, below.
ISTR the "incentives"/subsidies are tied to your doing exactly this!
E.g., you can (have been able to for a long time) sign up for Time-of-Use tariff. You are encouraged to shift your load to "off peak" hours. But, the usage that you *don't* shift is charged a much higher rate.
Bottom line, it's virtually impossible to save money on this plan -- even though your total energy consumption decreases! E.g., I do most of my "living" in those off-peak hours. But, the house still needs to be cooled during those hours, the refrigerator/freezer still need to run, etc.
[Businesses, charged on *peak* usage, often invest insane amounts of money to LEVEL their loads -- including "making ice" at night to lessen the effort required to cool the building during the day, when it is occupied]No one incentivizes me to have a genset.
Actually, solar *pool* heating is a sure-fire choice. But, that assumes you *want* to heat the pool that much (I've been in passively heated pools where it felt like BATH water!)
The cleverest scheme I've seen uses the thermal mass of the pool water to cool the "exhaust gas" from a whole house air conditioner (and, in the process, heat the pool water). Aside from a bit of pipe (which can be PVC) and the actual heat exchanger, no real moving parts (a valve), maintenance, etc.
Of course, assumes your keen on taking on the cost/maintenance of a *pool*...
[We've thought of going this route with an "infinite pool"... though not sure we even want *that* much maintenance!]
Of course you have to figure in government subsidies for fossil carbon - li ke depletion allowances, and the military defending remote fossil carbon fi elds, pile-lines and shipping lanes - when you are doing the sums.
Serious analysis throws in the cost of dumping CO2 in the atmosphere and ma kes estimates of the long term costs of anthropogenic global warming.
One of them is sea level rise - about 10 metres worth, when the Greenland (
6 metres) and West Antarctic (4 metres) ice sheets slide off into the ocean .Every port city on the planet - very expensive real estate - is going to ge t trashed when that happens.
You've been brainwashed by the denialist propaganda machine.
Whereas the fossil-carbon subsidies are as secure as death and taxes.
Probably not. And it's a lot easier to hose off your roof than it is get at a marine installation.
Electronics mostly doesn't have wear-out mechanisms. Badly designed electro lytics may be an exception.
Wind-power has apparently hit break-even. Solar has a way to go - until we start charging the fossil-carbon-burning brigade a reasonable fee for using the atmosphere as CO2 dump.
The only stuff I've read claimed that solar came out generating about seven times as much energy as it cost to build the generating gear. Concentrated thermal solar power came out at about nineteen times the cost of construct ion.
The Wikipedia entry says much the same - but it does point out that the fig ure is heavily technology dependent.
Because the article I was reading was clearly denialist rubbish, the autho r went on to argue that seven times the cost of production wasn't enough of margin to sustain a modern industrial society (which is hard to take serio usly, since he didn't adduce any evidence at all to support the proposition ).
Why "mostly recycled"? That doesn't save all that much energy. There's at l east as much energy in cutting and shaping as there was in the original ext raction.
The Wikipedia article puts wind turbines as yielding some eighteen times as much energy as it cost to build the wind-turbine, generator and so forth.
-- Bill Sloman, Sydney
Copyright 2008 and earlier. Since then, China has halved the cost of solar panels, by upping the production volume by a factor of ten, putting the Ger man's noses severely out of joint, because they'd got a large slice of the market a few years earlier by doing exactly the same thing. Don Lancaster p robably didn't notice when that happened either.
-- Bill Sloman, Sydney
This crops up every so often on news:uk.d-i-y. Short version is that if everyone installed PV the planet's energy consumption would increase, and power bills would go up massively. PV only makes sense when connecting to the grid would cost arms & legs.
Solar hot water can make sense, but only with a good design and diy install. Professional systems are pretty much nonstarters for ROI.
NT
veryone installed PV the planet's energy consumption would increase,
Wrong.
They'd roughly double.
Not exactly true. Buying power from the grid is expensive - you pay as much for the cost of distributing the power as you do for the cost of generatin g it.
Today's solar panels are cheap enough that you can make a profit on the bas is that what you generate locally save you from having to buy that power fr om the grid.
Carried to it's logical conclusion, this would bankrupt the grid and the bi g generating stations whose power the grid was designed to distribute - the grid isn't going to get any cheaper just because it isn't carrying as much power, and the big generating plants are only going to be selling power at night and when the sun is behind a cloud. In reality, domestic PV is never going to be popular enough to make much difference - it's a big capital in vestment with a fairly long pay-off time.
ll. Professional systems are pretty much nonstarters for ROI.
DIY install is only cheap because you don't charge for your own labour - ty pically it's going to take you twice as long to instal your stuff as it wou ld a professional, and there's much less chance that the professional will screw up the installation.
-- Bill Sloman, Sydney
Compared to what? You need to amortize the cost of all the wars we fight in the Middle East. You need to include the cost of cleaning up coal mines, disposal of nuclear waste, lives cut short due to pollution, etc. Nuclear power is heavily subsidized.
We need to make the Middle East irrelevant. More solar, wind, and hydro. Make a better car battery. Then the Middle East can fight their holy wars to their hearts content because we won't give a shit.
I tend to agree with your analysis. The thing with solar is you should have an all electric house, which isn't all that common out here on the left coast. If you ran a heat pump and electric stove of some flavor (resistance or induction), you could justify the cost of solar. You see this in late model custom homes.
The deal in California is all you get are credits for power generated, It isn't like the utility company will pay you. It is very regressive thinking. Quite illogical, but paying off politicians made it happen.
There are even more f***ed up states such as Arizona, where they charge you to have solar power. Same with Florida. I don't know which party to blame (cough cough GOP GOP).
Bill Sloman wrote in news: snipped-for-privacy@googlegroups.com:
Most leisure marine installations get hosed off whenever the vessel returns to the marina. Most navigation buoy installations get inspected annually and preventative maintenance including cleaning is done. Domestic installations on pitched roofs are usually not easy to access for cleaning and special equipment and training may be required if it is to be done safely.
Windpower only beats break-even if it reaches or at least comes close to its design lifespan. In the Thames Estuary, some wind turbines in an approximately ten year old windfarm are already on their second replacement gearbox. The design life was supposed to be 20 years but large numbers of failures are occuring in half that period. Elsewhere up the East Coast, foundation failures are occuring at half the design life or less.
Small scale generators using repurposed automotive alternators etc. avoid a lot of the initial energy cost as it is already amortised over the life of the donor vehicle. However the energy costs of producing electrical grade copper, steel and especially aluminium from raw ore are high if you honestly cost in extraction and transport and any saving that does not impact design lifespan is worth having.
-- Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED) ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk [at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL
I'm not surprised to hear that English engineering has the same proportion of useless twits that it did when I was working there. It is possible to de sign wind-turbines so that they last as long as they are supposed to - the German and Dutch designs don't seem to be breaking down unusually frequentl y - but in England there's a tendency to confuse an upper-class accent with leadership skills.
Repurposed automotive alternators may look like serious wind generators to you, and to the people who put up short-lived off-shore may be equally sill y, but this isn't a claim that does anything for your credibility.
I cite Wikipedia when what it says fits what I know from other sources, as that article does. It cites 23 references, which is 23 more than you could find.
-- Bill Sloman, Sydney
Looks like all the usual suspects...
-- Rick
I seldom use Wikipedia as a reference unless it is a topic I know enough about that I can tell if they are hosed... which I *have* found more than once. Even then for any fact I am citing I look for the original reference and if important actually verify the info in that reference. Once I found that the wiki article completely reversed the point in the reference and gave completely wrong info in spite of having the reference.
-- Rick
It looks this this thread has degenerated into the usual line of crap this newsgroup is so good at producing.
I was going to suggest that a relatively easy way to tell is to get a quote on a specific system, estimate how much power you would get from it in your area and factor in the *real* cost of electricity, reduction in what you buy, vs what the power company will pay you for your excess (if they do).
In Maryland the utility is required to pay you "full price" for your electricity. But now that they deregulated the price only includes generation and not distribution or transmission. I think they are getting some "free" money since that is electricity they don't have to pay transmission costs to get and I expect that is not factored into how they bill transmission costs. However, that is likely not much of a factor to the general public as yet, but it is to the few who sell power back to the utility company.
So is this something you are thinking about doing or just looking for a topic for getting the group wound up about?
-- Rick
Ian Malcolm
Bill Sloman
Bill, why do you go out of your way to reduce any discussion to hurling silly insults ?
from
" The Danish firm Vestas, which makes the turbines, said the new gearboxes were an improved design. "
AFIK most of the wind turbines in use in the UK are manufactured elsewhere in Europe - not necessarily a good thing but relevant in this context.
Ian makes a perfectly reasonable point - before you slag it off with your usual anti English bile you could at least do a little basic research.
Michael Kellett
Two cases are an easy win:
- You're using a lot of power during peak day hours and the power company has put you on a variable rate.
- You're facing a choice between adding solar panels or adding power lines.
These are why you'll see data centers and remote hotels with solar panels and other "green" tech. They're running air conditioning and they're near the limit of how much cheap power they can buy. They're becoming popular with highways too - illuminated signs, emergency call boxes, traffic control, low power comms, etc. The cost of stringing wires out to a few remote boxes makes solar panels and batteries seem cheap.
I checked out solar for where I am and it would likely come to a loss. Maybe that will change if a few more neighbors with gas guzzlers buy tiny electric cars for commuting to work.
-- I will not see posts from astraweb, theremailer, dizum, or google because they host Usenet flooders.
to
re
nion of useless twits that it did when I was working there. It is possible t o design wind-turbines so that they last as long as they are supposed to - the German and Dutch designs don't seem to be breaking down unusually frequ ently - but in England there's a tendency to confuse an upper-class accent with leadership skills.
Lots of engineering is selecting the right component - picking the wrong su b-contractor isn't exactly evidence of competence.
h.
That wasn't anti-English bile - it was the result of 20 years working in th e UK in engineering - from 1973 to 1993. Lots of the engineering done in th e UK is first class, but there were some salient exceptions, reflecting ill
-informed over-confidence.
Ian's point wasn't reasonable - what your research shows is that the proble m he referred to wasn't a fundamental problem with wind-turbines, but rathe r a beginner's mistake, reflecting an inadequate appreciation of the loads involved.
An "inadequate appreciation of the loads involved" is another way of saying that the engineers involved didn't do a particularly good job. Saying that is a matter of fact - not "hurling silly insults", which is what you have chosen to do.
-- Bill Sloman, Sydney
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