# Solar Panels and Snow Coverage **URL:** \ **Category:** Factual Questions\ **Created:** [November 13, 2010, 5:27pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567 "2010-11-13T17:27:18Z")\ **Posts on this page:** 15\ **Page:** 2
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 14, 2010, 4:10pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/21 "2010-11-14T16:10:28Z")
> [@dtilque](#): > > Arizona may not be any better when all factors are considered. Solar cells are heat sensitive, and lose much of their generating ability when they get too hot. You will get better generation in winter, but lose it in summer. Especially if they are mounted on the roof, which gets hotter than open air places. That’s absurd. The worst-case decrease in efficiency is something like 25%, while the amount of insolation is at least 40% greater in Arizona than Montana: [http://www.solarpower2day.net/images/6.jpg](http://www.solarpower2day.net/images/6.jpg) ---
**Author:** ![R.P.McMurphy](https://avatars.discourse-cdn.com/v4/letter/r/7993a0/32.png) [@R.P.McMurphy](https://boards.straightdope.com/u/R.P.McMurphy)\ **Post date:** [November 14, 2010, 5:44pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/22 "2010-11-14T17:44:51Z")
From experience: If the panels are mounted flat a few inches of snow will effectively shut down electrical production. If the panels are at an angle much of the snow sill not stick and although capacity may be reduced, they will generate power. Any snow that does accumulate on a slanted panel will melt quicker. The fact that the panel is dark helps in that regard. I have some flat panels and last winter for about 2 months they generated just about nothing. The electric bill went way up. After the thaw everything was fine. I was in contact with the solar installation company and inquired about a system to melt the snow. Their answer, which I’m not fully willing to accept, is that there is no such system. I have melting wires in my gutters, I don’t know why something can’t be installed to keep the snow clear. If anyone knows of a solution post it here or PM me. I’ve even thought that maybe a small windmill would generate enough to power the melting wires. I have the feeling that the solar installation company doesn’t want to bother with me. Most solar systems just supplement buildings that are hooked into the grid. The solar panels aren’t the only source of electricity but they significantly reduce consumption from the grid and at times add to it. So what if my panels don’t work for two months? They work great the other 10 months and my energy costs are very low. I have a geothermal system that uses electric heat pumps so I’m burning no oil. That’s a good thing! I get heat in the winter, air conditioning in the summer, continually filtered air and very low energy costs. ---
**Author:** ![constanze](https://avatars.discourse-cdn.com/v4/letter/c/f9ae1b/32.png) [@constanze](https://boards.straightdope.com/u/constanze)\ **Post date:** [November 14, 2010, 6:06pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/23 "2010-11-14T18:06:56Z")
> [@Hari\_Seldon](#): > > Really? The times I have been in Germany (in late spring through early fall) I got the impression that they didn’t have very many sunny days. Lots of overcast and rain. Which part of Germany? The southern states have 8hr+ sunny days on average, and that’s where most of the PV plates are. Plus, even on an overcast day 70% of UV-light gets through, and with the newer cells, you can use quite a bit of that, too. > [@](#): > > When I go to Barbados for two or three weeks every February, I see no solar panels (though the sun gets to about 65 degrees above the horizon in February), but essentially all hot water is generated in rooftops solar tanks. They are ubiquitous and, I assume, not awfully expensive since even the poorest looking houses seem to have them. One question is not only the efficency of PV itself, but the initial investment. If that is too high - several ten thousand Euros, and no special credits to help - than despite excellent sun conditions people in poor areas won’t be able to afford them, and simply put up cheap plastic tanks painted black to warm water. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [November 14, 2010, 6:12pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/24 "2010-11-14T18:12:29Z")
> [@R.P.McMurphy](#): > > If the panels are mounted flat a few inches of snow will effectively shut down electrical production. If the panels are at an angle much of the snow sill not stick and although capacity may be reduced, they will generate power. Any snow that does accumulate on a slanted panel will melt quicker. The fact that the panel is dark helps in that regard. > > I have some flat panels and last winter for about 2 months they generated just about nothing. The electric bill went way up. After the thaw everything was fine. you have photovoltaic panels that are mounted horizontal? ---
**Author:** ![constanze](https://avatars.discourse-cdn.com/v4/letter/c/f9ae1b/32.png) [@constanze](https://boards.straightdope.com/u/constanze)\ **Post date:** [November 14, 2010, 6:38pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/25 "2010-11-14T18:38:03Z")
> [@wmfellows](#): > > I would suggest digging a bit deeper. Germany has such a large market because of rather ill-considered public promotion of PV panels (taxes and rebates). As an economic investment, for most of Germany it makes little sense. Wind, other renewables, fine, solar… Green-eyed bollocks. That is an opinion, not a fact, and wrong. Germany has a lot of solar panels - both PV and thermic - in southern states (Bavaria and Baden-Württemberg) because there’s a lot of solar energy there. This (Big, German) [PDF](http://www.greencity-energy.de/images/stories/PDFs/sp_deutschland_2010_werbeprospekt.pdf) has a graphic from the German Weather Service (DWD) on page 7 (Seite 12, double pages) that shows the amount of solar power. Solar makes sense in Germany for two reasons: high electricity costs mean a lot of money saved; special credits and fixed paybacks (from the power companies) through the government makes the investment more affordable. This investment has lead not only to reduced running costs for numerable small-homes owners, but also to investment opportunities for eco-minded people, and, because of this high demand, to increased research and development of a lot of specialist jobs in mid-size companies who build solar cells, and expert jobs for plumbers and electricians who install solar. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [November 14, 2010, 6:53pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/26 "2010-11-14T18:53:23Z")
> [@constanze](#): > > That is an opinion… > > This investment has lead not only to reduced running costs for numerable small-homes owners, but also to investment opportunities for eco-minded people, and, because of this high demand, to increased research and development of a lot of specialist jobs in mid-size companies who build solar cells, and expert jobs for plumbers and electricians who install solar. [opinion] In this country it seems that many people see the ‘green energy movement’ as a boondoggle. They forget that people need to build the solar units, which means jobs and revenue. (I think there are places here in Washington State that has great potential manufacturing PV panels using locally-sourced materials, and others who are building smaller wind turbines.) And people forget about those plumbers and electricians you mentioned. Aside from the plumbers, electricians, and manufacturers, there is also work for carpenters, roofers, and other contractors. I think that investing in ‘green energy’ will provide many jobs. If carried out in a big way, with a large number of households generating their own energy, demand from existing power plants will be reduced, and perhaps some hydro plants could be dismantled – which would provide jobs for demolition crews, and increase the salmon populations, which would benefit the fishing industry. [/opinion] I would install PV panels, and possibly a wind turbine, if they weren’t so damned expensive. Even with subsidies, such things are not in the budget. I do plan to have some passive lighting installed, though. ([Solatubes](http://www.houseneeds.com/shop/vent/solartube/solastarskylights.asp).) My house was built in 1934 and has been added to a couple/few times over the decades. It’s pretty dark in here. A Solatube in the (windowless) bathroom, one in the (now-windowless) kitchen, and one in the living room would go far toward reducing energy use and brighten the place up. ---
**Author:** ![constanze](https://avatars.discourse-cdn.com/v4/letter/c/f9ae1b/32.png) [@constanze](https://boards.straightdope.com/u/constanze)\ **Post date:** [November 14, 2010, 7:03pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/27 "2010-11-14T19:03:45Z")
> [@johnpost](#): > > you have photovoltaic panels that are mounted horizontal? I assume he means with a low inclination of 5 degrees or so. On totally flat roofs, you usually use stands to mount the panels onto, although you don’t make them to high, because then the wind gets underneath and could rip them off. On a slightly inclined saddle-roof, say 10 degrees, it can be difficult to put stands, so you mount the panels onto the roof, with a low inclination. ---
**Author:** ![R.P.McMurphy](https://avatars.discourse-cdn.com/v4/letter/r/7993a0/32.png) [@R.P.McMurphy](https://boards.straightdope.com/u/R.P.McMurphy)\ **Post date:** [November 14, 2010, 10:32pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/28 "2010-11-14T22:32:01Z")
> [@johnpost](#): > > you have photovoltaic panels that are mounted horizontal? They are mounted on a flat roof. It is the same mounting system that is used in many commercial applications. The decision was made to do it that way for aesthetic reasons. ---
**Author:** ![wmfellows](https://avatars.discourse-cdn.com/v4/letter/w/c2a13f/32.png) [@wmfellows](https://boards.straightdope.com/u/wmfellows)\ **Post date:** [November 14, 2010, 11:49pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/29 "2010-11-14T23:49:46Z")
> [@constanze](#): > > That is an opinion, not a fact, and wrong. It is a fact, and your Green link is boring. > [@](#): > > Germany has a lot of solar panels Yes, it does, because of government programs that promote such, not because it is particularly efficient. > [@](#): > > in southern states (Bavaria and Baden-Württemberg) because there’s a lot of solar energy there. This is so benighted it’s laughable. I suppose there is a lot of solar energy as compared to Bremen, and for pale skinned Germans that is a lot, but by any objective measure the best Southern Germany does is as good as Paris, that well known sunny vacation spot… (that is irony for the irony impaired). You may peruse this map [File:EU-Glob opta presentation.png - Wikipedia](http://en.wikipedia.org/wiki/File:EU-Glob_opta_presentation.png) or review this [http://www.menarec.org/resources/SherifWMSolarCairo2007\_Part2.pdf](http://www.menarec.org/resources/SherifWMSolarCairo2007_Part2.pdf) to see what “a lot of solar energy” actually means in a proper sense. > [@](#): > > Solar makes sense in Germany for two reasons: high electricity costs mean a lot of money saved; special credits and fixed paybacks (from the power companies) through the government makes the investment more affordable. Shrug. Aware the Germans have convinced themselves of this - however high electrical costs are driven by taxation and special programmes, etc., and solar panels in poorly insolated areas is more expensive. The rube goldberg incentive system makes Germans feel Green, bloody far from being the economically rational green power choice however. But fuzzy headed economically illiterate Green Leftism is the main driver. > [@Johnny\_L.A](#): > > [opinion] In this country it seems that many people see the ‘green energy movement’ as a boondoggle. I am not an American mate, got nothing to do with your country’s bizarre head-in-the-sand behaviour re green energy. I do know my numbers however and prefer my green investments to be economically rationale for long-term prosperity. (edited to add": also see this [ams.confex.com/ams/pdfpapers/133178.pdf](http://ams.confex.com/ams/pdfpapers/133178.pdf) ---
**Author:** ![wmfellows](https://avatars.discourse-cdn.com/v4/letter/w/c2a13f/32.png) [@wmfellows](https://boards.straightdope.com/u/wmfellows)\ **Post date:** [November 15, 2010, 12:00am UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/30 "2010-11-15T00:00:44Z")
It is worth adding to avoid a hijack that a debate over the utility of German or North European promotion of PV solar energy in domestic markets belongs elsewhere. I was simply responding to the idea the suggestion that large numbers of PV installed in Germany mean that winter / high latitude reduction of sunlight to the surface does not significantly impact production. ---
**Author:** ![FasterThanMeerkats](https://avatars.discourse-cdn.com/v4/letter/f/278dde/32.png) [@FasterThanMeerkats](https://boards.straightdope.com/u/FasterThanMeerkats)\ **Post date:** [November 15, 2010, 2:57pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/31 "2010-11-15T14:57:03Z")
> [@wmfellows](#): > > I do know my numbers however and prefer my green investments to be economically rationale for long-term prosperity. Have to agree with WM here. There’s an important distinction to be made between what’s best economically for the country, power company, and individual. From a country sense, the analysis is easy. You line up the all-in cost of fuel, O&M, and capital for each generating source, normalize it for plant lives, etc. and stack it up. Solar usually does verrrrrrrrry poorly. From a company sense, you do the same analysis, but factor in government rebates like RECs, accelerated deprecation, etc. Solar still does verrrrrrrry poorly unless you have high power prices. This is why you don’t see huge solar farms everywhere in the U.S. or power companies putting solar on every single roof. From an individual sense, you look at your power rate (in the U.S. 7-20 cents/kwh), compute the cost of solar installation after all government tax credits and REC sales, and look at the difference. Solar makes sense sometimes when the government (i.e. taxpayers) are picking up up most of the installation tab. It’s about resource allocation. Economics suggest one outcome, but governments alter (for whatever reason) the analysis of individual segments by having everyone else foot the bill. I’m not saying it won’t make better sense in the future, but for now…meh. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [November 15, 2010, 3:35pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/32 "2010-11-15T15:35:00Z")
solar electric also makes sense where the cost of bringing the grid to you is large. utilities charge a lot of money to extend their lines. this for the developed world. solar electric and other methods are useful to governments and utilities to promote to prompt exploration into new sources which will be needed in the future. ---
**Author:** ![dolphinboy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dolphinboy/32/330_2.png) [@dolphinboy](https://boards.straightdope.com/u/dolphinboy)\ **Post date:** [November 15, 2010, 5:02pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/33 "2010-11-15T17:02:27Z")
Thanks everybody. Right now electricity is relatively cheap for me (we use hydro in my area) so solar panels don’t make much sense financially, but as electricity rates increase, which they have a tendency to do, at some point it may make sense to look at somehow supplementing the grid, as opposed to getting off of it completely. However, it sounds like I can’t generate much power in the winter for a number of reasons, which is what I had assumed. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [November 15, 2010, 5:35pm UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/34 "2010-11-15T17:35:07Z")
if you were able to remount your panels at a better collection angle or a self cleaning angle then you will get an improvement. people do improve their mounts, even a panel or three at a time, as they can. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [November 16, 2010, 6:01am UTC](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567/35 "2010-11-16T06:01:54Z")
> [@beowulff](#): > > That’s absurd. > The worst-case decrease in efficiency is something like 25%, while the amount of insolation is at least 40% greater in Arizona than Montana: [http://www.solarpower2day.net/images/6.jpg](http://www.solarpower2day.net/images/6.jpg) Maybe you’re right. Somewhere (and I don’t remember where) I got the idea that solar cells just stopped generating power at temperatures typically found in the Arizona summer (somewhere around 120 degrees or so). [Previous page](https://boards.straightdope.com/t/solar-panels-and-snow-coverage/560567.md?page=1)