Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
Trading money for hassle. Hassle won. On Tue, Sep 22, 2015 at 9:25 AM, Chuck McCown wrote: > Yeah, their solar panel was a thin film rolled into a tube. They slid > that into a glass tube and injected some kind of oil in between. The > modules were arrays of tubes with a gap between tubes. > > They were better at constant out put, but they were really bad on watts > per square foot and dollars per watt. My son bought truckloads of them > when they went bankrupt. > > *From:* Cameron Crum > *Sent:* Tuesday, September 22, 2015 8:01 AM > *To:* af@afmug.com > *Subject:* Re: [AFMUG] The dreaded annual "how to keep snow and ice off > my solar panels" thread > > Wasn't this sort of Solindra's idea? Tube shaped solar "panels" with a > white reflective surface underneath so that no matter the angle some part > of the panel was always getting light. It took more "tubes" but removed the > hassle of having to worry about angles and time of day. > > > > On Tue, Sep 22, 2015 at 8:23 AM, Chuck McCown wrote: > >> Have you tried inverted panels? >> >> (Most on this list have probably heard this story before.) >> >> I had a mountain top site that lost about half of its power production >> after a big storm. Flew over it and found that one set of panels had come >> loose at the top and flopped over so they were facing the ground at an >> angle. Probably 30 degrees from horizontal. >> >> The snow on the ground was reflecting the sunlight up into the panels and >> they were actually putting out a surprising amount of power. Could always >> count on them being alive the day after the storm. I figured if I ever had >> to do an extreme high reliability site, I would build a white reflector on >> the ground and use inverted panels over it. Have to work on the geometry >> of the reflector and panels but it could be a useful emergency source of >> power in areas where snow and ice cause problems. You normally have the >> clearest skies and brightest sun the day after the storm. >> >> *From:* Steve D >> *Sent:* Monday, September 21, 2015 10:37 PM >> *To:* af >> *Subject:* Re: [AFMUG] The dreaded annual "how to keep snow and ice off >> my solar panels" thread >> >> Vertical panels is something we're experimenting with as well. Started >> ignoring "optimum" angles years ago and pushed the panels as steep as they >> would go with existing hardware (about 80-85) but it's amazing what will >> still stick. Last winter we had a freezing rain that built up ice on the >> bottom metal lip around the glass and the wet sticky snow that followed >> built up 4-5 inches on top of that, even at those angles. (Last year was >> honestly the worst year for our solar sites in the last few years.) >> >> We're in the process of beefing up and extending the angle brackets for >> the racks at two sites so that we can go all the way vertical. I think >> snow will be fine at one of the low elevation sites, but the high elevation >> I still half expect to see them covered in hoar frost. >> >> On Mon, Sep 21, 2015 at 1:17 PM, Eric Kuhnke < >> e...@kuhnke-international.com> wrote: >> >>> If you're off grid and at latitude 35N or higher... The one thing you >>> should care about is cumulative kWh production in December and January. >>> >>> Try putting the panels at an 85 or 90 degree tilt (yes, really) facing >>> due south. You will produce a lot less in June/July but your winter >>> production will be maximized. This also has the effect of ameliorating snow >>> and ice buildup thanks to gravity. >>> >>> The US DoE NREL and other sources have a lot of research on latitude vs. >>> angle tilt of solar panels. Ignore everything intended for gridtie >>> applications and stuff like "tilt the solar panels at the same angle as >>> your latitude". There are some online calculators like pvwatts that will >>> show you your December and January production for a 45 degree tilt vs. an >>> 85 degree tilt. >>> >>> >>> >>> On 9/19/15 11:05 PM, Steve D wrote: >>> >>>> Maybe it's Saturday night exhaustion talking, but piping the exhaust >>>> from a standby generator toward the back of solar panels a bad idea? I'd >>>> expect it to not put heat on the panels in the summer except it's weekly >>>> exercise cycle but that shouldn't be too bad? LP too so shouldn't be any >>>> soot. Or would this just create one little hole of open panel and a pile >>>> of ice? Bad in general for the panels? >>>> >>>> If I did this again, I'd put the damn thing directly under the >>>> panels... these Onan's get stinking hot. My little "cool running", >>>> comparatively speaking, portable yamaha's will melt a two foot radius of >>>> snow around them if they run for a good length of time, all this heat going >>>> to waste! The Onan would probably clear the whole rack if it was sitting >>>> right below it. >>>> >>>> Grumble grumble... snow... something, something, curse words... >>>> >>>> Cheers, >>>> >>>> Steve D >>>> >>>> >>> >> > >
Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
Yeah, their solar panel was a thin film rolled into a tube. They slid that into a glass tube and injected some kind of oil in between. The modules were arrays of tubes with a gap between tubes. They were better at constant out put, but they were really bad on watts per square foot and dollars per watt. My son bought truckloads of them when they went bankrupt. From: Cameron Crum Sent: Tuesday, September 22, 2015 8:01 AM To: af@afmug.com Subject: Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread Wasn't this sort of Solindra's idea? Tube shaped solar "panels" with a white reflective surface underneath so that no matter the angle some part of the panel was always getting light. It took more "tubes" but removed the hassle of having to worry about angles and time of day. On Tue, Sep 22, 2015 at 8:23 AM, Chuck McCown wrote: Have you tried inverted panels? (Most on this list have probably heard this story before.) I had a mountain top site that lost about half of its power production after a big storm. Flew over it and found that one set of panels had come loose at the top and flopped over so they were facing the ground at an angle. Probably 30 degrees from horizontal. The snow on the ground was reflecting the sunlight up into the panels and they were actually putting out a surprising amount of power. Could always count on them being alive the day after the storm. I figured if I ever had to do an extreme high reliability site, I would build a white reflector on the ground and use inverted panels over it. Have to work on the geometry of the reflector and panels but it could be a useful emergency source of power in areas where snow and ice cause problems. You normally have the clearest skies and brightest sun the day after the storm. From: Steve D Sent: Monday, September 21, 2015 10:37 PM To: af Subject: Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread Vertical panels is something we're experimenting with as well. Started ignoring "optimum" angles years ago and pushed the panels as steep as they would go with existing hardware (about 80-85) but it's amazing what will still stick. Last winter we had a freezing rain that built up ice on the bottom metal lip around the glass and the wet sticky snow that followed built up 4-5 inches on top of that, even at those angles. (Last year was honestly the worst year for our solar sites in the last few years.) We're in the process of beefing up and extending the angle brackets for the racks at two sites so that we can go all the way vertical. I think snow will be fine at one of the low elevation sites, but the high elevation I still half expect to see them covered in hoar frost. On Mon, Sep 21, 2015 at 1:17 PM, Eric Kuhnke wrote: If you're off grid and at latitude 35N or higher... The one thing you should care about is cumulative kWh production in December and January. Try putting the panels at an 85 or 90 degree tilt (yes, really) facing due south. You will produce a lot less in June/July but your winter production will be maximized. This also has the effect of ameliorating snow and ice buildup thanks to gravity. The US DoE NREL and other sources have a lot of research on latitude vs. angle tilt of solar panels. Ignore everything intended for gridtie applications and stuff like "tilt the solar panels at the same angle as your latitude". There are some online calculators like pvwatts that will show you your December and January production for a 45 degree tilt vs. an 85 degree tilt. On 9/19/15 11:05 PM, Steve D wrote: Maybe it's Saturday night exhaustion talking, but piping the exhaust from a standby generator toward the back of solar panels a bad idea? I'd expect it to not put heat on the panels in the summer except it's weekly exercise cycle but that shouldn't be too bad? LP too so shouldn't be any soot. Or would this just create one little hole of open panel and a pile of ice? Bad in general for the panels? If I did this again, I'd put the damn thing directly under the panels... these Onan's get stinking hot. My little "cool running", comparatively speaking, portable yamaha's will melt a two foot radius of snow around them if they run for a good length of time, all this heat going to waste! The Onan would probably clear the whole rack if it was sitting right below it. Grumble grumble... snow... something, something, curse words... Cheers, Steve D
Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
Wasn't this sort of Solindra's idea? Tube shaped solar "panels" with a white reflective surface underneath so that no matter the angle some part of the panel was always getting light. It took more "tubes" but removed the hassle of having to worry about angles and time of day. On Tue, Sep 22, 2015 at 8:23 AM, Chuck McCown wrote: > Have you tried inverted panels? > > (Most on this list have probably heard this story before.) > > I had a mountain top site that lost about half of its power production > after a big storm. Flew over it and found that one set of panels had come > loose at the top and flopped over so they were facing the ground at an > angle. Probably 30 degrees from horizontal. > > The snow on the ground was reflecting the sunlight up into the panels and > they were actually putting out a surprising amount of power. Could always > count on them being alive the day after the storm. I figured if I ever had > to do an extreme high reliability site, I would build a white reflector on > the ground and use inverted panels over it. Have to work on the geometry > of the reflector and panels but it could be a useful emergency source of > power in areas where snow and ice cause problems. You normally have the > clearest skies and brightest sun the day after the storm. > > *From:* Steve D > *Sent:* Monday, September 21, 2015 10:37 PM > *To:* af > *Subject:* Re: [AFMUG] The dreaded annual "how to keep snow and ice off > my solar panels" thread > > Vertical panels is something we're experimenting with as well. Started > ignoring "optimum" angles years ago and pushed the panels as steep as they > would go with existing hardware (about 80-85) but it's amazing what will > still stick. Last winter we had a freezing rain that built up ice on the > bottom metal lip around the glass and the wet sticky snow that followed > built up 4-5 inches on top of that, even at those angles. (Last year was > honestly the worst year for our solar sites in the last few years.) > > We're in the process of beefing up and extending the angle brackets for > the racks at two sites so that we can go all the way vertical. I think > snow will be fine at one of the low elevation sites, but the high elevation > I still half expect to see them covered in hoar frost. > > On Mon, Sep 21, 2015 at 1:17 PM, Eric Kuhnke < > e...@kuhnke-international.com> wrote: > >> If you're off grid and at latitude 35N or higher... The one thing you >> should care about is cumulative kWh production in December and January. >> >> Try putting the panels at an 85 or 90 degree tilt (yes, really) facing >> due south. You will produce a lot less in June/July but your winter >> production will be maximized. This also has the effect of ameliorating snow >> and ice buildup thanks to gravity. >> >> The US DoE NREL and other sources have a lot of research on latitude vs. >> angle tilt of solar panels. Ignore everything intended for gridtie >> applications and stuff like "tilt the solar panels at the same angle as >> your latitude". There are some online calculators like pvwatts that will >> show you your December and January production for a 45 degree tilt vs. an >> 85 degree tilt. >> >> >> >> On 9/19/15 11:05 PM, Steve D wrote: >> >>> Maybe it's Saturday night exhaustion talking, but piping the exhaust >>> from a standby generator toward the back of solar panels a bad idea? I'd >>> expect it to not put heat on the panels in the summer except it's weekly >>> exercise cycle but that shouldn't be too bad? LP too so shouldn't be any >>> soot. Or would this just create one little hole of open panel and a pile >>> of ice? Bad in general for the panels? >>> >>> If I did this again, I'd put the damn thing directly under the panels... >>> these Onan's get stinking hot. My little "cool running", comparatively >>> speaking, portable yamaha's will melt a two foot radius of snow around them >>> if they run for a good length of time, all this heat going to waste! The >>> Onan would probably clear the whole rack if it was sitting right below it. >>> >>> Grumble grumble... snow... something, something, curse words... >>> >>> Cheers, >>> >>> Steve D >>> >>> >> >
Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
Have you tried inverted panels? (Most on this list have probably heard this story before.) I had a mountain top site that lost about half of its power production after a big storm. Flew over it and found that one set of panels had come loose at the top and flopped over so they were facing the ground at an angle. Probably 30 degrees from horizontal. The snow on the ground was reflecting the sunlight up into the panels and they were actually putting out a surprising amount of power. Could always count on them being alive the day after the storm. I figured if I ever had to do an extreme high reliability site, I would build a white reflector on the ground and use inverted panels over it. Have to work on the geometry of the reflector and panels but it could be a useful emergency source of power in areas where snow and ice cause problems. You normally have the clearest skies and brightest sun the day after the storm. From: Steve D Sent: Monday, September 21, 2015 10:37 PM To: af Subject: Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread Vertical panels is something we're experimenting with as well. Started ignoring "optimum" angles years ago and pushed the panels as steep as they would go with existing hardware (about 80-85) but it's amazing what will still stick. Last winter we had a freezing rain that built up ice on the bottom metal lip around the glass and the wet sticky snow that followed built up 4-5 inches on top of that, even at those angles. (Last year was honestly the worst year for our solar sites in the last few years.) We're in the process of beefing up and extending the angle brackets for the racks at two sites so that we can go all the way vertical. I think snow will be fine at one of the low elevation sites, but the high elevation I still half expect to see them covered in hoar frost. On Mon, Sep 21, 2015 at 1:17 PM, Eric Kuhnke wrote: If you're off grid and at latitude 35N or higher... The one thing you should care about is cumulative kWh production in December and January. Try putting the panels at an 85 or 90 degree tilt (yes, really) facing due south. You will produce a lot less in June/July but your winter production will be maximized. This also has the effect of ameliorating snow and ice buildup thanks to gravity. The US DoE NREL and other sources have a lot of research on latitude vs. angle tilt of solar panels. Ignore everything intended for gridtie applications and stuff like "tilt the solar panels at the same angle as your latitude". There are some online calculators like pvwatts that will show you your December and January production for a 45 degree tilt vs. an 85 degree tilt. On 9/19/15 11:05 PM, Steve D wrote: Maybe it's Saturday night exhaustion talking, but piping the exhaust from a standby generator toward the back of solar panels a bad idea? I'd expect it to not put heat on the panels in the summer except it's weekly exercise cycle but that shouldn't be too bad? LP too so shouldn't be any soot. Or would this just create one little hole of open panel and a pile of ice? Bad in general for the panels? If I did this again, I'd put the damn thing directly under the panels... these Onan's get stinking hot. My little "cool running", comparatively speaking, portable yamaha's will melt a two foot radius of snow around them if they run for a good length of time, all this heat going to waste! The Onan would probably clear the whole rack if it was sitting right below it. Grumble grumble... snow... something, something, curse words... Cheers, Steve D
Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
Vertical panels is something we're experimenting with as well. Started ignoring "optimum" angles years ago and pushed the panels as steep as they would go with existing hardware (about 80-85) but it's amazing what will still stick. Last winter we had a freezing rain that built up ice on the bottom metal lip around the glass and the wet sticky snow that followed built up 4-5 inches on top of that, even at those angles. (Last year was honestly the worst year for our solar sites in the last few years.) We're in the process of beefing up and extending the angle brackets for the racks at two sites so that we can go all the way vertical. I think snow will be fine at one of the low elevation sites, but the high elevation I still half expect to see them covered in hoar frost. On Mon, Sep 21, 2015 at 1:17 PM, Eric Kuhnke wrote: > If you're off grid and at latitude 35N or higher... The one thing you > should care about is cumulative kWh production in December and January. > > Try putting the panels at an 85 or 90 degree tilt (yes, really) facing due > south. You will produce a lot less in June/July but your winter production > will be maximized. This also has the effect of ameliorating snow and ice > buildup thanks to gravity. > > The US DoE NREL and other sources have a lot of research on latitude vs. > angle tilt of solar panels. Ignore everything intended for gridtie > applications and stuff like "tilt the solar panels at the same angle as > your latitude". There are some online calculators like pvwatts that will > show you your December and January production for a 45 degree tilt vs. an > 85 degree tilt. > > > > On 9/19/15 11:05 PM, Steve D wrote: > >> Maybe it's Saturday night exhaustion talking, but piping the exhaust from >> a standby generator toward the back of solar panels a bad idea? I'd expect >> it to not put heat on the panels in the summer except it's weekly exercise >> cycle but that shouldn't be too bad? LP too so shouldn't be any soot. Or >> would this just create one little hole of open panel and a pile of ice? >> Bad in general for the panels? >> >> If I did this again, I'd put the damn thing directly under the panels... >> these Onan's get stinking hot. My little "cool running", comparatively >> speaking, portable yamaha's will melt a two foot radius of snow around them >> if they run for a good length of time, all this heat going to waste! The >> Onan would probably clear the whole rack if it was sitting right below it. >> >> Grumble grumble... snow... something, something, curse words... >> >> Cheers, >> >> Steve D >> >> >
Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
If you're off grid and at latitude 35N or higher... The one thing you should care about is cumulative kWh production in December and January. Try putting the panels at an 85 or 90 degree tilt (yes, really) facing due south. You will produce a lot less in June/July but your winter production will be maximized. This also has the effect of ameliorating snow and ice buildup thanks to gravity. The US DoE NREL and other sources have a lot of research on latitude vs. angle tilt of solar panels. Ignore everything intended for gridtie applications and stuff like "tilt the solar panels at the same angle as your latitude". There are some online calculators like pvwatts that will show you your December and January production for a 45 degree tilt vs. an 85 degree tilt. On Sat, Sep 19, 2015 at 11:05 PM, Steve D wrote: > Maybe it's Saturday night exhaustion talking, but piping the exhaust from > a standby generator toward the back of solar panels a bad idea? I'd expect > it to not put heat on the panels in the summer except it's weekly exercise > cycle but that shouldn't be too bad? LP too so shouldn't be any soot. Or > would this just create one little hole of open panel and a pile of ice? > Bad in general for the panels? > > If I did this again, I'd put the damn thing directly under the panels... > these Onan's get stinking hot. My little "cool running", comparatively > speaking, portable yamaha's will melt a two foot radius of snow around them > if they run for a good length of time, all this heat going to waste! The > Onan would probably clear the whole rack if it was sitting right below it. > > Grumble grumble... snow... something, something, curse words... > > Cheers, > > Steve D > >
Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
If you're off grid and at latitude 35N or higher... The one thing you should care about is cumulative kWh production in December and January. Try putting the panels at an 85 or 90 degree tilt (yes, really) facing due south. You will produce a lot less in June/July but your winter production will be maximized. This also has the effect of ameliorating snow and ice buildup thanks to gravity. The US DoE NREL and other sources have a lot of research on latitude vs. angle tilt of solar panels. Ignore everything intended for gridtie applications and stuff like "tilt the solar panels at the same angle as your latitude". There are some online calculators like pvwatts that will show you your December and January production for a 45 degree tilt vs. an 85 degree tilt. On 9/19/15 11:05 PM, Steve D wrote: Maybe it's Saturday night exhaustion talking, but piping the exhaust from a standby generator toward the back of solar panels a bad idea? I'd expect it to not put heat on the panels in the summer except it's weekly exercise cycle but that shouldn't be too bad? LP too so shouldn't be any soot. Or would this just create one little hole of open panel and a pile of ice? Bad in general for the panels? If I did this again, I'd put the damn thing directly under the panels... these Onan's get stinking hot. My little "cool running", comparatively speaking, portable yamaha's will melt a two foot radius of snow around them if they run for a good length of time, all this heat going to waste! The Onan would probably clear the whole rack if it was sitting right below it. Grumble grumble... snow... something, something, curse words... Cheers, Steve D
Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
+1000 on the frothpack. We applied it (per chucks recommendation) several years ago and it made a huge difference!!! Like I said earlier too, I'd highly recommend applying rainx which makes the panels slick. Between that and the extra heating from the insulation our panels produce a significantly greater amount of electricity. FYI we are in NW CO and we typically get 350-500 inches of snow per winter. (~30-40 feet!) it typically snows everyday of December and most of jan & feb. we have 4 solar sites with propane generator backup (we have 1 week battery banks, but that much snow requires generator backup) 2 cents -Sean On Sunday, September 20, 2015, Chuck McCown wrote: > Yeah, the antifreeze system was a bit spendy. We used an electric hot > water heater tank due the fact it has a tube that goes to the bottom. Used > a CO2 tank from a soda machine. > > I had some photos of insulated and non insulated side by side. It was > fairly dramatic when full sun came out on fresh snow. Snow was all off the > insulated panels by 10 am and the non insulate still had some snow in them > when the sun went down. > > I am of the opinion that you have to ensure there is no air gap between > the insulation and the backs of the panels. > > Spray foam can be purchased in “froth pak” kits. It is not messy. Very > easy to apply. Two tanks that look like freon tanks. They feed into a > disposable gun. They give you a few disposable nozzles because once you > start spraying, the nozzle is good until you stop. The chemicals mix in > the nozzle and it plugs up in seconds after stopping spraying. > > *From:* Steve D > *Sent:* Sunday, September 20, 2015 1:55 PM > *To:* af > *Subject:* Re: [AFMUG] The dreaded annual "how to keep snow and ice off > my solarpanels" thread > > Anyone got any pics of insulated panels side by side with uninsulated > panels? We tried taping a piece of styrofoam to the back of one once, but > it never seemed to make enough of a difference (especially for the hoar > frost that plagues our mountain tops). Bosses aren't convinced the mess of > sprayfoam would be worthwhile. > > I enjoyed reading your testing with the different sprayers Chuck. The > antifreeze was fairly expensive though if I recall? > > -Steve D > > On Sun, Sep 20, 2015 at 11:36 AM, Chuck McCown > wrote: > >> I did lots of experiments about 15 years ago adding heat to panels with >> various methods. Heat tape, hot air blowers, exhaust, all kinds of ideas >> were worked on. >> >> I came up with two things that work. First, lots of insulation on the >> backs. Spray foam worked extra good. It helps to speed up snow/ice >> sliding/melting off when the sun comes out. >> >> Second thing that works is the application of antifreeze. Propylene >> glycol is environmentally safe for the wildlife. Sprayer at the top works >> pretty good. We rigged up one tank that was pressurized with air and had >> solenoid valve that was turned on via telemetry. Takes almost no energy to >> pump. Did CO2 pressurization too but that will carbonate the antifreeze >> and it doesn’t spray as well. >> >> You can vent the tank and have it drain back if you want. I also tried a >> deicing product made from beet juice. It didn’t work too well. Plugged up >> the spray nozzle. >> >> *From:* Steve D >> *Sent:* Sunday, September 20, 2015 12:05 AM >> *To:* af >> *Subject:* [AFMUG] The dreaded annual "how to keep snow and ice off my >> solarpanels" thread >> >> Maybe it's Saturday night exhaustion talking, but piping the exhaust from >> a standby generator toward the back of solar panels a bad idea? I'd expect >> it to not put heat on the panels in the summer except it's weekly exercise >> cycle but that shouldn't be too bad? LP too so shouldn't be any soot. Or >> would this just create one little hole of open panel and a pile of ice? >> Bad in general for the panels? >> >> If I did this again, I'd put the damn thing directly under the panels... >> these Onan's get stinking hot. My little "cool running", comparatively >> speaking, portable yamaha's will melt a two foot radius of snow around them >> if they run for a good length of time, all this heat going to waste! The >> Onan would probably clear the whole rack if it was sitting right below it. >> >> Grumble grumble... snow... something, something, curse words... >> >> Cheers, >> >> Steve D >> >> > >
Re: [AFMUG] The dreaded annual "how to keep snow and ice off my solar panels" thread
We spray foam insulation on the back of our panels and it works great. Once you get even a slight amount of sunlight even if it's -20 out the snow and ice will slide right off. We also apply rainx to the panels to make them more slick. -Sean On Sunday, September 20, 2015, Steve D wrote: > Maybe it's Saturday night exhaustion talking, but piping the exhaust from > a standby generator toward the back of solar panels a bad idea? I'd expect > it to not put heat on the panels in the summer except it's weekly exercise > cycle but that shouldn't be too bad? LP too so shouldn't be any soot. Or > would this just create one little hole of open panel and a pile of ice? > Bad in general for the panels? > > If I did this again, I'd put the damn thing directly under the panels... > these Onan's get stinking hot. My little "cool running", comparatively > speaking, portable yamaha's will melt a two foot radius of snow around them > if they run for a good length of time, all this heat going to waste! The > Onan would probably clear the whole rack if it was sitting right below it. > > Grumble grumble... snow... something, something, curse words... > > Cheers, > > Steve D > >
