We believed that we installed enough solar last based year based on our historical usage to cover our consumption. it was recommended that we install the number of panels required to produce 6,2kw. A couple of days ago we had temperatures that exceeeded 40deg. so we put our ducted A/C on and were pretty confident that we would be producing most of the energy required to run it. I have an app that I can monitor what we are producing, what we are consuming and what we are selling to the grid at any point in time. I was surprised to see that we were only producing around 3,4 KWs and we were using around 5kw ie. I was a little perplexed as to why we were not making more so I asked my son who is an electrician and he told me that over a certain temperature solar panels start losing their efficiiency. I googled it and sure enough for every 1 deg. above 28deg. a panel loses .3% which means as the temp was above 40 deg we would have been losing 3.6 % which still didnt equate to being so far under our rated output. We have something like 16 individually controlled panels so does that mean its .3 loss x each deg above 28 x 16 panels = 57 % ie in series or does the whole system just lose 3,6 % because to me it looks like its the first case and thats not good when you are more likely to run your A/C on the hottest days.
I am definately not a solar expert I was just curious about what the app. is actually telling me.
We believed that we installed enough solar last based year based on our historical usage to cover our consumption. it was recommended that we install the number of panels required to produce 6,2kw. A couple of days ago we had temperatures that exceeeded 40deg. so we put our ducted A/C on and were pretty confident that we would be producing most of the energy required to run it. I have an app that I can monitor what we are producing, what we are consuming and what we are selling to the grid at any point in time. I was surprised to see that we were only producing around 3,4 KWs and we were using around 5kw ie. I was a little perplexed as to why we were not making more so I asked my son who is an electrician and he told me that over a certain temperature solar panels start losing their efficiiency. I googled it and sure enough for every 1 deg. above 28deg. a panel loses .3% which means as the temp was above 40 deg we would have been losing 3.6 % which still didnt equate to being so far under our rated output. We have something like 16 individually controlled panels so does that mean its .3 loss x each deg above 28 x 16 panels = 57 % ie in series or does the whole system just lose 3,6 % because to me it looks like its the first case and thats not good when you are more likely to run your A/C on the hottest days.
I am definately not a solar expert I was just curious about what the app. is actually telling me.
BB
It's 3.6% of total produced. Without being unkind I would suggest that like many thousands of people, you've been sold an El Cheapo system, maybe even one of the $4,000 to $6,000 con-job TV specials.What inverter do you have?
When you say "individually controlled panels" are you referring to micro-inverters? Cheers
P.S There is much more I could help you with, but gotta go to work. If you're on single phase you'll have a 5kw inverter. On a good day it may supply a smidgen over 5kw, but to get best out of inverter always there should be more panel capacity. In NSW, from memory, you're allowed 33% more panel capacity than inverter rating.
-- Edited by yobarr on Thursday 14th of December 2023 06:38:15 AM
I have water cooled my 120 watt portable system as a test to see how much one can squeeze out of the panels.
It will produce up to about 125 watts without water with good ventilation. Up to 137 watts with water, on a really good day. But typically into the low 130 watt range with water cooling.
Victron MPPT 100/20 controller & 6awg wiring.
One can get blood out of a stone if you have a quality setup.
__________________
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50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
Yobar we definately didint go with a cheap supplier we went with Solahart who have been doing solar since 1953. if I remember we were out of pocket around $7K even after a pretty generous NSW govt rebate. The system is called a Solarhart Platinum Opimised and it uses Silhouette N Type monocrystaline half cell multui bubsr 415W panels. We paid an extra $1600 to have Solaedge power optimizers that manage each panel individually so if you have a panel performing at less than it should or not working at all the system compensates. Apparently with the cheaper option they are connected in series with one regualtor and if you lose a panel you lose the lot (or so the salesman said). The platinum system includes a SolarEdge Single Phase energy hub inverter designed to work in conjunction with the Power Optimisers on each panel rather than the inverter brand that they use for the cheaper options. There is a 25 year warranty on the system and the panels are rated to slowly degrade in efficiency over the years dropping down to around 84% after 30 years. As I said we have an app. that I can use to montor the systems performance and history inc. instantaneous, daily, monthly, yearly broken down using graphs and schematics into total produced, whats being consumed and whats going to the grid. When we were on our recent around Australia trip I could open the app from anywhere in the country and see what was happening back home with the system. I know all these stats because I just went onto their website and reread the technical specs feel free to check them out there is a lot more info than I put here. By the way if you decide to instal a Solahart system can you please mention my name so I get a $500 gift voucher . Right now at 8am and very overcast the app. is telling me that we are producing .69kW and consuming .28kW with the excess going to the grid.
BB
-- Edited by The Belmont Bear on Thursday 14th of December 2023 08:12:10 AM
-- Edited by The Belmont Bear on Thursday 14th of December 2023 08:14:32 AM
Are the panels spotlessly clean. Amazing how a message from a bird can bring a panel to its knees or verdigris moss build up if panels haven't had a clean for awhile.
A small investment might be worthwhile in a FPV drone for maintenance plan.
__________________
Procrastination, mankind's greatest labour saving device!
50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
The optimal temperature for solar panels is around 25°C (77°F). Solar panels perform best under moderate temperatures, as higher or lower temperatures can reduce efficiency. For every degree above 25°C, a solar panel's output can decrease by around 0.3% to 0.5%, affecting overall energy production. Along with that a solar panel has an efficency 15-22%. I would guess you app would be close to true.
I remember a couple of years back, before I removed most of the solar panel from the caravan, generally the batteries were fully charged by 9am. After that the controller was in floating.
It's not only the Solar Panels that are susceptible to high heat as are Inverters & micro inverters. Also if your Inverter is outside even if under a awning or verandah in heat, such as you are talking about the heat would be greater and the Inverters heat sink would struggle.
.... for every 1 deg. above 28deg. a panel loses .3% which means as the temp was above 40 deg we would have been losing 3.6 % which still didnt equate....
I thought 25 degrees was the standard rating. I believe that will be the temperature of the solar panel, not the ambient temperature. I don't know what temperature a panel would reach on a blazing hot day, but I am guessing maybe 75 degrees for roof mounted panels. Mounted on a frame with air circulation would do better.
So a panel at 75 degrees would be 50 degrees above optimum. 50 x 0.3 = 15%. If the degradation is actually 0.5% as suggested by Gundog, and some sites, that makes 25% reduction in output. If the sun is at an angle then it would be affected as well.
-- Edited by Are We Lost on Thursday 14th of December 2023 10:41:13 AM
Are the panels spotlessly clean. Amazing how a message from a bird can bring a panel to its knees or verdigris moss build up if panels haven't had a clean for awhile.
A small investment might be worthwhile in a FPV drone for maintenance plan.
I dont know if the ones on the house roof are clean because we are on top of a steep block and its 2 storey and I would need a cherry picker to see them. I can see the ones that are on the garage roof which is lower they look reasonably clean maybe a bit of dust on them but according to Solahart rain should be enough to clean them. I dont know if you are supposed to get them serviced ie. checked and cleaned every couple of years there was nothing said about doing that. A drone maybe the answer I will have a look around see if I can find a cheap one.
.... for every 1 deg. above 28deg. a panel loses .3% which means as the temp was above 40 deg we would have been losing 3.6 % which still didnt equate....
I thought 25 degrees was the standard rating. I believe that will be the temperature of the solar panel, not the ambient temperature. I don't know what temperature a panel would reach on a blazing hot day, but I am guessing maybe 75 degrees for roof mounted panels. Mounted on a frame with air circulation would do better.
So a panel at 75 degrees would be 50 degrees above optimum. 50 x 0.3 = 15%. If the degradation is actually 0.5% as suggested by Gundog, and some sites, that makes 25% reduction in output. If the sun is at an angle then it would be affected as well.
-- Edited by Are We Lost on Thursday 14th of December 2023 10:41:13 AM
You are probably correct it may have been 25deg. they quoted on Google for some reason 28deg. stuck in my head.
It's not only the Solar Panels that are susceptible to high heat as are Inverters & micro inverters. Also if your Inverter is outside even if under a awning or verandah in heat, such as you are talking about the heat would be greater and the Inverters heat sink would struggle.
Kebbin the meter box is on the outside brick wall of the garage and the inverter is on the inside of the same wall. The wall also faces north south and it is relatively well shaded so thats probably not an issue .
Controllers will increasing derate themselves as they reach maximum designed operating temperature (unless they are some Chinese third rate cheap stuff that will fail when you are in the Pilbara).
It's why I got a large than needed controller & additionally added extra heatsinks front & back.
Controller with more heatsinks on other side to remove heat where possible on extreme ambient heat days.
(Second controller in foreground for a dual controller test)
Rght now the app is telling we at 12.10pm it is 32deg. with no cloud and we are producing 4.93kW and consuming 1.2kW with the swimming pool filter running. That sounds a lot more reasonable than it was when it was over 40 deg the other day. Fun trivia its also telling me since installation we have produced 13.6 mwh, saved 8,216.2kg in carbon emissions which is the equivalent of planting 159 trees.
Yobar we definately didint go with a cheap supplier we went with Solahart who have been doing solar since 1953. if I remember we were out of pocket around $7K even after a pretty generous NSW govt rebate. The system is called a Solarhart Platinum Opimised and it uses Silhouette N Type monocrystaline half cell multui bubsr 415W panels. We paid an extra $1600 to have Solaedge power optimizers that manage each panel individually so if you have a panel performing at less than it should or not working at all the system compensates. Apparently with the cheaper option they are connected in series with one regualtor and if you lose a panel you lose the lot (or so the salesman said). The platinum system includes a SolarEdge Single Phase energy hub inverter designed to work in conjunction with the Power Optimisers on each panel rather than the inverter brand that they use for the cheaper options. There is a 25 year warranty on the system and the panels are rated to slowly degrade in efficiency over the years dropping down to around 84% after 30 years. As I said we have an app. that I can use to montor the systems performance and history inc. instantaneous, daily, monthly, yearly broken down using graphs and schematics into total produced, whats being consumed and whats going to the grid. When we were on our recent around Australia trip I could open the app from anywhere in the country and see what was happening back home with the system. I know all these stats because I just went onto their website and reread the technical specs feel free to check them out there is a lot more info than I put here. By the way if you decide to instal a Solahart system can you please mention my name so I get a $500 gift voucher . Right now at 8am and very overcast the app. is telling me that we are producing .69kW and consuming .28kW with the excess going to the grid.
BB
Hi Dave. Because I am driving long hours for the next few days I cannot devote much time to this, but after being involved in selling high-quality Solar for some years, you can rest assured that I will not be recommending to anyone that they purchase the products you have bought. Sorry, no $500! Cheers
Yobar we definately didint go with a cheap supplier we went with Solahart who have been doing solar since 1953. if I remember we were out of pocket around $7K even after a pretty generous NSW govt rebate. The system is called a Solarhart Platinum Opimised and it uses Silhouette N Type monocrystaline half cell multui bubsr 415W panels. We paid an extra $1600 to have Solaedge power optimizers that manage each panel individually so if you have a panel performing at less than it should or not working at all the system compensates. Apparently with the cheaper option they are connected in series with one regualtor and if you lose a panel you lose the lot (or so the salesman said). The platinum system includes a SolarEdge Single Phase energy hub inverter designed to work in conjunction with the Power Optimisers on each panel rather than the inverter brand that they use for the cheaper options. There is a 25 year warranty on the system and the panels are rated to slowly degrade in efficiency over the years dropping down to around 84% after 30 years. As I said we have an app. that I can use to montor the systems performance and history inc. instantaneous, daily, monthly, yearly broken down using graphs and schematics into total produced, whats being consumed and whats going to the grid. When we were on our recent around Australia trip I could open the app from anywhere in the country and see what was happening back home with the system. I know all these stats because I just went onto their website and reread the technical specs feel free to check them out there is a lot more info than I put here. By the way if you decide to instal a Solahart system can you please mention my name so I get a $500 gift voucher . Right now at 8am and very overcast the app. is telling me that we are producing .69kW and consuming .28kW with the excess going to the grid.
BB
Hi Dave. Because I am driving long hours for the next few days I cannot devote much time to this, but after being involved in selling high-quality Solar for some years, you can rest assured that I will not be recommending to anyone that they purchase the products you have bought. Sorry, no $500! Cheers
I guess most people like me who had little knowledge about solar relied on recomendations from existing solar customers, onsite assessments, doing research on google and reading quality reviews like Canstar etc. before investing in our system. The Solahart company has been in the solar game since 1953 and was rated highly by Canstar for supplying quality products. I dont know what else people are supposed to do to ensure that they get a quality system. What we bought was definately not cheap at around $11K before govt, rebates it was not one of the el cheapo systems that you often see advertised. Today I monitored the production using the App. at different times during the day ie. at 8am 22deg, and cloudy producing .69kW, 12pm 32deg, clear sky producing 4,9kW, 3pm clear sky 40deg, producing 1.7kW. It would appear that extreme temperature has a pretty big impact on the output hence my original post. Yobar when you have time please go onto the Solahart website and read the technical data for the (Platinum optimised System) ie. panels. inverter, power optimiser management system etc and tell me where we could have done better - I,m sure that a lot of other people contemplating installing solar would also like to know.
. Right now at 8am and very overcast the app. is telling me that we are producing .69kW and consuming .28kW with the excess going to the grid.
