Poll

Do you keep records of your solar production

No I dont have solar
31 (57.4%)
No I don't care
5 (9.3%)
I look at the GTI LCD occasionally
6 (11.1%)
I look at the GTI display often
4 (7.4%)
I look at the GTI display even after dark
4 (7.4%)
I have solar, no GTI and I keep records (like Mike)
4 (7.4%)

Total Members Voted: 51

Author Topic: UK solar doldrums  (Read 56842 times)

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Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #125 on: January 31, 2018, 07:51:37 pm »
to work out if my system is consuming more internally than it's actually producing
I have two things powered by the grid in the solar system (running 24/7), one is the data logger and the other is the grid import/export power measurer and together they consume 1100mW.

I am guilty of using lots of cheap USB power supplies around the house for powering gadgets and most of them consume >500mW each with no load :( One day I might install a low power low voltage buss (say 12) just for the gadgets! I used to have some guided missile wire (almost invisable) that would have been ideal but it vanished completely in various house moves  :-DD
 

Online nfmax

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Re: UK solar doldrums
« Reply #126 on: February 07, 2018, 08:42:58 pm »
3.842 kWh today! The sun is coming back!  :)
 

Offline paulca

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Re: UK solar doldrums
« Reply #127 on: February 07, 2018, 09:15:35 pm »
Nothing today.  Anything I did get got used by the charge controller :(  Doesn't look like we will get sun until Friday and even then it's a few hours.  My panel only produces a decent amount between 10am and 1pm.  The joys of having a panel in a window.

Still, it's meeting demands for charging USB devices, running my bench supply and running my headphone amp.  Basically anything I can run off 12V battery on my desk.  I can even run a 3W LED lightbulb or two when I feel like it.

I call it NanoGen.
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Online nfmax

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Re: UK solar doldrums
« Reply #128 on: February 16, 2018, 08:31:26 pm »
3.898 kWh today
 

Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #129 on: February 17, 2018, 07:09:30 am »
3.898 kWh today
Yeyy the sun is coming back, my average weekly finally hit 1Kwh/day after a winter low of 0.3Kwh/day from a 1Kwe array. How many Kwe is yours, 4 ?
 

Offline paulca

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Re: UK solar doldrums
« Reply #130 on: February 17, 2018, 09:27:03 am »
I also got a load this week.  All my batteries are topped up.  Each evening I end up running the battery down to 12.1 or 12.2 and come home to it up at 12.6 or 12.7. I might let it fully charge some day, but I expect in summer that will easy.

So far I've hit a peak, from a 50W panel, of 28W.  For a panel behind a window this has to be good.
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Online nfmax

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Re: UK solar doldrums
« Reply #131 on: February 17, 2018, 01:50:55 pm »
3.898 kWh today
Yeyy the sun is coming back, my average weekly finally hit 1Kwh/day after a winter low of 0.3Kwh/day from a 1Kwe array. How many Kwe is yours, 4 ?
1.71 kWp, according to the installation certificate.
 

Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #132 on: February 17, 2018, 04:26:25 pm »
Wowww thats a really good result. Mine is 1060We/p but at this time of year I am not able to use all of a good day as the boiler is still heating the water a bit due to central heating and I don't use enough electricity! Tried today by shredding loads of compost and using the hedge trimmer :)
 

Offline paulca

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Re: UK solar doldrums
« Reply #133 on: February 17, 2018, 04:48:33 pm »
Solar energy storage is the future.  I wonder if micro-hydro works if you don't like batteries.  Probably not :)
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Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #134 on: February 17, 2018, 04:55:11 pm »
Solar energy storage is the future.  I wonder if micro-hydro works if you don't like batteries.  Probably not :)
Hey cool idea, I actually have a stream with almost zero fall/head, I could build a pond further up the garden but I think the frost will be a problem as well as a dual purpose pump/turbine! Never mind I continue to use the grid as my battery! To me it's all about contribution, like that retailer slogan "every little helps" :)
 

Online nfmax

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Re: UK solar doldrums
« Reply #135 on: February 23, 2018, 05:31:11 pm »
And a whopping 5.264 kWh today! Cold, sunny & cloudless
 

Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #136 on: February 23, 2018, 08:19:18 pm »
Wowww well done, weather not so good here so just 0.8Kwh today  :-[ but over 2Kwh couple of days ago :)
 

Online nfmax

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Re: UK solar doldrums
« Reply #137 on: February 24, 2018, 05:49:13 pm »
Today we got 5.396 kWh. One more sunny day forecast, then cloud & possible snow
 

Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #138 on: February 24, 2018, 06:21:37 pm »
1.9Kwh today on a 1Kw array, still held back by terrible Fronious software, drops out all the time and has 5 minute restart delay but hey it will be in the bin soon I hope :) so most of my load is water heating atm. Your figures really are very good sure your really in the UK hahaha
 

Offline paulca

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Re: UK solar doldrums
« Reply #139 on: February 24, 2018, 09:11:49 pm »
I need to move house and get better panels.

Today I started with 12.0V on the battery and ended with 11.9V.  Took more to run the charge controller and 485 Wifi monitor than I actually got from the sun.  It was a pretty dark and miserably day though.
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Offline John Heath

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Re: UK solar doldrums
« Reply #140 on: February 25, 2018, 08:22:32 am »
 I have a solar power system. It is home brew with a 2 by 2 inch solar cell and a nicad power storage capacity of 200 ma at 1.2 volts. This power is automatically used at night to light a single white IR type white LED , 1 volt 20 ma. The reason was to back light an outside temperature gauge so it can be seen at night. All went well for the winter with 3 to 4 hours of a solar powered back lighting. However in the summer the LED attracted small flies. This did not escape the attention of the local spiders who soon set up camp on my solar power system. Not sure what they did but the white LED no longer shines at night. Easier to build another as all the part are in a 4 dollar back yard garden light sold in most stores. I guess my point is even micro solar power systems have their problems. The best laid plans...
 

Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #141 on: February 25, 2018, 09:25:43 am »
I need to move house and get better panels.

Today I started with 12.0V on the battery and ended with 11.9V.  Took more to run the charge controller and 485 Wifi monitor than I actually got from the sun.  It was a pretty dark and miserably day though.
Just start by getting it outside and faceing south :) Simple wooden frame on the ground and use the battery to weight it down ?
 

Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #142 on: February 25, 2018, 09:29:47 am »
I have a solar power system. It is home brew with a 2 by 2 inch solar cell and a nicad power storage capacity of 200 ma at 1.2 volts. This power is automatically used at night to light a single white IR type white LED , 1 volt 20 ma. The reason was to back light an outside temperature gauge so it can be seen at night. All went well for the winter with 3 to 4 hours of a solar powered back lighting. However in the summer the LED attracted small flies. This did not escape the attention of the local spiders who soon set up camp on my solar power system. Not sure what they did but the white LED no longer shines at night. Easier to build another as all the part are in a 4 dollar back yard garden light sold in most stores. I guess my point is even micro solar power systems have their problems. The best laid plans...
That's so funny I have thousands of spiders BUT they refuse to make home in the solar converters, maybe being chopped up by fans, roasted on heatsinks, burnt on 500V terminals and deafened by shreiking 25Khz ferrites doesnt suit them  >:D
 

Offline paulca

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Re: UK solar doldrums
« Reply #143 on: February 25, 2018, 09:43:45 am »
I need to move house and get better panels.

Today I started with 12.0V on the battery and ended with 11.9V.  Took more to run the charge controller and 485 Wifi monitor than I actually got from the sun.  It was a pretty dark and miserably day though.
Just start by getting it outside and faceing south :) Simple wooden frame on the ground and use the battery to weight it down ?

1st (and 2nd) floor apartment.  If I carted it up stairs I could hang it out the skylight onto the roof, but with no way to fix it in place without consulting the landlord it would be "under supervision" on calm days only.   I might do this the next blue sky day to see if I can get the full 50W.

In it's south facing window the most it has produced so far is around 28W.

The charge controller hasn't even clocked to 2kWh and it's been running for over a month now. :)
« Last Edit: February 25, 2018, 09:46:37 am by paulca »
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Offline fourtytwo42Topic starter

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Re: UK solar doldrums
« Reply #144 on: February 25, 2018, 04:33:14 pm »
1st (and 2nd) floor apartment.  If I carted it up stairs I could hang it out the skylight onto the roof, but with no way to fix it in place without consulting the landlord it would be "under supervision" on calm days only.   I might do this the next blue sky day to see if I can get the full 50W.
In it's south facing window the most it has produced so far is around 28W.
The charge controller hasn't even clocked to 2kWh and it's been running for over a month now. :)
Ahh ok, well I hate to suggest polishing the window both sides as maybe you have already done that but I did see someone using baco-foil reflectors with a small panel to improve output!
 

Offline jc101

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Re: UK solar doldrums
« Reply #145 on: February 25, 2018, 06:31:31 pm »
Best day of the year today, managed to get 9.99kWh from our 2.57kW array.

Strategic use of dishwasher, washing machine, and drier has meant that only ~20% was exported today.
 

Offline paulca

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Re: UK solar doldrums
« Reply #146 on: February 25, 2018, 06:38:27 pm »
I had an interesting experience today.  It might be hard to explain... or you will understand straight away and berate me for not knowing....

When the sun is directly in front of the panel  around noon (through a window), leaning it back slightly to "look up at the sun" and get a more direct perpendicular angle, produces a little more current.  This seem intuitive and obvious.  We are talking about producing 23W and leaning to back 10 degrees produces 25W.

However at 2pm when the sun is off to the side a little (not much) the output fall dramatically.  From around 25W to around 6W.

I found this annoying, so I played with the position and found that pointing the panel directly at the sun produced very little output - 5-7W.

Pushing the panel tight against the window and completely off axis with the sun produced the highest output.  20W.

I conclude that the insulation through a window is HIGHLY dependant on the angle of incidence between the panel and the window and less on the angle of the sun and the panel.

EDIT: I think the relationship is the intuitive; "on axis" to the sun is better.  However, loss through the window at an angle is huge, so an off axis panel produces more output than an on axis panel with an angular offset trough glass.  Outdoors the window is removed and an on-axis panel alignment will always win.
« Last Edit: February 25, 2018, 06:46:04 pm by paulca »
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Offline John Heath

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Re: UK solar doldrums
« Reply #147 on: February 25, 2018, 06:49:01 pm »
I have a solar power system. It is home brew with a 2 by 2 inch solar cell and a nicad power storage capacity of 200 ma at 1.2 volts. This power is automatically used at night to light a single white IR type white LED , 1 volt 20 ma. The reason was to back light an outside temperature gauge so it can be seen at night. All went well for the winter with 3 to 4 hours of a solar powered back lighting. However in the summer the LED attracted small flies. This did not escape the attention of the local spiders who soon set up camp on my solar power system. Not sure what they did but the white LED no longer shines at night. Easier to build another as all the part are in a 4 dollar back yard garden light sold in most stores. I guess my point is even micro solar power systems have their problems. The best laid plans...
That's so funny I have thousands of spiders BUT they refuse to make home in the solar converters, maybe being chopped up by fans, roasted on heatsinks, burnt on 500V terminals and deafened by shreiking 25Khz ferrites doesnt suit them  >:D

Electrocution or the nasty indifference of a spinning fan is a little much. We all have to get by in life and I have nothing against spiders.  I just want them away from the micro solar power plant. I am liking the sounds of the shrieking 25 KHz ferrite , pun intended. Bats hunt insects so I imagine most insects would find the ultrasonic chirps of a bat alarming. A low powered PIC programmed to make the ultrasonic sound of a chirping hungry bat every 60 seconds.  This should keep then too nervous to call this home for a good 12 inches around the solar power system. Somewhat like hocks near an airport to keep the birds away. Micro solar power plant 2 should have bat simulated sounds. This would be a chance to home some skills in PIC low power applications. With the addition of smart PIC the micro solar power plant could reach out into other energy sources , a tiny 2 inch fan for those windy days.     
 
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Offline paulca

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Re: UK solar doldrums
« Reply #148 on: February 25, 2018, 06:57:52 pm »
Best day of the year today, managed to get 9.99kWh from our 2.57kW array.

Strategic use of dishwasher, washing machine, and drier has meant that only ~20% was exported today.

While I understand that batteries for that kind of through put are difficult.  Does it not make you think that some sort of storage solution would be beneficial?  I know that I, like many people, are out during the day 5 days a week.  Power requirements for half the year (at these latitudes) are minimal when you are out at work (The whole "solar power day").

For Northern Ireland at 54* North solar without storage would be next to pointless.  Of course the investment companies don't see it that way.  They see the advantage.  They charge you a meer deposit of a few thousand pounds and put 3kw of panels on your roof.  You get to use whatever you want and the rest gets exported to the grid.  But the market is young professionals who are out all day.  They think they are doing their bit for the environment, but really they are doing their bit for the investment banks who fund their panels.

The panels might produce 10kwh that they don't use at a rate of 3p.  But you get none of that on these schemes.  It apparently works out that it's a money maker for the investment banks who have sold decades of energy futures based on it... then dumped the products to the next investor.

On such schemes you are forbidden to install a storage solution as it will directly impact the investors profit...

... or I am exaggerating and the reality is less severe....
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Offline ahbushnell

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Re: UK solar doldrums
« Reply #149 on: February 26, 2018, 02:13:41 am »
I had an interesting experience today.  It might be hard to explain... or you will understand straight away and berate me for not knowing....

When the sun is directly in front of the panel  around noon (through a window), leaning it back slightly to "look up at the sun" and get a more direct perpendicular angle, produces a little more current.  This seem intuitive and obvious.  We are talking about producing 23W and leaning to back 10 degrees produces 25W.

However at 2pm when the sun is off to the side a little (not much) the output fall dramatically.  From around 25W to around 6W.

I found this annoying, so I played with the position and found that pointing the panel directly at the sun produced very little output - 5-7W.

Pushing the panel tight against the window and completely off axis with the sun produced the highest output.  20W.

I conclude that the insulation through a window is HIGHLY dependant on the angle of incidence between the panel and the window and less on the angle of the sun and the panel.

EDIT: I think the relationship is the intuitive; "on axis" to the sun is better.  However, loss through the window at an angle is huge, so an off axis panel produces more output than an on axis panel with an angular offset trough glass.  Outdoors the window is removed and an on-axis panel alignment will always win.

As the sun get's lower in the sky the atmosphere blocks more solar radiation. 
 


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