diy solar

diy solar

Installation under HV lines

Elpida

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Oct 8, 2020
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Hi, my first message so please go easy. I've offered to design and install an off grid 12V lighting system at an animal rescue I support because the local mayor refuses to give us 220V, it's a steep learning curve but I like to think I'm getting there, slowly!

There's one issue that I've come across while searching and I'm not sure how much this may affect things. The shelter is in rural Greece and situated under 7x400kV lines, there's another set of 7 cables about 50M away to the south. At first I thought the only issue might be a little shadowing from the lines across the road but then I discovered a report about the magnetic field from HV lines reducing the efficiency of PV panels. Apart from this one report I can't find any practical experiences of it happening or any hard and fast figures.

I wonder if this is something somewhere here has come across and if so how bad the problem actually is. I'd like to think I could just increase the amount of panels and storage to compensate if this is a real issue as each system will only have 8x10W LED floods on it.

Paul
 

50m results in a magnetic intensity of 0.5uT.


Indicates that a 0.5mT intensity impacts PV production by about 2% (Rable 3)

0.5mT is 500uT, so the magnetic field 50m from 400kV lines is 1000 times weaker than a magnetic field that produced a 2% power drop.

I have no authority or expertise in this area. I'm just a monkey exercising its Google-Fu and converting units/doing arithmetic.
 
Thanks Snoobler! That's a lot more maths than I can cope with but given those figures I don't think there's too much to worry about especially with the limited amount of power required each day.
 
I tried to summarize. I'll phrase it this way:

The EM interference from HV power lines 50m away would need to be 1000 times stronger to cause a 2% PV power loss. Not a concern.

:)
 
Hi, my first message so please go easy. I've offered to design and install an off grid 12V lighting system at an animal rescue I support because the local mayor refuses to give us 220V, it's a steep learning curve but I like to think I'm getting there, slowly!

There's one issue that I've come across while searching and I'm not sure how much this may affect things. The shelter is in rural Greece and situated under 7x400kV lines, there's another set of 7 cables about 50M away to the south. At first I thought the only issue might be a little shadowing from the lines across the road but then I discovered a report about the magnetic field from HV lines reducing the efficiency of PV panels. Apart from this one report I can't find any practical experiences of it happening or any hard and fast figures.

I wonder if this is something somewhere here has come across and if so how bad the problem actually is. I'd like to think I could just increase the amount of panels and storage to compensate if this is a real issue as each system will only have 8x10W LED floods on it.

Paul

Hope the project goes well. Sorry, I can't offer any advice on this one, but great you are supporting the animal rescue centre. ?

Off topic, but we have had some dealings with a dog shelter in Evia, and rescued a puppy abandoned on a beach near the Glyfa ferry four years ago who is now happily living with us in the UK. Animals have a tough time in Greece so you're a hero in my book :)
 
Thanks ClarkP, you're right about the tough time they have and unfortunately it seems to be part of the local mentality to treat most strays as a nuisance to get rid of, usually involving poison or a length of rope. Well done you on adopting a dog out there and Glyfa is not far north from our place in Livadia :)

The lady who runs our rescue in Livadia has a full time job as well as a daughter so does all the cleaning at night using nothing more than a Petzl head lamp!! 70 dogs in 40 pens takes her about six hours so as you can imagine I'm trying to make her life a little less tough by giving her some decent light.

I've not bought any of the expensive parts yet , I now know the size system I need but I'm still looking for an IP55 or better rated MPPT controller in my price range.

I have purchased a selection of 12V led lights, both E27 bulbs and mini floodlights to see which offers the best and most cost effective way of lighting each pen. Once they've arrived I'll rig up a test system using a power supply so I can gauge lighting levels then buy the PV stuff so I can thoroughly test everything here before sending it out to Greece. As you can imagine, everything needs to be super reliable, weather proof in the extreme, dog proof and rat proof, it's been quite a learning curve :LOL:
 
Thanks ClarkP, you're right about the tough time they have and unfortunately it seems to be part of the local mentality to treat most strays as a nuisance to get rid of, usually involving poison or a length of rope. Well done you on adopting a dog out there and Glyfa is not far north from our place in Livadia :)

The lady who runs our rescue in Livadia has a full time job as well as a daughter so does all the cleaning at night using nothing more than a Petzl head lamp!! 70 dogs in 40 pens takes her about six hours so as you can imagine I'm trying to make her life a little less tough by giving her some decent light.

I've not bought any of the expensive parts yet , I now know the size system I need but I'm still looking for an IP55 or better rated MPPT controller in my price range.

I have purchased a selection of 12V led lights, both E27 bulbs and mini floodlights to see which offers the best and most cost effective way of lighting each pen. Once they've arrived I'll rig up a test system using a power supply so I can gauge lighting levels then buy the PV stuff so I can thoroughly test everything here before sending it out to Greece. As you can imagine, everything needs to be super reliable, weather proof in the extreme, dog proof and rat proof, it's been quite a learning curve :LOL:

You could mount a decent standard MPPT controller into an IP55 box like this? https://www.ebay.co.uk/itm/173356493281

I think most weatherproof controllers are PWM, which isn't necessarily a problem for this application. Morningstar SG4 I think is a possible?

But, are you over complicating things? Could you just use a few self contained solar flood lights like these? https://www.ebay.co.uk/itm/124001240932 although there are better quality ones around than this.

We have similar around the perimeter and garden of our off grid cabin in the UK and they work well all year round.

Just a thought ?

Good luck with whichever solution you go for ?
 
You could mount a decent standard MPPT controller into an IP55 box like this? https://www.ebay.co.uk/itm/173356493281

I think most weatherproof controllers are PWM, which isn't necessarily a problem for this application. Morningstar SG4 I think is a possible?

But, are you over complicating things? Could you just use a few self contained solar flood lights like these? https://www.ebay.co.uk/itm/124001240932 although there are better quality ones around than this.

We have similar around the perimeter and garden of our off grid cabin in the UK and they work well all year round.

Just a thought ?

Good luck with whichever solution you go for ?
Those solar floods look useful but I think the dogs bouncing around will probably mean they'll be on permanently, or least make the shelter look like a disco :LOL: I'll order one and see if they can modified to be hard switched.

I'm concerned about putting the controller in a water tight box because it's not uncommon for the air temperature to reach 40C in the summer and I think they'll need ventilation and some heak sinking. The pens are actually made of sheet steel so I'm leaning towards bolting the controllers directly to a north facing wall and mounting a cover over them, just haven't decided what or how yet.
 
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