Best location to put PV inverter and batteries

podge3 · 01-02-2023 1:44pm #1

I'll be (finally!) getting my solar PV installed in a few months time and I'm trying to decide the best location for the inverter and batteries.

Most people put theirs in the attic but this means the inverter may suffer with heat during the hottest summer days and the batteries would be affected in the cold of winter.

I could put mine at the back of an unheated clothes press but I'm a little concerned about the fire risk with the clothes if anything were to go wrong with the electrical stuff. Both temperature issues in the attic wouldn't be a concern here. Obviously there is also a fire risk in the attic but probably much less. A fire alarm would be a must in both locations IMHO.

Any thoughts?

Big Lar · 02-02-2023 8:19am

Have mine in the utility, there is a nice bit of heat generated/lost with conversion from DC to AC and vice versa with batteries so for me having the inverter in garage or attic is a waste of that energy. Its more accessible also in a room if you need to change charging rates/times etc - course some people can do that remotely from phone/web.

If you put it in the clothes drying room I would imagine that you will have a lot of condensate so I am thinking that may be an issue along with the possibility of people throwing clothes on top of the inverter preventing air flow.

slave1 · 02-02-2023 9:24am

Inverters in attic, don't care if they slow down due to summer heat as I'll be in excess generation anyhow, battery inverter/batteries in utility room to avoid the temp ranges experienced in the attic

DC999 · 02-02-2023 9:48am

My inverters are outside right behind fuseboard. 8 foot high so won't get hit or messed with. Outdoor rated. So you have options.

micks_address · 02-02-2023 12:26pm

We were lucky with our house that it had an old oil boiler room built into the side of it. The oil has long gone but the space was still there and perfect for battery/invertor. I bought a temp sensor and have been keeping an eye on it and it's grand. Even had an old flu running right to the roof which the installer was able to run the panels cables down.

Alun · 02-02-2023 12:33pm

Apart from temperature considerations are there any other restrictions on putting both inverter and any batteries in the attic?

We're in a semi-detached bungalow and the only solid wall in the attic is the block party wall, I assume that isn't an issue? It is quite a shallow roof though, so the only real option on this wall would be the chimney breast, and given the shallowness of the roof there's not a massive amount of room. Are there any restrictions on how far the inverter and batteries have to be from any potentially flammable items such as roof joists or attic flooring?

I've no utility room or anything similar, only a small storage cupboard in one corner that's an odd triangular shape and way too small.

Is there any way both items could be installed outdoors against an exterior wall perhaps?

Bass Reeves · 02-02-2023 12:34pm

Sealed batteries do not like constant temperature change and extremes above 18-20c are far from an ideal senario. It will drastically reduce there lifespan. Ideally they should be in a temp controlled zone however failing that so e place it is not varying constantly.

podge3 · 02-02-2023 12:38pm

https://www.boards.ie/discussion/comment/120190561#Comment_120190561

Its not a really a drying room, more of an unheated hotpress, condensation wouldn't be an issue. Also, the clothes wouldn't be on the inverter, the room is quite deep. My main concern would be the flammable nature of the clothes in the event of an issue with the electrical units.

podge3 · 02-02-2023 12:40pm

https://www.boards.ie/discussion/comment/120190886#Comment_120190886

Putting the inverter outside isn't really an option for me, although that would be my no. 1 choice if I could.

podge3 · 02-02-2023 12:41pm

https://www.boards.ie/discussion/comment/120191557#Comment_120191557

An ideal setup, getting the inverter and battery outside, while still protected from the weather and easily accessible.

podge3 · 02-02-2023 12:45pm

https://www.boards.ie/discussion/comment/120191582#Comment_120191582

Most installations I've seen pics of have the inverter mounted on plasterboard or some kind of fireproofed backing. That being said, a well-known installer put up several pics the other day of his recent installations and the inverter was mounted straight to the wall. I thought it was a regulation but maybe not.

Most/all inverters are weatherproof, some people do put them outside. Not sure on the batteries.

micks_address · 02-02-2023 1:21pm

ive seen some on the givenergy forums who have mounted their equipment outside say they have had reduced charging of batteries on cold nights in december/january. Probably not that a big of a deal as its only a few nights will be really cold. the temp sensor on top of my battery has min of 7.8 degrees on coldest night in jan.. to about 18.5 max.. which is probably fine.. i actually added vents to the door to allow more air circulation in case of overheating.. im sure it will get a bit warmer in the summer but shouldn't be anything major.. ive noticed the hottest temp seems to be around the invertor when charging/discharging the battery

Temp graph.. you can see where I added extra ventilation

unkel · 02-02-2023 1:34pm

Inverters are all waterproof and can be installed outdoors, but be sensible and don't install them where they get direct mid day sunlight or in the path of driving rain from prevailing winds

As for batteries, it depends. For one on the chemistry. Tesla power walls can only be installed outdoors or in garages or other outbuildings that aren't inhabited, as they use lithium ion chemistry (for now), which is too dangerous to keep inside your home. That's why your mobile phone, your cordless toothbrush, powertools, eBike batteries and torches should all be kept outside your house really, or at least being charged overnight outside of your house 😂

Lithium Iron Phosphate (LiFePO4) batteries are safe to mount indoors. They usually can also be mounted outdoors, as long as their BMS has temp control (most pre made packs do) as charging them below 0C will damage the cells, so must be prevented

Bass Reeves · 02-02-2023 2:05pm

https://www.boards.ie/discussion/comment/120191853#Comment_120191853

A small room even vented with an inverter in and batteries could teach the high twenties Centigrade in tem with boundaries summer time if in direct sunlight. I think I've looking at a fan system and maybe a mini cooler for the summer. Wintertime the inverter will probably give adequate heat( unless a long cold spell) to keep temp above 5-6C. In the case of a cold spell some firm of glass fiber or Rockwood would be adequate to keep temp above min required

micks_address · 02-02-2023 2:14pm

https://www.boards.ie/discussion/comment/120192133#Comment_120192133

yeah thats why i put the temp sensor in there.. ill keep an eye on it.. the high temps at the start of the graph where where i had the sensor at the entry to the flu which probably was venting all the temp.. its definitely cooler now.. its on side of house where no sunlight ever shines.. joys of being in an estate..

con747 · 02-02-2023 2:28pm

https://www.boards.ie/discussion/comment/120191627#Comment_120191627

I know at least 1 person on boards bought something similar to this https://www.argos.ie/static/Product/partNumber/8667971/c_1/1%7Ccategory_root%7CGarden+and+DIY%7C14418702/c_2/3%7Ccat_19285823%7CSheds%2C+greenhouses+and+storage%7C14418827/Trail/searchtext>CLEARANCE.htm and put it outside mounted to the house wall for everything. You could insulate for winter and open it for excess heat in summer.

micks_address · 02-02-2023 2:47pm

on the speedmaster.. should be able to pick up the newer reference for 4.5 to 5k on preowned market.. was looking at some in the US last week.. always looking at speedmasters :)

unkel · 02-02-2023 2:48pm

https://www.boards.ie/discussion/comment/120192407#Comment_120192407

Is a speedmaster one of those solar PV panels that has been to the moon? A moon panel?

(I'd say of the regulars in this forum, only @banie01 and @micks_address will get this 😂)

micks_address · 02-02-2023 3:13pm

https://www.boards.ie/discussion/comment/120192415#Comment_120192415

how did that happen :) boards cross posting.. maybe my head is still in the US :)

Bass Reeves · 02-02-2023 3:13pm

https://www.boards.ie/discussion/comment/120192194#Comment_120192194

Another reason is because these batteries will be there for a substantial time and the tendency will be not to replace them every now and again I e of these will burst. They are unlikely to leak acid and the tray should collect that anyway, but the smell can be horrendous and will take awhile to get rid of