diy solar

diy solar

Hello from the Sussex, UK

Kman68

New Member
Joined
Sep 25, 2020
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48
Hello all,

Long term lurker here, but decided to introduce myself to you all.

My goal to is add a solar / home power system to my house, here on the south coast of England, and I will require some advice.

So, let me explain where I am on my home power journey.

Firstly I definitely want to reduce my reliance on (peak) Grid electricity and natural gas, so I want to get as much solar PV energy into the mix as possible. The challenge is that our house is the northern facing one of a semi-detached pair. However, we've recently moved to Octopus Energy, who provide a 100% renewable tariff, and having had a smart meter installed this week, we will hopefully be moving to their Agile Tariff soon, which allows customers to leverage drops in energy pricing.

To use this properly, I really need to build a home battery system, to charge at the cheapest rates and use at peak times, so that's my first goal. I'm in the process of assessing the overall 'demand' of the house to size this.

Adding solar PV is tricky as I mentioned, but we had a loft conversion previously, so I'm thinking I might be able to put some up top on that. See photo below:

Screenshot_20201014_225555_2.jpg

Is this possible, I have concerns about having panels exposed like that, so your advice on ALL of this will help.

I'd also love to explore heat pumps for heating the house, to remove the costly and polluting natural gas from the system, but this is VERY expensive here.

So, hello everyone, I'm open to suggestions...
 
Welcome to the forum.

The only truly viable option I see is the flat roof, and that may be fairly limiting.

IMHO, research with your local authority concerning the requirements for panel mounting. That's going establish your hard limits.

Second, what is your available solar? Link #5 in my signature.

Third, while you said you're on it, many utilities have usage data readily available. That's typically the best place to start, and you can have numbers useful for planning in mere minutes. If you can get it down to monthly kWh numbers, that helps a lot. You need to design your system such that you're meeting your worst case situation.

You should also look at your natural gas usage. While I can't do it off the top of my head, one can estimate kWh needed to replace BTU used for heating.
 
Thanks @snoobler for the welcome.

I will enquire as to the local requirements, good call.

Re available solar.... with completely horizontal panels, for Brighton, about 10 miles away I get:

JanFebMarAprMayJun
0.88
1.62
2.67
4.19
5.38
5.66
JulAugSepOctNovDec
5.58
4.76
3.24
1.90
1.08
0.67
 
That site also incorporates average weather influence on solar availability.

December and January are atrocious. If you could use your flat roof in the same manner one would use the ground to mount a fully tilted array, that might be workable, but I suspect there are height restrictions that might prevent that. It would also be butt-ugly.

Even with your panels at the optimal winter tilt of 66° from horizontal:

JanFebMarAprMayJun
1.542.453.144.044.344.29
JulAugSepOctNovDec
4.294.303.632.701.851.22

Your Dec and Jan production are terrible.

Your solar availability suggests that it may be very difficult or impossible for you to go completely off-grid, but this really depends on your kWh/day usage.

Your plan to completely replace heating with heat pumps should DEFINITELY be a secondary goal. This may likely never be viable.

Continued slogging through the maths will get the answers.
 
It is highly unlikely that we would ever be able to go fully off grid, yes. where I'd like to get to is a place where we can use a mix of free solar (particularly spring to Autumn) plus cheaper off peak electricity via a battery to remove any reliance on peak price electricity. Later I want to add an EV to the mix, so overnight charging / solar charging becomes part of the overall mix.
 
Hi Kman.
Are you on LPG or mains gas?
If LPG then worth looking at EDF heat pump offer.
 
Hello all,

Long term lurker here, but decided to introduce myself to you all.

My goal to is add a solar / home power system to my house, here on the south coast of England, and I will require some advice.

So, let me explain where I am on my home power journey.

Firstly I definitely want to reduce my reliance on (peak) Grid electricity and natural gas, so I want to get as much solar PV energy into the mix as possible. The challenge is that our house is the northern facing one of a semi-detached pair. However, we've recently moved to Octopus Energy, who provide a 100% renewable tariff, and having had a smart meter installed this week, we will hopefully be moving to their Agile Tariff soon, which allows customers to leverage drops in energy pricing.

To use this properly, I really need to build a home battery system, to charge at the cheapest rates and use at peak times, so that's my first goal. I'm in the process of assessing the overall 'demand' of the house to size this.

Adding solar PV is tricky as I mentioned, but we had a loft conversion previously, so I'm thinking I might be able to put some up top on that. See photo below:

View attachment 37360

Is this possible, I have concerns about having panels exposed like that, so your advice on ALL of this will help.

I'd also love to explore heat pumps for heating the house, to remove the costly and polluting natural gas from the system, but this is VERY expensive here.

So, hello everyone, I'm open to suggestions...
I've missed why you can't put them on the south facing roof?
 
I’ve never seen a duplex house owned by two different people like that. Are you renting, or is this a condo/townhouse situation?
 
If it were me, i would probably use a mix of solar collectors rather than all PV. The garage could have a frame added on its northern side and the whole length covered in an evacuated tube array(shouldn't be a massive weight), which could provide your year round domestic hot water. An air source heat pump located inside a small greenhouse with a black painted concrete base, (would help raise the air temp intake a fraction and cut down noise), located on the south facing wall behind the garage, could provide the house heating requirements, thus eliminating your nat gas usage. The panels on your flat roof might be able to be tilted towards south a little, doubtful by much, but every little bit helps. I'm presuming your prevailing winds are from the south, but the loadings on your flat roof would need calculating very accurately. Being a semi detached, i would probably opt for a professional instal of the flat roof-panels, with the engineering/warranty backing...but that's just me. In Scotland over a decade ago, a PV roof system was permitted developement, but the installer still needed a building warrant.....not sure what the latest rules are?

example 1.jpg
 
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If it were me, i would probably use a mix of solar collectors rather than all PV. The garage could have a frame added on its northern side and the whole length covered in an evacuated tube array(shouldn't be a massive weight), which could provide your year round domestic hot water. An air source heat pump located inside a small greenhouse with a black painted concrete base, (would help raise the air temp intake a fraction and cut down noise), located on the south facing wall behind the garage, could provide the house heating requirements, thus eliminating your nat gas usage. The panels on your flat roof might be able to be tilted towards south a little, doubtful by much, but every little bit helps. I'm presuming your prevailing winds are from the south, but the loadings on your flat roof would need calculating very accurately. Being a semi detached, i would probably opt for a professional instal of the flat roof panels, with the engineering/warranty backing...but that's just me. In Scotland over a decade ago, a PV roof system was permitted developement, but the installer still needed a building warrant.....not sure what the latest rules are?

View attachment 37499
Thanks Jim. that's a very good idea. I was thinking about getting the garage renovated anyway, and maybe adding a pitched roof, which although reducing the available area facing south, would give any tube array a better angle. We do have an unused space behind the garage (there's a greenhouse further West).

I would certainly go with a pro installer for any solar PV 'up top' as it needs to be secure & safe. As I mentioned before, I don't aspire to complete independence from the grid, but I want to rely on cheap electricity and solar to power the house and a future EV.

The water heating idea is brilliant, plus the air sourced pump is far enough away from the house and discrete where you've suggested.
 
Remembering my visits to Brighton and Hove, it was always blowing a gale. How about a wind turbine?
 
Remembering my visits to Brighton and Hove, it was always blowing a gale. How about a wind turbine?

As you know, the gentleman who started this thread lives on the English Channel. I've spent a lot of time on the Isle of Wight, just off Southampton to his west. @snoobler's observations on the solar conditions (post #4) gave me a chuckle. If one has a farm, wind is the obvious choice, but I doubt that it's practical in a residential area. I'm curious to know whether he went ahead with this.
 
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My Brother in law has recently purchased a cheap wind turbine to add to his homemade solar / battery setup, but it's producing poor results. Does anyone have a recommendation of a wind turbine that is worth the money?

I have an update on the solar stuff, I'll get the details and report back.
 
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