I’ve been struck by the solar lightning bug! (Setup advice)

[Jourdain]

It's like the universe went, "Hey you, time to ditch everything and focus your life on solar". I've even outdone my own personal record of YouTube binge-watching and forum deep dives. But enough about my spiral into solar madness, can you help me!! (pics attached for reference).

Me:
- Pretty handy but no electrical experience
- live in the UK (South East London)
- My roof isn't big enough for the 20kw array I dream about, it's not even big enough for 4/5 panels, it's not even south-facing (crying side).
- My garden on the other hand is 35m long and has plenty of space for ground array. I have a summer house that could fit pannels (maybe 6) a workshop that could fit pannels (maybe 6) and soon to be garden office (maybe 4)
- My house and garden face South East (135 degrees)
- ISSUE - I'll have to cut 1 fairly big tree down but that would open up my whole garden basically and allow panels to be south-facing. As much as I said I would never do that, I can justify it to have solar.

The goal:
- Learn solar!
- Reducing bills a little in the process is a bonus... while the payback period and all that jazz are interesting to me, it's not the main focus here.
- Potentially power a small garden office that will be 2x2m and have as much insulation as I can physically fit. (Laptop charger, phone charger, screen, and potentially heating)
- The system would likely be in an outside shed/workshop and need to handle UK temps

My current direction
- Off-grid - This will allow me to learn and not have to pay electricians etc
- Spend money on an inverter and batteries mainly (£1000) and have a few solar panels to start, then add more panels as I go.
- Charging the battery during off-peak times from the grid would be a bonus. (so only draw from the grid, not send any back)
- I would like to increase the number of panels over time (maybe between 5 - 10kw would be the end goal and feed the house)
- I would like to increase the battery storage over time

Potential system (needs to be accessible in the UK)
- All-in-one Growatt Inverter (or similar) that can handle a decent PV input, charge from mains and PV at a decent rate etc.
- 100ah LiFePO4 battery (Although it seems temp can be an issue)
- 24v system (I have seen a lot of 24 vs 48 discussions)
- Isolators etc, I'm learning... but safety is at the front of my brain.
- 400w panels (potentially with optimizes as the panels would likely have shading issues until I chop the tree)

To be honest, I just like the thought of tinkering and harnessing energy from the sun. Starting like this will allow me to grow and learn which is the main thing.

Questions...
1. Do you think this is a good approach?
2. 24v seems like a good middle ground, would you go 24 or 48? (I know the larger investors and bigger batteries are 48v). Also cheaper for longer cable runs which could be an issue in my long narrow garden.
3. Is there something obvious I've missed that throws a spanner in the works?
4. I have £1500 to spend, can you recommend UK products?

Thanks for reading what is essentially 2 weeks of obsession. Any input is helpful, just to satisfy my needs!

Cheers,
Jourdain

 

[Mirlen]

Looks like you have a pergola over your back patio? Could be an option to put some panels up on there, bifacials if you want to let some light thru which will keep it feeling brighter/more open (And gain slightly more watts) and it's closer to the house... ?

 

[Jourdain]

Looks like you have a pergola over your back patio? Could be an option to put some panels up on there, bifacials if you want to let some light thru which will keep it feeling brighter/more open (And gain slightly more watts) and it's closer to the house... ?

Yeah, I have thought about this as well, but it's been bookmarked for climbing plants before my solar addiction so right now it's out of the question. Although it probably would have been perfect!

Good to hear I'm not the only one! How are you coming along with your system?

 

[Mirlen]

Yeah, I have thought about this as well, but it's been bookmarked for climbing plants before my solar addiction so right now it's out of the question. Although it probably would have been perfect!

Good to hear I'm not the only one! How are you coming along with your system?

HAH! My "system" right now consists of 2 100W panels I drag around the yard trying to catch photons connected to a Victron 100/30 and a little 50Ah battery... all smiles while in bulk charging mode, then I panic in absorption as I run around the house trying to find things to charge, grab to Toro 60V Max battery powered yard tools and do a frantic edging and blowing, then swing back to the charge controller, turn on the dirty def-not-a-sinewave 300W inverter and plug in the Toro batteries to charge...giving a sigh of relieve as my watts have a place to live. Did a quote on a whole house system and came up at about $129,000 for 92 REC panels and SolarEdge equipment, wife not up for that So I'm trying to feed my addiction as best I can w/o draining the wallet too much and not getting arrested/fined.... I am looking at picking up a couple 200W panels for now and hanging them on a fence that is around our AC units as our house faces almost EXACTLY true-south for the rear yard....

 

[Jourdain]

HAH! My "system" right now consists of 2 100W panels I drag around the yard trying to catch photons connected to a Victron 100/30 and a little 50Ah battery... all smiles while in bulk charging mode, then I panic in absorption as I run around the house trying to find things to charge, grab to Toro 60V Max battery powered yard tools and do a frantic edging and blowing, then swing back to the charge controller, turn on the dirty def-not-a-sinewave 300W inverter and plug in the Toro batteries to charge...giving a sigh of relieve as my watts have a place to live. Did a quote on a whole house system and came up at about $129,000 for 92 REC panels and SolarEdge equipment, wife not up for that So I'm trying to feed my addiction as best I can w/o draining the wallet too much and not getting arrested/fined.... I am looking at picking up a couple 200W panels for now and hanging them on a fence that is around our AC units as our house faces almost EXACTLY true-south for the rear yard....

That made me laugh! I've also looked at full house installs and while I like the idea, it doesn't satisfy my need to know more (but it has crossed my mind). I figured starting small in the garden would put me on the right path, once I see the benefits.. I can expand and take over every south-facing spot possible. haha

 

[Tomthumb62]

I would recommend starting with a small 12v system with the cheapest components you can buy. Learn on that.

 

[bt77]

It's like the universe went, "Hey you, time to ditch everything and focus your life on solar". I've even outdone my own personal record of YouTube binge-watching and forum deep dives. But enough about my spiral into solar madness, can you help me!! (pics attached for reference).

Me:
- Pretty handy but no electrical experience
- live in the UK (South East London)
- My roof isn't big enough for the 20kw array I dream about, it's not even big enough for 4/5 panels, it's not even south-facing (crying side).
- My garden on the other hand is 35m long and has plenty of space for ground array. I have a summer house that could fit pannels (maybe 6) a workshop that could fit pannels (maybe 6) and soon to be garden office (maybe 4)
- My house and garden face South East (135 degrees)
- ISSUE - I'll have to cut 1 fairly big tree down but that would open up my whole garden basically and allow panels to be south-facing. As much as I said I would never do that, I can justify it to have solar.

The goal:
- Learn solar!
- Reducing bills a little in the process is a bonus... while the payback period and all that jazz are interesting to me, it's not the main focus here.
- Potentially power a small garden office that will be 2x2m and have as much insulation as I can physically fit. (Laptop charger, phone charger, screen, and potentially heating)
- The system would likely be in an outside shed/workshop and need to handle UK temps

My current direction
- Off-grid - This will allow me to learn and not have to pay electricians etc
- Spend money on an inverter and batteries mainly (£1000) and have a few solar panels to start, then add more panels as I go.
- Charging the battery during off-peak times from the grid would be a bonus. (so only draw from the grid, not send any back)
- I would like to increase the number of panels over time (maybe between 5 - 10kw would be the end goal and feed the house)
- I would like to increase the battery storage over time

Potential system (needs to be accessible in the UK)
- All-in-one Growatt Inverter (or similar) that can handle a decent PV input, charge from mains and PV at a decent rate etc.
- 100ah LiFePO4 battery (Although it seems temp can be an issue)
- 24v system (I have seen a lot of 24 vs 48 discussions)
- Isolators etc, I'm learning... but safety is at the front of my brain.
- 400w panels (potentially with optimizes as the panels would likely have shading issues until I chop the tree)

To be honest, I just like the thought of tinkering and harnessing energy from the sun. Starting like this will allow me to grow and learn which is the main thing.

Questions...
1. Do you think this is a good approach?
2. 24v seems like a good middle ground, would you go 24 or 48? (I know the larger investors and bigger batteries are 48v). Also cheaper for longer cable runs which could be an issue in my long narrow garden.
3. Is there something obvious I've missed that throws a spanner in the works?
4. I have £1500 to spend, can you recommend UK products?

Thanks for reading what is essentially 2 weeks of obsession. Any input is helpful, just to satisfy my needs!

Cheers,
Jourdain

I like the approach in general but I wouldn't go for 24 V. Decreased efficiency due to lower voltage, and yes long cable run does not fit well with low voltage. What worries you about 48 V? Cost, safety?
I mean I have neither as I have a Huawei high voltage system as the LUNA2000 batteries are 385 V but if I had a low voltage system, I would at least go with 48 V.
Oh by the way, please don't cut the tree. It's more important than a solar installation.

 

[Jourdain]

I like the approach in general but I wouldn't go for 24 V. Decreased efficiency due to lower voltage, and yes long cable run does not fit well with low voltage. What worries you about 48 V? Cost, safety?
I mean I have neither as I have a Huawei high voltage system as the LUNA2000 batteries are 385 V but if I had a low voltage system, I would at least go with 48 V.
Oh by the way, please don't cut the tree. It's more important than a solar installation.

Tree - I know, I'm still thinking about it myself. I could only justify it if I have lots of panels if that makes sense. If I offset my carbon substantially through the panels then it somehow balances in my mind (in theory). It would be the difference between full sun all day and probably half a day's sun on the panels.

48v - Safety mainly. My initial research led me to 24v but I'd be open to 48v if it makes sense. 12v seems out of the question due to the length of cable runs. If I keep the tree the panels will be around 5 / 10 m from the invertor to get the best sun.

How's the Huawei high voltage system?

 

[SeaGal]

Welcome to the mad-house But only "2 weeks of obsession" ?

Here's my 2p worth...

- My roof isn't big enough for the 20kw array I dream about, it's not even big enough for 4/5 panels, it's not even south-facing (crying side).

How much could you get on the south-east and south-west facing roof? I assume the extension is just ground floor with skylight, so that's a no-go?

- My garden on the other hand is 35m long and has plenty of space for ground array. I have a summer house that could fit pannels (maybe 6) a workshop that could fit pannels (maybe 6) and soon to be garden office (maybe 4)

Is there also more space at the bottom of your garden, beyond the tree marked for death-row?

- Potentially power a small garden office that will be 2x2m and have as much insulation as I can physically fit. (Laptop charger, phone charger, screen, and potentially heating)

Good goals, but heating the outbuilding will need lot of power and batteries, assuming you will need to heat when the sun isn't shining.

- The system would likely be in an outside shed/workshop and need to handle UK temps

Battery will need a heater, but can DIY that cheaply.

My current direction
- Off-grid - This will allow me to learn and not have to pay electricians etc
- Spend money on an inverter and batteries mainly (£1000) and have a few solar panels to start, then add more panels as I go.

You will need to consider minimum number of panels to give enough voltage for the inverter to operate.

- Charging the battery during off-peak times from the grid would be a bonus. (so only draw from the grid, not send any back)

Should be an essential, not just a bonus.

- I would like to increase the number of panels over time (maybe between 5 - 10kw would be the end goal and feed the house)
- I would like to increase the battery storage over time

Yep. We all want more panels and batteries
If you are considering increasing to 5 to 10kW and if you can afford it, I'd consider going grid-tied, rather than an off-grid solution. Then it is easier to incrementally power the house, without having re-wiring and 'running-out-of-power-issues'.

Do a thorough audit on what your daily & monthly consumption is and what is your peak usage. That is essential for deciding what size system you will need.

Potential system (needs to be accessible in the UK)
- All-in-one Growatt Inverter (or similar) that can handle a decent PV input, charge from mains and PV at a decent rate etc.

I have a Solis, as do many others in the UK, deye/sunsync are also popular over here.

- 24v system (I have seen a lot of 24 vs 48 discussions)

48V would be far better and more standard. More choice of inverters and and the current you will be drawing on your DC cables will be half that of a 24V system. For sure, 24V would be OK for the office without heating, but if you are looking to get to 5-10kW, I'd only consider 48V myself.

To be honest, I just like the thought of tinkering and harnessing energy from the sun. Starting like this will allow me to grow and learn which is the main thing.

It's addictive!

Questions...
1. Do you think this is a good approach?

See my comments above.

2. 24v seems like a good middle ground, would you go 24 or 48? (I know the larger investors and bigger batteries are 48v). Also cheaper for longer cable runs which could be an issue in my long narrow garden.

I'd go 48V for the reasons given above. Not an issue so much with cable runs as you won't be running 24V/48V DC long distances (only a meter or two distance between battery and inverter). The long distances will either be low current PV (=high voltage) or AC mains and will not be dependent on the battery voltage.

3. Is there something obvious I've missed that throws a spanner in the works?
4. I have £1500 to spend, can you recommend UK products?

Regarding question 3).... my answer is only your budget in point 4).

I think that budget is too small to start with a system you can grow to 5-10kW. It would be OK, IMHO, for something to start with, but you'll probably need to replace it, rather than grow it. But, that's my opinion on what I've read and when you've done the power audit then YMMV.

 

[fpgt72]

You sound a bit like me. I don't know your laws there so I will assume it is ok for you to start screwing with electrical in your house. Personally I think it is a must if you want to learn about this stuff. And that is what I wanted as well, but for me you need to think along the lines of crazy end of the world mad max type stuff as well.

My system is all done by me, and like you the bug bit me HARD last year, here in the US you can take tax credits for this stuff and it is quite nice to offset the costs.

You will need some electrical ability to do this all yourself. It can be a bit scary, and depending on your experience can be pretty big curve or not too much. Have you replaced an outlet in your house before, if no that is one thing. If you have run a new circuit you have no worries.

My system (I need to do a thread) is a on or off kind of deal and lives in my shop. A 28x30 building with 24' side walls. 'merican here everything is in old money here. When I want solar power I will flip a switch on a manual transfer switch. I can choose what circuits I can power. I can run "almost" everything in the shop but the car lift and AC. I only have a 110 inverter. My inverter and batteries are on a cart that I can roll into the house and power whatever I want there. Solar panels mounted to the shop.

Idea is to power the house at night with the batteries, recharge in the day with small use of the generator to keep freezers and such running.

Getting very close to a entire house test, just need for it to cool off a bit more. I can't run the AC in the house.

I will say it is great fun, and you will learn a great deal. But you don't want to run a fowl of any laws, and that electric stuff can kill you bad and it will hurt the entire time it is killing you. So know what you are doing. Don't know if they have classes there for electrician 101 but it might be an idea.

 

[Jourdain]

How much could you get on the south-east and south-west facing roof? I assume the extension is just ground floor with skylight, so that's a no-go?

Really not that much, unfortunately. I've added a pic for reference (roof.jpg) so you can see the roof (ignore the ridge tiles, they are on the fix list). The flat roof of the kitchen extension does indeed have a skylight so not enough space. We will likely be extending the house in the next 5/10 years so that's a big consideration and why I'm leaning towards the garden.

Is there also more space at the bottom of your garden, beyond the tree marked for death-row?

Yes, another picture is attached showing the end of the garden (garden-rear.jpg). This gets light for most of the day but the tree does come into play later in the day. The garden office is planned for the end of the garden (30m from the house). I could do a canopy as well at the side of the office to give more roof space. That would be about 5m wide max and 2.5m high (ish).

Good goals, but heating the outbuilding will need lot of power and batteries, assuming you will need to heat when the sun isn't shining.

Yeah, I've read a lot about heating. I would be building the garden office from scratch so the insulation will be pretty extensive. I think it's better to look at offsetting the cost rather than running completely. A small mini-split or infrared radiator at 600w roughly, plus the other charging devices and LEDs.

Battery will need a heater, but can DIY that cheaply.

Nice! Anything I can research?

I have a Solis, as do many others in the UK, deye/sunsync are also popular over here.

I've seen lot's of Solis, they look good form the reviews. I'm assuming you have had a good experience?

You will need to consider minimum number of panels to give enough voltage for the inverter to operate.

Understood!

48V would be far better and more standard. More choice of inverters and and the current you will be drawing on your DC cables will be half that of a 24V system. For sure, 24V would be OK for the office without heating, but if you are looking to get to 5-10kW, I'd only consider 48V myself

Understood! Good point about the cable runs as well ??

It's addictive!

I normally get addicted and love research but this is another level!

If you are considering increasing to 5 to 10kW and if you can afford it, I'd consider going grid-tied, rather than an off-grid solution.

My main question on this is... can I adjust and play with the system? IE... I want to add another 4 panels. Can I do that or does every change need approval? Obviously, I understand why, it's not an annoyance just a consideration. Truth be told I could go grid tied but I've learnt over the years that my obsessions = cost. So I try to limit that so I'm not banished to the shed ?

Do a thorough audit on what your daily & monthly consumption is and what is your peak usage

How does one do this?

Cheers for your detailed reply!!

 

[SeaGal]

I don't know your laws there so I will assume it is ok for you to start screwing with electrical in your house.

Have you replaced an outlet in your house before, if no that is one thing. If you have run a new circuit you have no worries

In the UK electrical work will need to be done to IET BS 7671 standards by a competent person.

You will also need to meet building regulations part P compliance, which means some work, such as installing a new circuit will require a sparky to install or a friendly sparky to sign DIY work off.

Minor work, such as replacing an outlet (we call them sockets), is not notifiable.

 

[SeaGal]

Yes, another picture is attached showing the end of the garden (garden-rear.jpg). This gets light for most of the day but the tree does come into play later in the day. The garden office is planned for the end of the garden (30m from the house). I could do a canopy as well at the side of the office to give more roof space. That would be about 5m wide max and 2.5m high (ish).

Canopy sounds good then.

Yeah, I've read a lot about heating. I would be building the garden office from scratch so the insulation will be pretty extensive. I think it's better to look at offsetting the cost rather than running completely. A small mini-split or infrared radiator at 600w roughly, plus the other charging devices and LEDs.

Nice! Anything I can research?

These 2 threads for a starter...

Solis RHI 6K 48ES 5G Inverter Fox ESS LV5200 Battery - Charging limit ? and export to grid ...

Hi All, just had my Solis 6kw inverter and two Fox LV5200s installed too and noticed exactly the same problem others were having. Charge rate was maxing out at 1300w or 24A, BMS error stating low temp on inverter. Only way of knowing via app appears to be looking at what the charge current limit...

diysolarforum.com

Heating pads under battery

Alternatively, could i use 24V pad (30*30cm, 350W), but supply it with 12V power? This should halve the heat production right? That's still 175W at 12V, which seems like lots to me. I was doing 24W for twice as many cells. There really isn't any reason to try and heat things up quickly. You...

diysolarforum.com

I've seen lot's of Solis, they look good form the reviews. I'm assuming you have had a good experience?

Yes, pretty good, thanks - though I'm using my own battery interface software ?‍?
Plenty of threads on here about Solis inverters.

My main question on this is... can I adjust and play with the system? IE... I want to add another 4 panels. Can I do that or does every change need approval?

Only need approval for grid-tied, but that would only need updating if you change the inverter, not adding more panels.

Adding more panels doesn't change the inverters maximum output, which is all the DNO is concerned about. Look at a 3.6kW max inverter that is G98 compliant for simplicity and has a "fit-and-inform", rather than needing approval, approach.

So I try to limit that so I'm not banished to the shed ?
How does one do this?

SWMBO rules... remember that

Cheers for your detailed reply!!

YW

 

[efficientPV]

If you really want to learn about solar, try supplemental water heating. It has the lowest entry cost, will use 100% of the energy generated, everyone uses hot water, and is the only thig guaranteed to give a return on investment. If you think there will be a payback on this other stuff, I got London Bridge to sell you. Its challenging and you will gain insights to solar you won't get with these Buy It Now projects.

 

[bt77]

Tree - I know, I'm still thinking about it myself. I could only justify it if I have lots of panels if that makes sense. If I offset my carbon substantially through the panels then it somehow balances in my mind (in theory). It would be the difference between full sun all day and probably half a day's sun on the panels.

48v - Safety mainly. My initial research led me to 24v but I'd be open to 48v if it makes sense. 12v seems out of the question due to the length of cable runs. If I keep the tree the panels will be around 5 / 10 m from the invertor to get the best sun.

How's the Huawei high voltage system?

Huawei SUN2000 system is quite straightforward to install in terms of mechanical and electrical work. Software setup and configuration is a bit tricky but I got it running in couple of days. Couple months after installing the panels and the inverter, I got the LUNA2000 battery, the 5 kWh variant, more than enough for our evening/night load. So far so good after couple of weeks. Haven't used any grid power since adding the battery but it's still summer, so let's see if I'm gonna have to add more panels to my installation in fall and winter.

 

[Jourdain]

Canopy sounds good then.

Could be a good option for sure. I could start there and see how it all pans out. That way I can probably trim some branches to give maximum light to the end of the garden. I could build the panels into the design so that works as well. Interesting!

These 2 threads for a starter...

Very interesting indeed. I hadn't realized that LiFePO4 batteries had such an issue with temp. I know they need warmth but didn't realize the extent. I'll have to have a think about that. Maybe a small room that can get some of the office heat would be a good idea. That or we can replace the TV with a large battery bank! ?

dding more panels doesn't change the inverters maximum output, which is all the DNO is concerned about.

Good to know this makes sense. I haven't heard about the g98 approval so thanks for the insight. On the install, I am curious how much you can do yourself. With trades being £££ daily I'd be happy to install all the panels and run the cable etc (my dad and neighbor are really handy so I'll rope them in). I guess my question is, would they sign off if they haven't done the whole installation? maybe it's me being skeptical ?

SWMBO rules... remember that

???

 

[SeaGal]

On the install, I am curious how much you can do yourself. With trades being £££ daily I'd be happy to install all the panels and run the cable etc (my dad and neighbor are really handy so I'll rope them in). I guess my question is, would they sign off if they haven't done the whole installation?

As I mentioned above, electrical work will need to be done to IET BS 7671 standards by a competent person. You will also need to meet building regulations part P compliance, which means some work, such as installing a new circuit will require a sparky to install or a friendly sparky to sign DIY work off. Fortunately I've not had to install a new circuit, but have heard others on here have got a sparky to sign off for them - whether they were close friends or some £££ changed hands, I don't know.