Plug in solar

Scot_39

https://forums.moneysavingexpert.com/discussion/comment/81967333#Comment_81967333

I'm glad you've got a strong garage to use these things.

Google AI says these things need ballast - a lot of ballast - if its correct

"Ballast Weight: Recommended ballast weight is generally between 60kg and 120kg per tray, depending on wind loading calculations."

I sometimes put ballast in my wheelie bins if empty ahead of stormy weather - 8-10kG - as their at risk of damaging cars - And i dont know how big the sand bags that roadworkers throw over their sign a-frames - I guess often not heavy enough given how mny I see blown over sometimes - but 60-120kG - i guess on a one tray for one panel basis - sounds like their expecting some pretty big wind forces.

Martyn1981

We had our wheelie bin, in a storm, reverse out of the alcove by the porch, travel uphill, reach our 3 week old Tesla, open its lid,then try to beat the car to death with the flapping lid.

Now fitted a bracket to the wall, and stretch a bungie cord around the bins. But closing gates and bolting horses spring to mind.😁

Regarding small PV arrays, we built a ground mount in 2024. Whilst this wasn't for plug-n-play, it would fit the role as just over 2kWp. So with a suitable hybrid battery, such as the Ecoflow Stream Ultra X with 4 MPPTs, it would work well, trimming panel capacity down slightly from 4x 530Wp to say 450Wp.

Pretty cheap, less than £500 all-in, including a day's labour assistance from a 'fence-man', with lots of experience digging out and setting posts in the ground with postcrete or similar. May have gone overkill using 4 inch timber (4x4 and 4x2), but only a small cost difference. Has 3 coats of Blackjack on it, as I assume it will get damp(er) being shielded from the sun.

Pitch was determined by the size of panels (2.1m tall) and available space, but came in within 2d of target 60d pitch for winter optimizing.

Alternatively, for folk pondering. You could use a fence. The concrete one behind the set up, has 'planks' that slot in, so easy enough to insert brackets into it, to hold panels either vertically, or with at least a bit of slope.

Taking things even further, but probably not plug-n-play, you could now use panels as fencing. I think bi-facial panels on an E/W orientation may even surpass panels on a south orientation, but will depend on shading.

Then there's wall mounted panels, which are now permitted development (but double check local planning rules), and can look quite nice.

Martyn1981

Thinking about that fencing idea, panels like these would be pretty good, and with a 1 to 2 foot barge board, would give 5 to 6 foot fence height. And no painting or maintenance!

QrizB

The concrete one behind the set up, has 'planks' that slot in, so easy enough to insert brackets into it, to hold panels either vertically, or with at least a bit of slope.

Balcony brackets could work well on a fence like that.

JKenH

https://forums.moneysavingexpert.com/discussion/comment/81967900#Comment_81967900

I like that - it looks a good solid job. There’s a useful bit of dry storage there as well. It would keep a micro inverter and extension lead out of the worst of the weather.

I wonder when someone will construct a whole shed out of solar panels bolted to a timber frame.

I am also looking forward to seeing @Coastalwatch’s solar carport when it is finished.

tfhnota

Conceivably you could build most of the roof with plastic solar trays that are designed for new builds (and replace slates/tiles) and then fit the solar panels to the trays, you just need some wooder members to support the trays.

QrizB

I wonder when someone will construct a whole shed out of solar panels bolted to a timber frame.

Something like this? Timber-framed shed with 6x500 watt panels as roof.

https://www.youtube.com/watch?v=dIiPKw_YQ04

Martyn1981

https://forums.moneysavingexpert.com/discussion/comment/81968206#Comment_81968206

Yep, on the green forums, loads and loads of sheds, chicken coops, log stores and like me a 'ladder store', with PV on the roof, as they don't need planning permission. Whereas, weirdly, a ground mount needs PP if over 9m2 or 3m on any one side (12m2 I think in Scotland). And for 'genuine' shed builds, a bit of forethought having a mono-pitched roof facing south(ish) makes great sense. Just build a taller north wall, shorter south wall, and slope down. Or dual pitch E/W and shallow. As mentioned by tfhnota, you could use PV roofing trays, or maybe polycarb as the roof underneath, or just the PV, and use rubber T-pieces to fill in the panel gaps, if being fully water tight isn't essential. For the canopy over my back door, two panels landscape, the gap is central and over the backdoor step. So I just put a piece of clear greenhouse glass tape over the gap. It lasts for years before the UV gets to it, longer if taped from underneath, but for a shed roof, with two dimensions for rain to catch, from above would work better.

Surprised the ground mount rules weren't relaxed a bit, when wall mounted became PD. Would have thought wall mounted was more controversial.

Seen one that looks quite a bit like mine, but maybe 25% larger on the side. Then panelled in with fence timber on the rear, and a small door on the side - used to store garden furniture in the winter, and again, not a ground mount.

Fingers crossed, attached to fence panels, or as fence panels, will come under wall mounted, but who knows?

lohr500

https://forums.moneysavingexpert.com/discussion/comment/81967799#Comment_81967799

Fortunately the garage roof supporting beams are massively overkill, so the weight shouldn't be a problem.
And we have a tractor with a front loader so lifting ballast to the roof height shouldn't be too challenging.

The data sheet says suitable for wind speeds up to 60m/s which equates to 134mph.
Apparently in November 2021 we saw 110mph above Settle in North Yorkshire which is far more exposed than where we are.

The trays only give an inclination of 18deg which isn't optimal for the panels, but I suspect this is to improve the stability in high winds. Our roof has a pitch of 4deg, so the effective inclination will be 22deg.
The PVGIS solar tool tells me I should use 35deg inclination for the best output at our location. It also tells me they should be orientated at 16deg east of South which I can achieve.

With a 35deg panel inclination the model calculates 700kWh output p.a.
At 22deg it calculates 689kWh p.a so not a massive loss of output.

The model may be optimistic though. Only time will tell.

This morning I checked both of the panels I got yesterday with a voltmeter.
In very overcast skies and with the panels pointing to the East, I got an open circuit voltage on each of 46.8 volts. The label on the back of the panels states an open circuit voltage of 49.8 volts.
No idea if the 46.8 volt reading is good, bad or indifferent as solar is a whole new game to me.
But the fact that they are both giving the same reading gives me some confidence that the panels are OK.

So far the build cost is coming in at £334. £100 for the panels, £93 for the plug-in micro inverter, £116 for the tub trays and £25 for an 8m set of DC extension cables with 6mm cores to link the panels to the micro inverter.

The trays have really pushed up the cost but as I mentioned before, I don't want to drill through the garage roof or compromise on the integrity of the mounting.

Once all the bits and pieces arrive, my plan is to temporarily set the system up at ground level on the drive next to the garage. I can then check that it does what is says on the tin before installing it on the roof.

QrizB

£25 for an 8m set of DC extension cables with 6mm cores to link the panels to the micro inverter.

It's probably too late for to save you any money, but for short cable and two panels in series you'd be OK with 4mm, or even 2.5mm.

The Hoymiles spec sheet does put you very close to the maximum voltage if you're running a two-panel series string (2 x 49.8 = 99.6V, max per spec sheet = 100V). You'll be over the maximum current if you were thinking of running them in parallel.

https://www.hoymiles.com/uploadfile/1/202509/745cb64a84.pdf