Solar panels and battery - any real world reccomendations?

We've been away for the last few days and we've been making about £1 - £1.50 profit every day factoring in standing charge.

Even our small 5.2kwh (well supposedly) battery is just about lasting the night.
 
Mercenary Keyboard Warrior said:
Looks nice.
Solaskirt impacts performance a smidge but does look good.
That top right panel is going to be a prime target for bird poop.

In regards boxing in, consider a small heater (like a tube heater) if the batteries have no heating.
50mm of PIR and a small heater should keep them running well in anything but super cold weather.
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To be honest, happy to take a slight performance hit over looks and wildlife! We are rife with squirrels and my mate has had no end of issues with the little critters moving in under his panels.

We dont tend to get them sitting on the aerial, and there was minimal poop on the roof prior to fitting. They tend to favour the chimney pots. Its quite a flimsy aerial so they just dont bother.
 
Gav_r26 said:
Couldnt get any more on really, without putting them on the rear roof which is north west facing, which didnt really add up.
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You'll be surprised how well north west panels work, quite a few people on here with NW, and I'm just installing 12 WNW panels.

Take a look at this guy, his panels are NW, although he's on the south coast, Southampton I think

 
Ron-ski said:
Take a look at this guy, his panels are NW, although he's on the south coast, Southampton I think
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Having watched the video, it seems to me it was more a case of his south East panels dropped to the level of the North West ones due to the cloudy month, rather than the North West ones performing really well. But yes its impressive how much they do generate even on a cloudy day so it would be potentially worth getting 9 panels ish on there at a later date. Would depend on the costs though.
 
Gav_r26 said:
Just had a SolarEdge system fitted. 12x 450w panels and a 10kW battery. Couldnt get any more on really, without putting them on the rear roof which is north west facing, which didnt really add up. South is pretty much where the first photo is taken from. Early days but seems to be making a good dent into our usage! We are above average electricity users but below average gas users thanks to the woodburners. Need to box the battery / inverter in on the corner of the patio, firstly for asthetics and secondly to keep the UV and heat off of them. Happy with the install, and the Solaskirt helps blend it to the roof IMO.

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How much did that system cost you, think our house will be able to take similar amounts of panels and looking at 10kw battery.
 
Gav_r26 said:
Having watched the video, it seems to me it was more a case of his south East panels dropped to the level of the North West ones due to the cloudy month, rather than the North West ones performing really well. But yes its impressive how much they do generate even on a cloudy day so it would be potentially worth getting 9 panels ish on there at a later date. Would depend on the costs though.
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The issue of course is winter generation, they are basically useless for 3 months of the year arguably when you most need it. I still think it makes sense to do it on a new install since panels are cheap, just maxing out all roof space has to be the default choice.
 
200sols said:
The issue of course is winter generation, they are basically useless for 3 months of the year arguably when you most need it. I still think it makes sense to do it on a new install since panels are cheap, just maxing out all roof space has to be the default choice.
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If money is no object, then yes you are probably right as the aditional cost of panels and optomisers at around £110 per panel and maybe £1k extra on a larger inverter. But sometimes you have to draw the line somewhere.
 
200sols said:
The issue of course is winter generation, they are basically useless for 3 months of the year arguably when you most need it. I still think it makes sense to do it on a new install since panels are cheap, just maxing out all roof space has to be the default choice.
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I wouldn't say useless, they will produce, just not as well as the summer, and what you bank in the summer helps towards winter.
200sols said:
Yeah, when you have no roof left :cry:
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When you run out of roof space, start on the walls.
 
Firstly, thanks to @DRZ for some intial direction in a seperate thread. Bringing my request in here with some lower level detail to help get direction on what is worth my while.

So first up, my usage. In the region of 8200kwh a year, broken down into:

SUMMER MONTHS AVERAGE: 575kwh / 19.16kwh/day - Through HUGO I estimate that my daytime usage avereages 7.66kwh and evening 11.5kwh.

WINTER MONTHS AVERAGE: 1000kwh / 33.33kwh/day - Meaning that around an additional 14.17kwh/day is used for the heating, for around 4 hours per night 18:00-22:00.

In addition to the electric radiators, my hot water is supplied via a 7kw thermal battery.

According to my HUGO app data, at the times this charges in the day currently, we consume around 3.8kwh of electric per day heating the hot water. This is bang on consistent with the tech spec sheet estimate. This battery can obviosuly be charged at any time of day as a full charge gives us enough for 3 showers and all the handwashing we need for a full day. The electric radiators obviously are time critical in terms of heating the house in the evening during winter. I work from home, but I tend not to bother putting the heating on during the day in winter as I just wear a warm fleece.


AIMS:
We plan to move house - If it were the forever home we would go whole hog powerwall, micro inverter etc, but not for this purchase as will be too much cost. What we want is to get some pay back over a few years and hopefully have it wipe its face with that combined with the house value and more importantly saleability of the house - So FTB (who this house would appeal to) are not put off by the EPC rating and electric heating costs.

I have already calculated that to power the heating for a whole night, I would be 3x 5.3kw batteries. This is not an option as too much cost.

I can fit 10 panels on the SSW facing part of the roof, so 4.3 / 4.4kw sysytem. There isn't any shading and given my time frame for moving I don't see the point in forking out the extra for micro inverters. I don't expect many buyers are going to be concerned over and above the fact it has solar and the monthly bill.....

My initial thought was panels, battery to charge during the day to power the radiators on the night, but having done all the research I can see this is not achieveable in the winter. Projections for generation are 3800kwh p/year.

So I am trying to establish the most optimum spend for my scenario. I am open to chaning my supplier to be able to charge things of a night and of course get the export, but I am not predicted to export much (as much as 94% own usage on some of the quotes).

I think I have done most of the ground work, I just can't quite get to the end point of what is the best course of action.

Some quotes I have had:

OPTION ONE:
10x 430w JA Panels (4.3kw)
Sunsynk Hybrid Inverter 5kw (up to 45 days for application)
OR Sunsynk Hybrid inverter 3.6kw - immediate install
5.32kw Sunsync battery
Bird mesh
Total install cost £7499

OPTION TWO:
8x 440w JA solar monocrystalline panels (3.52kw)
Enphase IQ8 microinverters
Enphase 5kw battery
Total Install cost £8790

OPTION THREE:
10x430kw JA Panels
5kw Sunsynk Hybrid Inverter
Bird Mesh
NO BATTERY
£6199

OPTION FOUR:
10 x Longi HiMo6 435w all black mono panels.
10 x Enphase microinverter IQ8AC.
1 x Enphase Envoy-S metered version for local and remote monitoring (via your WIFI).
1 x Enphase IQ5P battery bank. 3.2kW charge / discharge rate with 5kWh storage
capacity.
£9695
+£220 Bird Mesh

OPTION FIVE:
10 x Longi HiMo6 435w all black mono panels.
1 x EcoFlow PowerOcean 3.68kW Hybrid inverter.
1 x EcoFlow PowerOcean 5.1kWh LFP battery
£8069
+£220 Bird Mesh

I think the bit I need to get my head around is how to best use what setup, utlising what tariffs, for the least negative return over, say a three year period. Any help greatly apprecaited as obviously every company all just wants to tell me why thiers is better than everyone else and starts to shy away when I give them this low level of detail on my usage as they don't know what to reply to me :cry:
 
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honestly i think a token 5kwh battery for your use is a bit pointless, you should be looking at systems with 10kwh at minimum or ideally 15kwh, but that would add another £2-4k to the system costs
how much of your energy usage are you able to shift to after midnight?

for example, for my use scenario, i use on average about 6-7kwh/day (PV + grid)
so i have a 4.4kwp system with a 10.2kwh (9.2 usable) battery
i charge the batteries overnight with an EV tariff and shift 95% of my grid use to the off-peak tariff (32p peak, 8p off-peak between 0000-0700 via eon)
my solar exports are 16.5p via eon as well
i would save about £400/year (£30ish/month) in electricity costs and my exports would net me about £500/yr, so my ROI is about 8 years ish
 
Out of those options, with a flat tariff and an understandable reluctance to invest in a battery I'd probably lean toward something like Option 3 but with a regular inverter not a hybrid to keep the costs right down. ToU tariffs would help you enormously even without the solar aspect, then a battery would be hugely beneficial even without the solar panels and then the solar is just the cherry on top. The issue there is getting access to them. Without an EV you can't get on Intelligent Go, without a heat pump you can't get on Cosy Octopus, without a GivEnergy battery system you can't get on Intelligent Flux etc. I think a switch to Agile would be ruled out by the times you're using the most power unless, again, you had a battery to time-shift all of that usage.

Ultimately I think it comes down to your usage, especially winter usage, being way too high for the size of roof you have combined with your short planned ownership duration... You might find better ROI from finding ways to use less power - insulation, heat pump to replace the electric rads etc might prove way more cost effective than solar. I could be wrong though :)
 
DRZ said:
The issue there is getting access to them. Without an EV you can't get on Intelligent Go, without a heat pump you can't get on Cosy Octopus, without a GivEnergy battery system you can't get on Intelligent Flux etc. I think a switch to Agile would be ruled out by the times you're using the most power unless, again, you had a battery to time-shift all of that usage.
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octopus may be the best and most flexible, but eon are also pretty good (and cheap) too
if not able to hop on octopus tariffs, and as a current user of eon (both for the ev tariff and SEG), i would suggest to seriously consider eon's ev tariff
(i don't think they check if you have an ev...so it's basically an eco7 tariff)
 
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You can go on Eon Drive Next with just a battery, 7p 00:00-07:00.


Option one looks like the best bang for the buck. Charge the battery and the heat store to 100% daily in the cheap period and only use it to fill in when on peak time electric. Ideally you need more batteries which can easily be added to that system. Ideally you also want to run your radiators for a bit in the cheap period also as it will stop the house from cooling so much before they come on again in the evening. You will use more energy but it will be cheaper and that should be the aim.

Check if the batteries are 100% depth of discharge or 90%, less than 100% means the usable capacity is only XX% of the stated capacity, there are also conversion losses to consider.
 
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BDEE said:
I have already calculated that to power the heating for a whole night, I would be 3x 5.3kw batteries. This is not an option as too much cost.
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Surely you need to know the whole system cost first, you can get 10 panel system with a hybrid inverter fitted for £5k, and then just add a 15kWh battery for £2.5k yourself, taking you to £7.5k.
 
I didn't know that about the E.on tariff, I assumed (clearly incorrectly) that you needed an EV. In that case, a token battery is definitely VFM because of that 7p rate which is a 12.5% discount on your base load if nothing else, plus ~4kWh of offset saving you ~70p/day.
 
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Realistically I can move all of the water battery charging to night time and things like washing / dishwasher, but one key piece of info I should have included is that I keep reptiles, which need heat / light going during the day. THis is about 330w of lighting / heating running about 8hrs per day, so it isn't HUGE amounts but it does add to the daytime load.

The washer and dryer (heat pump) are on daily (lots of dogs as well as mrs being a dog walker so lots of towels to clean) but no issue running these at night. The rest of the day time spend is work laptop, monitors, TV, air fryer, PC etc.
 
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