Who has solar?

Be interested to hear about this too, it’s something we’re considering since the price hikes.
 
Just be aware that some solar installations can generate vast amounts of RF interference - electrical noise, which is naughty
 
I had a 10 panel system fitted in February
Total power generated so far is 835 KWH
I have a 3.5 kwh battery for storage , It is currently at 99% charge .
The full system fitted cost £9.500
Currently setting up with Octopus energy to sell my surplus at 7.5p per kwh
To make the most of the system you need to do all washing machine / dish washer energy using during daylight / daytime and use minimum at night / when its dark
You also need to have a south facing roof thats unobstructed , I am lucky as my garage roof points directly south ,
84FAF74E-6255-4395-9311-0EB692AF2478 by https://www.flickr.com/photos/150639903@N08/, on Flickr

Inverter

52DF6E52-8620-4171-BB59-601FC70F7CAC by https://www.flickr.com/photos/150639903@N08/, on Flickr

3.5 KWH battery

1E739F41-6B66-4EA1-882C-04452EA58544 by https://www.flickr.com/photos/150639903@N08/, on Flickr
 
My electric bill last month was £30 as it was the first half of feb before the system was installed , the next electric bill should be zero :):banana:
 
F1.2 said:
I had a 10 panel system fitted in February
Total power generated so far is 835 KWH
I have a 3.5 kwh battery for storage , It is currently at 99% charge .
The full system fitted cost £9.500
Currently setting up with Octopus energy to sell my surplus at 7.5p per kwh
To make the most of the system you need to do all washing machine / dish washer energy using during daylight / daytime and use minimum at night / when its dark
You also need to have a south facing roof thats unobstructed , I am lucky as my garage roof points directly south ,
84FAF74E-6255-4395-9311-0EB692AF2478 by https://www.flickr.com/photos/150639903@N08/, on Flickr

Inverter

52DF6E52-8620-4171-BB59-601FC70F7CAC by https://www.flickr.com/photos/150639903@N08/, on Flickr

3.5 KWH battery

1E739F41-6B66-4EA1-882C-04452EA58544 by https://www.flickr.com/photos/150639903@N08/, on Flickr
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Thanks. That's really helpful and the numbers are in line with what the salespeople are telling me which was one of my main questions :)

We're on the South Coast (literally in sight of France) so should be in an ideal position. I Unfortunately the South facing roof is shaded by a large chimney so the techs are suggesting a total of 16 panels on the west and east rooves. That should provide just over double what we currently use (until I can afford a Tesla). There's usually somebody in all day so we can run the big appliances during daylight.

Payback looks around 9 - 10 years at current prices but I think we can all guess what will happen to electricity prices in the near future.
 
lindsay said:
Just be aware that some solar installations can generate vast amounts of RF interference - electrical noise, which is naughty
Click to expand...
I hadn't heard of this - I'll look into it. I How would this affect me? Would RF disrupt WiFi? Or is it just more of a "they shouldn't be doing that" sort of thing?
 
I made an error in the fugue above
" Total power generated so far is 835 KWH "
That should be power exported to the grid 593 KWH
Self consumption is 291.5 KWH
 
The RF noise from some solar installations tends to affect frequencies in short wave - circa 2MHz upto maybe 20MHz, so AM broadcast bands and ham radio bands. Info: PV Noise
This probably doesn't bother most people but can be very disruptive to people within a radius of maybe 50m should they be users of those frequencies
 
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The panels are guaranteed for 25 years and guaranteed not to drop below 82% efficiency for 25 years , Inverter and battery 10 years , The panels are Hyundai
 
We have 8 panels on our roof since we don't have a big roof and have not suffered any RF at all. My computer gear is probably 15 feet away from the panels and 10 feet from the meter.
FWIW the panels don't just run on sunlight, they also work with natural daylight but obviously not so efficient.
 
We had a 16-panel (4kW) installation in 2014 which we combined with an air source heat pump for water and space heating (we have wet underfloor which helps). Total cost was about £13k and we estimated payback at six years (including FITs, Export Payments and RHIPs), which was a better return on capital than any other relatively risk-free investment. Our roof faces southeast and is partially shaded in the early morning in winter only.
The returns estimated by the installer were pretty close to reality. We live in West Cornwall with mains gas not an option, so our savings from changing water and space heating to heat pump were larger as LPG is roughly twice the cost. We also had a smart switch which puts our excess production into the immersion heater, so our water is fully heated before we start exporting.
More recently we bought an EV and our home charger (a Zappi) can also be set to preferentially use solar for car charging.
 
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Steep said:
Do you mean the battery can deliver 3.5kw for one hour total?
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Pass ? All I know is it can run my home from sun dow until sunrise and still have some reserve
 
Steep said:
Do you mean the battery can deliver 3.5kw for one hour total?
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Yes.

Average UK usage is 3,200 kWh per year so it would last a bit under 10 hours of average use.

Of course use tends to be very spiky so it should be a good buffer for night use except in the depths of winter. But if you stick a 2kw fan heater on, it will be gone in about 90 mins.
 
JonathanRyan said:
Yes.

Average UK usage is 3,200 kWh per year so it would last a bit under 10 hours of average use.

Of course use tends to be very spiky so it should be a good buffer for night use except in the depths of winter. But if you stick a 2kw fan heater on, it will be gone in about 90 mins.
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Cheers, I was asking particularly because I have an electric car to charge every night. 5 to 7 hours at 7kw
 
Suvv said:
I have considered solar panels but the payback period is too long for me.
Have you read the Money Saving Expert article? https://www.moneysavingexpert.com/utilities/free-solar-panels/
It has a link to the Energy Savings Trust calculator https://energysavingtrust.org.uk/tool/solar-energy-calculator/
They should give you a rough idea of cost and payback etc.
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Thank you, yes I've spent plenty of time on both those sites :)

Unfortunately the MSE article has a lot of "it depends". So for example their figures are for the middle of the country with "London around 4%" more power but no help for our sunny corner of the country (and even a 4% margin is a big difference here). It also quotes a 3kWh battery as £2,100. They are currently around £850 for a 2.4 which leads me to think that although the article was updated when the VAT changed, they haven't refreshed the figures which are pretty volatile ATM.

Energy Saving Trust has lots of sensible advice but their payback calculator doesn't take batteries into account and these make a huge difference.
 
Steep said:
Cheers, I was asking particularly because I have an electric car to charge every night. 5 to 7 hours at 7kw
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I'm looking at a system that generates about 6kw. So if it was 100% efficient (which it never will be) and nothing else is on (again, never true), it could charge your car in maybe 8 hours.

Assuming your car is about 45 kWh (7kw * 6ish hours), a full charge at average prices costs you about £13. Or "free" if you have solar :)

And yes, I need to start another thread on electric cars - what do you have?
 
JonathanRyan said:
I'm looking at a system that generates about 6kw. So if it was 100% efficient (which it never will be) and nothing else is on (again, never true), it could charge your car in maybe 8 hours.

Assuming your car is about 45 kWh (7kw * 6ish hours), a full charge at average prices costs you about £13. Or "free" if you have solar :)

And yes, I need to start another thread on electric cars - what do you have?
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Currently an MG5 company car. 48kw battery.
Trying to work out if the £10,000 odd cost of solar is a reasonable expenditure.
 
Steep said:
Currently an MG5 company car. 48kw battery.
Trying to work out if the £10,000 odd cost of solar is a reasonable expenditure.
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Thanks. One of the exact models I was looking at :)

A couple of days with Excel seems to confirm some of MSE's findings. If you live in the south of the country, have a decent size roof facing the right direction and plan to stay where you are for 8 years or more then right now, 10k solar is probably worth it. Having an EV increases the benefit - if you can fuel your motoring via spare solar rather than petrol you can save quite a chunk of your fuel bill. When I was driving every day I probably went through £40 of petrol a week which is £2k. If you can fully replace that (and that's a big if) then your payback could be 5 years.

There's a lot of complexity around batteries though - a battery will tip the balance but they don't last as long as solar panels.

As electricity prices rise that benefit will creep north.
 
I've had solar PV, no battery, for over 5 years now. W-E facing roof, 5 on each side. Install size of 2.9 kW-peak but would only produce 1.6 kW in most ideal conditions due to roof orientation, so not able to charge EV.

I get feed-in-tariff, so calculations would be different. It costed £7,000 to install. Projected ROI was around 11 years. But I expect I see break even point in next 2-3 years due to higher leccy price and my solar powered crypto mining efforts. Per year, I get ~£400 in FiT payment, I self consume 1400 kWh over last 365 days, which translates to saving of ~£350 on pre-April 25p/kWh day-time prices (EV tariff). Then there was ~£400 mining payout during highest last year. Plus crypto holding of £1000+ over previous years mining.

I'm considering a separate home battery system. My goal is to use over 90% of solar production by having battery as buffer, and also time-shift other house consumption to the cheap EV tariff periods.
The system Allen F1.2 posted looks like an integrated solar-battery system. Unfortunately I cannot do that because the FiT payments are calculated using an AC meter, after the solar inverter. So I cannot add battery before the meter. I have to do it less efficiently by getting another inverter with the battery as separate unit, tied through AC mains.

Steep said:
Do you mean the battery can deliver 3.5kw for one hour total?
Click to expand...
There's 2 main metrics with battery: power (in kW) and energy (in kWh).

I think 3.5 kWh means the battery can store 3.5 kWh of energy.
The photo of battery looks like it's just a battery, the Growatt controller/inverter do everything else. So the power figure would be dependent on the capability of the inverter inside that box.

JonathanRyan said:
I'm looking at a system that generates about 6kw. So if it was 100% efficient (which it never will be) and nothing else is on (again, never true), it could charge your car in maybe 8 hours.

Assuming your car is about 45 kWh (7kw * 6ish hours), a full charge at average prices costs you about £13. Or "free" if you have solar :)
Click to expand...
It wouldn't work like 6 kW * 8 hours = 48 kWh. Solar production is a curve. You'll need to get something like Zappi to vary EV charge rate based on solar production. But I'd still favour 7-8p EV tariff and use solar to reduce expensive daytime consumption. (+ battery to timeshift all consumption to the cheap period)

This was last Sunday, for example. We were away for the morning until mid afternoon. Then I fired up bouncy castle for an hour or so without incur a cost. But late afternoon cooking used 2kWh from the grid.

1649922778975.png
 
I have an electrician friend who resides about a mile from me. His solar panels are not producing any noticeable RFI, but the installer explained that screening had been used to counter the problem.
However the panels have introduced a another problem. Flying rats nest under them and they carp etc. everywhere.
 
Oh yes, I also spent £500 to prevent birds getting underneath. Also some money on monitoring and home automation hardware, more of a hobby than necessity.

Home | OpenEnergyMonitor

openenergymonitor.org openenergymonitor.org
The screenshot you see comes from this. I have DIY'd the hardware and using their software on a Raspberry Pi. Then on a server running Home Assistant VM to interface with hardware and do home automation.
You can also buy OpenEVSE an open source alternative to Zappi, supported by this software.

In the screenshot, you can see a jump in consumption at ~8am and ~4pm, they were PC desktop automatically turning on to start mining. The 1:30pm spikes were putting on a lower power kettle to store some hot water.

If you have hot water tank, it's a great use of solar excess. There are many established products for this.
Another good use of solar excess is dual-fuel towel radiator. I was trying to install it last weekend but bought the wrong fitting, I hate doing plumbing...... Then use simple smart plugs through Home Assistant to turn on/off.
 
I have an app on my phone called ShinePhone does all my monitoring .
 
wyx087 said:
I've had solar PV, no battery, for over 5 years now. W-E facing roof, 5 on each side. Install size of 2.9 kW-peak but would only produce 1.6 kW in most ideal conditions due to roof orientation, so not able to charge EV.

I get feed-in-tariff, so calculations would be different. It costed £7,000 to install. Projected ROI was around 11 years. But I expect I see break even point in next 2-3 years due to higher leccy price and my solar powered crypto mining efforts. Per year, I get ~£400 in FiT payment, I self consume 1400 kWh over last 365 days, which translates to saving of ~£350 on pre-April 25p/kWh day-time prices (EV tariff). Then there was ~£400 mining payout during highest last year. Plus crypto holding of £1000+ over previous years mining.

I'm considering a separate home battery system. My goal is to use over 90% of solar production by having battery as buffer, and also time-shift other house consumption to the cheap EV tariff periods.
The system Allen F1.2 posted looks like an integrated solar-battery system. Unfortunately I cannot do that because the FiT payments are calculated using an AC meter, after the solar inverter. So I cannot add battery before the meter. I have to do it less efficiently by getting another inverter with the battery as separate unit, tied through AC mains.


There's 2 main metrics with battery: power (in kW) and energy (in kWh).

I think 3.5 kWh means the battery can store 3.5 kWh of energy.
The photo of battery looks like it's just a battery, the Growatt controller/inverter do everything else. So the power figure would be dependent on the capability of the inverter inside that box.


It wouldn't work like 6 kW * 8 hours = 48 kWh. Solar production is a curve. You'll need to get something like Zappi to vary EV charge rate based on solar production. But I'd still favour 7-8p EV tariff and use solar to reduce expensive daytime consumption. (+ battery to timeshift all consumption to the cheap period)

This was last Sunday, for example. We were away for the morning until mid afternoon. Then I fired up bouncy castle for an hour or so without incur a cost. But late afternoon cooking used 2kWh from the grid.

View attachment 350114
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Yes, good point on the curve. Of course you'd never get close to 100% sustained over 8 hours.

I've askari had the quote amended for bird netting. Allegedly the panels are too hot for them to nest but I totally don't trust it seagulls.

And that reminds me, I was looking for an excuse to get a raspberry pi.... It could control the brewery as well as the solar.
 
Years ago they installed Owl Intuition as my solar monitoring system, but a few years later, Owl started charging a subscription. I said "fine, I'm going to build my own monitor system, with blackjacks....."

The netting was installed due to pigeon noises I hear on my roof and seeing pigeon going under it. They are probably right for hot sunny summer's day. But during overcast spring days, when pigeons are actively nesting......

Speaking of heat, do remember PV works most efficient at ~20c. They do heat up when producing. You'll get less peak power during hottest summer days. More of a problem for trying to manage load to use all the excess. Overall production over the whole day would still be good because longer time at high output and more ideal sunshine.
 
We got hot water heating panels soon after we moved in and they give us a fair bit of free hot water for most of the year. In a cloudy part of the world though, so we still need back-up, especially in winter.

About 5 years ago we took the plunge with Solar PV's . Only 14 panels due to the size of the roof. It cost about 5k including the inverter and all the wiring and piping. I think we get about £800 p.a back in FiT payments, which were still reasonably generous in those days. One thing to remember is that if you have an outbuilding or extension with a low roof the installer doesn't need to hire scaffolding to fit the panels which should cut down on the cost. As we are also in a very windy place we have twice had to pay to have the panels refitted after storms, although the first time was under guarantee. Other than that the whole set-up has been trouble free.
 
Would like to do it but unfortunately our house is not suitable, wrong orientation and no garage to locate a battery or any other gubbins.

Out of interest, is there still funding/loans available to help with this or is that a thing of the past now making the option to save money only open to those who already have some? [/facetious]
 
bass_junkie83 said:
Would like to do it but unfortunately our house is not suitable, wrong orientation and no garage to locate a battery or any other gubbins.

Out of interest, is there still funding/loans available to help with this or is that a thing of the past now making the option to save money only open to those who already have some? [/facetious]
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As far as I know, the only help is vat free installation. There are some grants for ground source but that's a whole different thing.

Yes, I get the whole "rich save money" thing. It's not a great way to run things but since it's so, I may as well look into it because I can afford it.

As you mention, just having money isn't enough. You also need a suitable roof and space. Also, to own your home, there are no great options for renters or flat dwellers in the new world of green power.
 
I’m keeping an eye on this thread as we are debating a solar installation. Some useful info in this thread. Would need to get planning permission as I live in a national park area but SSW facing roof so should be an efficient system.

We don’t use much electricity in my house so could probably get by with running the house on what we generate.
 
I'd really like to start out on this journey, but unsure where to start. I'm very keen to enure that I avoid cowboy installers etc.

I'm particularly interested in a solution that can be extended as circumstances change..... addition of EV, inclusion of air source heat pump.

Where did people get advice? I understand basics, but don't feel qualified to design an integrated energy system. I'd really like to speak to qualified engineers that can design a suitable solution starting with solar panels.

Any pointers?
 
@4tea2
make sure they are MSC certified installers, you will need their certificate, I am with Goodenergy for FIT payments, others may vary as to how good they are,
I don't know about heat pumps and so on we just have the panels to save electric and get a bit back from the surplus.
 
4tea2 said:
I'd really like to start out on this journey, but unsure where to start. I'm very keen to enure that I avoid cowboy installers etc.

I'm particularly interested in a solution that can be extended as circumstances change..... addition of EV, inclusion of air source heat pump.

Where did people get advice? I understand basics, but don't feel qualified to design an integrated energy system. I'd really like to speak to qualified engineers that can design a suitable solution starting with solar panels.

Any pointers?
Click to expand...

Yeah it's a tough one. Practically any fitter will "design" you a system but obviously they will base it around what they want to sell you and how much they think they can get. There are lots of regulations - obviously I wouldn't deal with anybody who didn't have MCS certification with an insurance backed warranty.

One thing that I'm really noticing in my research is that right now solar thermal (heating hot water in tubes) probably isn't worth it. It costs about 4-5k to fit a system to save up to whatever you pay to heat water. However, an iBoost and immersion heater probably is worth it if you have a hot water tank. Fitted cost is around £4-500 (less if you already have an immersion) and you can use this to heat water using PV. Even if you added another couple of panels to provide the spare capacity it's still about 20% of the price of solar thermal.
 
JonathanRyan said:
Yeah it's a tough one. Practically any fitter will "design" you a system but obviously they will base it around what they want to sell you and how much they think they can get. There are lots of regulations - obviously I wouldn't deal with anybody who didn't have MCS certification with an insurance backed warranty.

One thing that I'm really noticing in my research is that right now solar thermal (heating hot water in tubes) probably isn't worth it. It costs about 4-5k to fit a system to save up to whatever you pay to heat water. However, an iBoost and immersion heater probably is worth it if you have a hot water tank. Fitted cost is around £4-500 (less if you already have an immersion) and you can use this to heat water using PV. Even if you added another couple of panels to provide the spare capacity it's still about 20% of the price of solar thermal.
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Yes, I agree that if you are planning to fit PV panels it is probably not worth having solar water heating panels for the reason you suggest.
 
My panels stood up to 82 miles an hour winds , All still in place.
 
Steep said:
Currently an MG5 company car. 48kw battery.
Trying to work out if the £10,000 odd cost of solar is a reasonable expenditure.
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I've got an Audi Q4 etron company car and a 7kw home charger.
There's a rapid charger 6 mins from my house which is currently free.
I've done just over 3000 miles and only spent £70 of my own money on charging....and I've got £125 to claim back for business miles :cool:
The part of my roof that faces the sun has a big dormer on it, so Unfortunately solar is not really an option for me....:(
 
Unfortunately for me, local rapid chargers are 30p per kwh and my home rate is now 28p.
I get mileage payments for the car and the company is pretty good in that they now adjust to match my home rate.
 
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