Solar panels and battery - any real world reccomendations?

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Thank you all for your inputs, they have been most helpful. Lead times are definitely increasing by the day so don’t expect a quick turnaround from ordering to install. All due to supply issues and demand which are unlikely to abate anytime soon. Order placed just waiting for the subsequent survey and hopefully an amicable install date.
 
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This is the quote I have had through:

Proposal 1:
5.46kW Solar PV: 14 x 390W Panel 'Trina Vertex S' System PV Installation for a total cost of: £6,095.00 Inclusive of VAT
Proposal 2:
5.46kW Solar PV: 14 x 390W Panel 'Trina Vertex S' System + 5.2kW GivEnergy Battery PV Installation for a total cost of: £8,420.00 Inclusive of VAT

Not including accessories which they recommend:
Solaredge £800
Voltage Optimiser £600

I think we are going to be looking at moving house in 3-5 years so most likely not worth it and I wouldn't have thought there would be a direct correlation between the install cost and house value.
 
Soldato
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@ChrisD.

Those are pretty good quotes, but I wouldn't bother if you are planning on moving house, it's highly unlikely you'll get a return on your investment in that time frame.

Unless you are minted and care about the environment a lot, then go for it.
 
Soldato
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I guess its silly to think an install could be taken with the owner when they leave.

My ideal is put solar panels on Tesla car roof, it recharges everywhere stores into the battery and when you park up back home can supply the home + cheap recharge overnight also. Unfortunately I dont think a Tesla is big enough or solar efficient enough just yet, so maybe a freight truck driver could do it :p
 
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I guess its silly to think an install could be taken with the owner when they leave.

My ideal is put solar panels on Tesla car roof, it recharges everywhere stores into the battery and when you park up back home can supply the home + cheap recharge overnight also. Unfortunately I dont think a Tesla is big enough or solar efficient enough just yet, so maybe a freight truck driver could do it :p

Batteries can easily be taken, I guess. I think vehicle to load will be a big game changer in the future. You have a huge battery if you have an EV, the tech will let you use it for your house demands in the future imo.
 
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There's nothing to stop you taking a solar install with when you move house, except some complications, if it was a FITS install, then it won't be any longer, also not sure if you can get SEG payments on a second hand system not that they amount to much, and of course there is the cost of removing it and fitting elsewhere. As casper says, batteries are a lot easier to move.
 
Soldato
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It might increase the value of your house I guess, a bit.

I reckon if I was looking at properties, a house with a setup working solar array (provided not on one of these lease deals) would be a plus point.

So I guess in that respect you may get your investment back.
 
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For anyone looking at investing in solar and battery installations, have a look at the OpenEnergyMonitoring website. Lots of useful energy monitoring equipment and advice on solar, batteries, EV, etc.
We've had PV (4.1 kw system with a 3.6 kw inverter (solaredge) installed since 2018, but no battery. I've been looking into batteries as we end up exporting a lot of the energy we produce but at the current prices for battery installation Vs price of Kwh it just does not seem worth the cost of installing a battery. My calculations show that we wouldn't save the cost of battery install over 10 years at current energy prices (although if the kwh price hits £0.40 / kwh a battery starts to make sense). It might be because we are mostly working from home and have an ASHP for heating and hot water, so during the autumn to spring we already use around 50% of the solar electricity we produce.
The PVs on the other hand, cost us £7.7k to install, and we should recoup that in FIT payments and electricity savings in about 9-10 years. The panels have a 25 yr warranty so over their lifespan PVs offer a good ROI for us.
 
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For anyone looking at investing in solar and battery installations, have a look at the OpenEnergyMonitoring website. Lots of useful energy monitoring equipment and advice on solar, batteries, EV, etc.
We've had PV (4.1 kw system with a 3.6 kw inverter (solaredge) installed since 2018, but no battery. I've been looking into batteries as we end up exporting a lot of the energy we produce but at the current prices for battery installation Vs price of Kwh it just does not seem worth the cost of installing a battery. My calculations show that we wouldn't save the cost of battery install over 10 years at current energy prices (although if the kwh price hits £0.40 / kwh a battery starts to make sense). It might be because we are mostly working from home and have an ASHP for heating and hot water, so during the autumn to spring we already use around 50% of the solar electricity we produce.
The PVs on the other hand, cost us £7.7k to install, and we should recoup that in FIT payments and electricity savings in about 9-10 years. The panels have a 25 yr warranty so over their lifespan PVs offer a good ROI for us.

This is basically what our solar installer is saying, we are getting a 4.5kw system fitted early July, Mrs and I both work from home, so can obviously improve efficiency by running the dishwasher/washing machine etc, then we are getting a device that tops the hot water tank up with any excess generated through the immersion heater.

He was adamant a battery wouldn't be the best solution and the more digging and research I am doing seems this is right, or at least borderline to the point you'd want a years statistics so you can run the actual number rather than guessing.

You can always add a battery later on.
 
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This is basically what our solar installer is saying, we are getting a 4.5kw system fitted early July, Mrs and I both work from home, so can obviously improve efficiency by running the dishwasher/washing machine etc, then we are getting a device that tops the hot water tank up with any excess generated through the immersion heater.

He was adamant a battery wouldn't be the best solution and the more digging and research I am doing seems this is right, or at least borderline to the point you'd want a years statistics so you can run the actual number rather than guessing.

You can always add a battery later on.
Batteries are a tricky one at the minute as you are gambling on a few things if you go for one. If you add one later you have to pay VAT on the battery which adds a pretty significant extra cost to pay back before you get ROI you also really need both electric costs and battery cost to keep going up, seems a reasonable assumption at the minute given rampant inflation.
 
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Having to pay the extra VAT when retro fitting batteries later, plus inflation (energy price and battery and inverter increases) are good reasons to get a battery at the same time as fitting PVs.

If we were fitting PVs now, I'd be very tempted to also install a small (but expandable) battery, perhaps DC coupled rather than AC coupled.

For someone considering battery only installations, I suspect for most households it makes more sense to spend the investment on making the house more insulated and efficient than installing batteries.
 
Soldato
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I wonder how flexible installers are about putting it down as a solar install with a battery.

If you get teh cheapest smallest solar panel added, I mean, even if they didnt wire it, then the cost of that panel will far outweigh the VAT. Technically its a solar install?
 
Soldato
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For anyone looking at investing in solar and battery installations, have a look at the OpenEnergyMonitoring website. Lots of useful energy monitoring equipment and advice on solar, batteries, EV, etc.
We've had PV (4.1 kw system with a 3.6 kw inverter (solaredge) installed since 2018, but no battery. I've been looking into batteries as we end up exporting a lot of the energy we produce but at the current prices for battery installation Vs price of Kwh it just does not seem worth the cost of installing a battery. My calculations show that we wouldn't save the cost of battery install over 10 years at current energy prices (although if the kwh price hits £0.40 / kwh a battery starts to make sense). It might be because we are mostly working from home and have an ASHP for heating and hot water, so during the autumn to spring we already use around 50% of the solar electricity we produce.
The PVs on the other hand, cost us £7.7k to install, and we should recoup that in FIT payments and electricity savings in about 9-10 years. The panels have a 25 yr warranty so over their lifespan PVs offer a good ROI for us.
I came to the exact same conclusion which our installer also reinforced.

The useful economic life of battery storage is circa 10 years and at best the average house will recoup the cost over that time. This is money I could be investing and seeing a far better return on (even at a conservative 3% return I'd see a 34% return over 10 years). For battery storage to make sense I'd need it to pay back in 7 years or less.

On the other hand my PV setup will see 20 years for the panels, 10 years for the invertor but payback in 8 - 9 years. Allowing for a second invertor at year 10 I will still see an average annual return over 20 years of £400 or an overall return on investment of 80% over 20 years

To achieve this my setup prioritises any immediate electric demand for the house first, followed by a solar divertor to heat the hot water followed by charging the car. Anything remaining is then sold back to the grid. Whilst I could store this energy in a battery and reuse it there just isn't enough demand to make it worthwhile.
 
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SBo

SBo

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On the battery break-even calculations have you taken into account the winter months when supply from your panels will be poor, so force charging your batteries at a cheap rate c. 5p KWh overnight and using that during the day versus paying c. 40p KWh?
 

SBo

SBo

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Just checked Octopus Go’s available rate, 7.5p kWh.
Unit rate (04:30 - 00:30):
34.86p/ kWh
Unit rate (00:30 - 04:30):
7.50p/ kWh
Standing Charge:
43.12p/ day
 
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