overall cost of installing Solar panels

[MrJuice]

OutInTheShed said:

I think the system is being shaken up.

It's unfair to dismiss the costs of providing a grid, metering and billing services etc as 'zero effort'.
All that infrastructure costs real money.

My friend runs a company that buys power from commercial renewable generators like the farmer with pv or wind on their land. He aggregates and sells to commercial customers.

The infrastructure, metering etc is all done by third parties. My friend makes the lion's share.

I agree that selling one's power from their roof pv panels on the cheap is resulting in long pay back and low take up. It needs reform

[Evoluzione]

Tobermory said:

rustyuk said:

So your current electricity bill is more than £2300 a year?

Is anyone 100% self-sufficient with solar? If not then your current bill might need to be much more than £2300 to hit the 7 year timeline.

Yes the current use (before getting an EV) is around 6600


The key to understanding this is that the prime consideration is to install the most cost effective system you can while still using all the electricity generated and trying not to have to sell any of it on.

You can’t be self sufficient because you just can’t make enough in winter but you make too much to use in the summer. If you spec a system to provide enough in Winter (and you have enough roof space for the 40kWp or so you would need) you will produce far too much in Summer and have to sell it in at a pitiful rate. You wouldn’t get permission from the DNO for such a system anyway

BUT if you add in an EV you can soak up all extra and effectively use all of your production over the year. Of course you will end up buying off the grid to fuel the EV and provide some domestic but you would be doing that anyway without solar panels. Essentially you need increase your Summer electricity usage enough that you can use the full amount produced even in Summer


The key to make a solar installation pay back is not to aim to become 100% self sufficient year round but instead to make sure that you buy the most cost effective system (kWp per £ capital invested) that you can still use all of the power from in this way. You then avoid having to sell back your ROI at 5-15p per kWh which is too low to make sense.

There will be an upper limited dictated either by your roof size or the amount you need to charge your car in Summer to use your excess.

But using this approach you can make solar pay back in 7 years at the current cap and 4 years at the predicted April 2023 rate, yes.

(Note when I say increase your electricity usage, I mean in a good way such as converting from ICE to EV, I’m not advocating everyone going out and buying a hot tub!)

Edited by Tobermory on Sunday 30th October 09:21

As you point out you haven't factored in the cost of your EV. You're also going to have to do a lot of mileage every day of the week to use all that electric, then how will that work out in Winter?
You're spending a lot of money to try and save very little. Also you're selling your scheme for the wrong reasons, you aren't mentioning the fact that system will be in place for the next user to benefit from and the ecological advantages.
The improvements to you and your families mental health too.

[WyrleyD]

Our district council sent around a letter a few months ago to gauge the interest of group purchase of solar panel installation.

Just had the results and the quote for us:

15 panels installation is £9089

7 kw battery storage is £5180

Annual saving with battery is £663

So, a very long payback period and I will probably be long gone from this world before the cost is recovered (that's as long as the price rises are not absolutely astronomic).

Edited by WyrleyD on Sunday 30th October 12:38

[dmsims]

Those Solar together schemes (and you need to read the feedback!!) are always more expensive than going to the same supplier directly

[anonymous-user]

Evoluzione said:

As you point out you haven't factored in the cost of your EV. You're also going to have to do a lot of mileage every day of the week to use all that electric, then how will that work out in Winter?
You're spending a lot of money to try and save very little. Also you're selling your scheme for the wrong reasons, you aren't mentioning the fact that system will be in place for the next user to benefit from and the ecological advantages.
The improvements to you and your families mental health too.

Absolutely, I should have said that my main reason for doing this is to be more environmentally friendly. I have been wanting to go solar for several years but it has just not made sense financially. I only really want it to be cost neutral over its lifetime, but it's much better than that in fact.

Regarding the cost of buying the EV, again absolutely this makes no sense financially, but I am buying one anyway, the decision to do this is not dependent on having solar panels though they help synergistically. I'm one of those weird people who find the driving experience in an EV better for the daily commute, and my use pattern makes it very unlikely I will ever have to charge away from home. (It's 2.6 m/kWh btw). There are very few off peak tariffs available now so that's not really an option. If they return then yes it changes the calculations and a smaller system might be better I agree.

It's a very complex overall calculation and you can quickly get into headache inducing circular arguments and double counting, so I'm happy to learn if my logic is wrong, but essentially I think it all comes down to now having to export energy and receive a pittance in return. The most difficult bit of this is using the 'excess' energy in the Summer daytime.

I WFH for 3 days a week and commute 70 miles (round trip) on alternate days. Now I appreciate this is an unusual pattern, but it means I can run an EV on alternate day daytime charging during the Summer to do just that. In the Summer i would only charge the EV during the day (using a Zappi charger which allows you to schedule the charging) There would be some exporting during the peak Summer months but relatively little this way.


This is why I think for me I could expect payback in 7 years, or even less if the elec price goes up in April. My yearly mileage is 8,000 miles and this equates to 20 kWh per day on alternate days. This is an ideal way to soak up the Summer peak and is why I am reasonably confident that I can use most of not all of the energy without exporting it.

You will note that i haven't factored in a solar iBoost, the gadget that feeds your extra electricity into an immersion heater? This saves you the effective cost of gas (10p/kWh) against the FIT (5p/kWh) and so does not make sense given that the device costs around £500.

Anyway, I've booked the installation for February and I will know in around a year how accurate my forecasts are!

I'm confident it will pay back in 7 or so year, possibly less, but more importantly will result in around 6,000 kWh of our electricity use coming from our own solar rather than from the grid where around 30% is neither renewable or nuclear.

An alternative way to look at it is to think of it as replacing ICE petrol miles with solar EV miles, that makes even more sense, environmentally.



Ultimately though the problem needs to be solved at a national scale, and the issue of the timing of supply and demand will need multiple sources, including wind, solar, much more nuclear and a lot more storage including pumped hydro and gravitational potential energy storage if we are ever to get below 20% gas in our energy mix. By then I hope that my solar system will have paid for itself many times over!

Edited by anonymous-user on Sunday 30th October 14:19

[DonkeyApple]

I'm yet to be convinced that home generation is either environmental or cost effective. From all the numbers I've ever run, including current high energy costs, I'm just not seeing valid arguments that make it worth spending the money. And as money is becoming more valuable this works further against the business cases.

The Grid is becoming greener and greener and will always be the most efficient and cheapest means to obtain electricity.

If the God and the utilities' argument is that our homes having PV on the roof will help them be more efficient, or batteries in our homes then they need to be paying anyway, not us!!!

Ultimately, all self generation seems to be is a great way to buy £10k worth of kit, hope to get your £10k back within 10 years and then sling everything in the bin as it's clapped out by then. And this all comes with the prime benefit of being able to generate electricity when you don't need it and not being able to generate when you do.

I can see a case for storage once batteries cease being too expensive but generally I remain of the opinion that £10k invested in dividend paying utilities will deliver a far superior return while producing far less pollution and buying from the professional energy generators will always be greener and cheaper than trying to make it oneself.

[anonymous-user]

AW10 said:

Evoluzione said:

You're forgetting that it's not only the private houses which make an excess in Summer, but all the solar farms do aswell.
If we carry on as per your plan we'll end up with far too much in Summer.
The answer is to make more in Winter, either by covering the whole country with solar panels or creating more with wind and water.

I wonder how much solar power we would need to power the whole country in Winter?
Or taking the above into account, how much investment is needed to go totally renewable in Winter?

Before TSHTF in Ukraine Germany had so much excess solar and wind generated electricity on some summer days that the wholesale price of electricity went negative during the day. No idea if that was still the case this past summer.

I think diversity of supply is the answer. Solar, hydro, wind, possibly wave, nuclear and the burning of something or another. PV solar generation in the winter is v low. And can't help but wonder if some degree of fossil fuel based generation will be part of the long term answer as a flexible and cost effective way of smoothing out the peaks and troughs.

At a National level solar makes less sense than hydro, wind, nuclear but for domestic use you can't really put a turbine on your roof, and anyway the wind patterns in urban areas are very convoluted and generally unsuitable.

Domestic nuclear never took off for some reason...

https://youtu.be/gi0oi-u3OxU

[anonymous-user]

DonkeyApple said:

I'm yet to be convinced that home generation is either environmental or cost effective. From all the numbers I've ever run, including current high energy costs, I'm just not seeing valid arguments that make it worth spending the money. And as money is becoming more valuable this works further against the business cases.

The Grid is becoming greener and greener and will always be the most efficient and cheapest means to obtain electricity.

If the God and the utilities' argument is that our homes having PV on the roof will help them be more efficient, or batteries in our homes then they need to be paying anyway, not us!!!

Ultimately, all self generation seems to be is a great way to buy £10k worth of kit, hope to get your £10k back within 10 years and then sling everything in the bin as it's clapped out by then. And this all comes with the prime benefit of being able to generate electricity when you don't need it and not being able to generate when you do.

I can see a case for storage once batteries cease being too expensive but generally I remain of the opinion that £10k invested in dividend paying utilities will deliver a far superior return while producing far less pollution and buying from the professional energy generators will always be greener and cheaper than trying to make it oneself.

Yes, of course you are right at a commercial scale, wind produces around 4.6g of CO2/kWh vs 70 g for solar, but until the national grid is largely renewable, there is a case for local renewable energy which has to be solar really (unless you live on farm). In addition it makes sense financially at the moment if you have the 'spare' capital and are already invested to your comfort limit (as we are) in other asset classes (because everything ultimately is an asset with costs, risks and returns.)

Anyway I'm happy ti take the plunge and will report back in around a year!

[dmsims]

Tobermory said:

(It's 2.6 m/kWh btw).

I didn't realise they started making EV tanks

[anonymous-user]

dmsims said:

Tobermory said:

(It's 2.6 m/kWh btw).

I didn't realise they started making EV tanks

They do, but they’re quite fast tanks. This is Pistonheads remember?

[dmsims]

But you said:

Tobermory said:

Absolutely, I should have said that my main reason for doing this is to be more environmentally friendly.

Tobermory said:

dmsims said:

Tobermory said:

(It's 2.6 m/kWh btw).

I didn't realise they started making EV tanks

They do, but they’re quite fast tanks

[anonymous-user]

dmsims said:

But you said:

Tobermory said:

Absolutely, I should have said that my main reason for doing this is to be more environmentally friendly.

Tobermory said:

dmsims said:

Tobermory said:

(It's 2.6 m/kWh btw).

I didn't realise they started making EV tanks

They do, but they’re quite fast tanks

Even at 2.6m/kWh, if you assume that solar 'emits' 70g of CO2 per kWh (from the manufacture of the panels etc amortised over their expected lifespan) that's 27g CO2/mile, about a 1/5th of the emissions of the smallest engined Golf, so not bad for a big comfy and fast SUV. Charging from the Grid won't be that much worse than that either.

As I said PH, man maths comes into play when it comes to cars. Even 2.6m/kWh is (much) greener than what I currently drive

Edited by anonymous-user on Sunday 30th October 18:34

[EW109]

DonkeyApple said:

I'm yet to be convinced that home generation is either environmental or cost effective. From all the numbers I've ever run, including current high energy costs, I'm just not seeing valid arguments that make it worth spending the money. And as money is becoming more valuable this works further against the business cases.

The Grid is becoming greener and greener and will always be the most efficient and cheapest means to obtain electricity.

If the God and the utilities' argument is that our homes having PV on the roof will help them be more efficient, or batteries in our homes then they need to be paying anyway, not us!!!

Ultimately, all self generation seems to be is a great way to buy £10k worth of kit, hope to get your £10k back within 10 years and then sling everything in the bin as it's clapped out by then. And this all comes with the prime benefit of being able to generate electricity when you don't need it and not being able to generate when you do.

I can see a case for storage once batteries cease being too expensive but generally I remain of the opinion that £10k invested in dividend paying utilities will deliver a far superior return while producing far less pollution and buying from the professional energy generators will always be greener and cheaper than trying to make it oneself.

I have spent quite a long time looking at the numbers and cannot see how it stacks up as an investment. If you have the cash, you get a better ROI doing something else with it.

[OutInTheShed]

Tobermory said:

....


At a National level solar makes less sense than hydro, wind, nuclear but for domestic use you can't really put a turbine on your roof, and anyway the wind patterns in urban areas are very convoluted and generally unsuitable.

Domestic nuclear never took off for some reason...
...

does hydro 'make sense' in terms of where to invest now?
I suspect not, the vast majority of good sites have been used already and we're left with a lot of tupenny ha'penny schemes which absorb a lot of effort writing reports and make it look like people are 'doing something' but don't offer even a remote hope of filling a useful % of needs.

If that effort went into wind or nuclear, we'd make more progress.

[MaxFromage]

DonkeyApple said:

Ultimately, all self generation seems to be is a great way to buy £10k worth of kit, hope to get your £10k back within 10 years and then sling everything in the bin as it's clapped out by then. And this all comes with the prime benefit of being able to generate electricity when you don't need it and not being able to generate when you do.

As I said earlier, with interest rates reverting to historical norms, the case against has strengthened, but the kit has been around long enough now to know that performance will far exceed 10 years. You are always at the mercy of companies staying in business, but many panels are warranted for 15 years plus, with performance warranties for 25 years with 85% efficiency guaranteed. Solar setups really are quite simple- some panels, cabling and an inverter. Inverters are consumables at around 10 years, but are fairly cheap.

Edited to say that the point does remain that many really don't understand they are more likely to be generating energy when they don't need it and vice-versa. That's why they work so well for commercial setups.

Edited by MaxFromage on Sunday 30th October 18:31

[anonymous-user]

MaxFromage said:

DonkeyApple said:

Ultimately, all self generation seems to be is a great way to buy £10k worth of kit, hope to get your £10k back within 10 years and then sling everything in the bin as it's clapped out by then. And this all comes with the prime benefit of being able to generate electricity when you don't need it and not being able to generate when you do.

As I said earlier, with interest rates reverting to historical norms, the case against has strengthened, but the kit has been around long enough now to know that performance will far exceed 10 years. You are always at the mercy of companies staying in business, but many panels are warranted for 15 years plus, with performance warranties for 25 years with 85% efficiency guaranteed. Solar setups really are quite simple- some panels, cabling and an inverter. Inverters are consumables at around 10 years, but are fairly cheap.

Exactly. I don't view it as an alternative to other forms of investing, of course do those first, but it's an additional stream whose primary motivation is to reduce your individual carbon footprint.

[DonkeyApple]

Tobermory said:

Exactly. I don't view it as an alternative to other forms of investing, of course do those first, but it's an additional stream whose primary motivation is to reduce your individual carbon footprint.

I get your point re being fully invested in all normal areas. Got the pension over the lifetime limit, a larger isa pot than you'll ever need, cleared the mortgage, finished paying school fees and all the important stuff then chucking £10-20k at something like this begins to fall into the 'fun' investment category. It's still an odd one as an investment as the capital is pretty much all gone on day one and the next decade is about just getting the capital back before you begin getting a positive yield and even then that yield is extremely low and then you're into the realms of maintenance, renewal and disposal costs that could put you back to square one.

But I'm not seeing how it reduces one's carbon footprint? The problem being that you've just created a whole load of carbon from buying the stuff, shipping it, transporting it locally and installing it and then you e got all the end of life costs of disposal. While running against you is the Grid itself which is becoming ever more renewable.

By some metrics, is it not plausible to put forward a case that it's all eco vandalism?

A million homes buying 16 million small PV panels, maybe a million Li batteries, a million control panels. All the associated factory pollution, the global shipping, the local road transport etc? And then it's all going to end up in landfill within our lifetimes?

I'm just not yet sold on either the financial or the environmental argument yet.

[anonymous-user]

DonkeyApple said:

Tobermory said:

Exactly. I don't view it as an alternative to other forms of investing, of course do those first, but it's an additional stream whose primary motivation is to reduce your individual carbon footprint.

I get your point re being fully invested in all normal areas. Got the pension over the lifetime limit, a larger isa pot than you'll ever need, cleared the mortgage, finished paying school fees and all the important stuff then chucking £10-20k at something like this begins to fall into the 'fun' investment category. It's still an odd one as an investment as the capital is pretty much all gone on day one and the next decade is about just getting the capital back before you begin getting a positive yield and even then that yield is extremely low and then you're into the realms of maintenance, renewal and disposal costs that could put you back to square one.

But I'm not seeing how it reduces one's carbon footprint? The problem being that you've just created a whole load of carbon from buying the stuff, shipping it, transporting it locally and installing it and then you e got all the end of life costs of disposal. While running against you is the Grid itself which is becoming ever more renewable.

By some metrics, is it not plausible to put forward a case that it's all eco vandalism?

A million homes buying 16 million small PV panels, maybe a million Li batteries, a million control panels. All the associated factory pollution, the global shipping, the local road transport etc? And then it's all going to end up in landfill within our lifetimes?

I'm just not yet sold on either the financial or the environmental argument yet.

I'm not so sure that local solar is so much worse than commercial as the equipment is pretty similar (the efficiency of the panels is similar) and commercial solar has to be manufactured and shipped etc.

For sure local solar is much worse than commercial wind or nuclear, no question.

Yes, I do see your point. If we get to a stage where the grid is as renewable as it can be then yes there would be no benefit in local solar and it could be potentially harmful. I'm just not sure we are anywhere close to that yet (the current UK grid mix produces around 200g CO2 per kWh of electricity) and so there is a window to make it work, and for sure there is a geeky fun element in it too.

For the record if there was a scheme whereby you could invest in additional commercial wind power or nuclear and get a 'dividend' similar to these savings then that would be a much better arrangement, but I'm not sure this exists.

Edited by anonymous-user on Sunday 30th October 22:48

[Biggus thingus]

Just taken the plunge and had a 14no panel(4.2 Kw) system fitted either side of east/west facing detached garage

Invertor and 5.2 KwH battery also in garage

All done and dusted for £8 and half K

App to monitor gubbins only works on Apple so Mrs Thingus is looking after that side of things but we're generating, despite shocking weather since it was installed on wednesday

[Previous]

Biggus thingus said:

Just taken the plunge and had a 14no panel(4.2 Kw) system fitted either side of east/west facing detached garage

Invertor and 5.2 KwH battery also in garage

All done and dusted for £8 and half K

App to monitor gubbins only works on Apple so Mrs Thingus is looking after that side of things but we're generating, despite shocking weather since it was installed on wednesday

That sounds good. Which part of the country are you in?