Should I get solar PV, or a renewable energy supplier?

PeelyPeel

I can't find an answer to this question from the angle that i'm asking it.

My goal is zero carbon energy usage (Or, as low as can be while I still use gas). My goal isn't a £0 electricity bill.

I'm considering solar PV + storage to help achieve this goal, but I will obviously still need a (renewable) electricity supplier. But then I thought, if my goal is renewable electricity, why even bother getting the PV panels?

The "point" of getting solar PV is to reduce your energy bill, and then in 10-15-20 years they pay themselves off, and then you are net positive. But, does this assume I will always have the same energy bill? Technology moves on. It's possible that in 15 years renewable energy is cheaper to buy (TBH I pray to all of Science that it's true, for the Climates sake)  than it is now, in which case my savings would be less and less, and the panels would technically take longer and longer to pay themselves off. At which point, their efficiency will be so "low" (in comparison to the efficiency of new panels/other sources will be 20 years from now), that they should just be scrapped (As we can also assume that my energy consumption will only increase).

In short, I trust all of the grid sized renewable and storage to be more efficient than my fix-in-time PV installation, so why would I even do it, I should just pay them and be renewable today with no £8000 outlay.

PeelyPeel

And another thought, if I leave it up to the grid, then on top of not paying £8000, I also don't need any modifications to my house, and nothing to maintain.

matelodave

There really is no way you can be 100% renewable unless you go off-grid. Whilst you are on grid, there's always the likelyhood that some fossil fuels may be need in the case of a failure of one of the renewable sources. I'd bet a lot of money that most "off-grid" zealots still have a back-up genny and are more than happy to light a fire when the leccy stops.

Doing what you can to save energy is probably a better way than spending silly amounts of money on an evolving technology that you may not actually benefit from if you move house before you get any payback.

I did explore getting solar when I got my heatpump ten year ago but there's nowhere I could install sufficient solar panels to provide my cold winter day energy consumption, especially on a day like today where its -3 outside, I cant see to the end of my garden and we've already churned through 48kwh since midnight and we've got another eight hours to go. The sun didn't shine yesterday or the day before so I'd need enough battery capacity to sustain me for the best part of a week at say 60kwh/day = 420kwh together with solar panels with sufficient generating capacity to both keep us going during the day as well as recharge the batteries within a sensible amount of time.

Just think of the size of a Tesla Power wall with about 400kwh capacity plus the number of solar panels you'd need to generate all the energy you'd need to power your home during the day and put all the energy back into the batteries that you've used the previous night. Chuck in your electric car and your really are stuffed.

Just my opinion

[Deleted User]

It’s a good feeling knowing that the panels on the roof have generated more electricity than the daily house consumption even though, in truth, what is actually consumed is a mix of Grid and Off Grid. I am not sure that I would get the same feeling just buying from a supplier that pays its wholesalers for Green Energy. I have no regrets paying out for PV solar knowing that these days it will take many years to break even. I accept that all electric homes pose a much greater challenge. 

Mister_G

Yes, my 3kWp array produced the princely amount of 1kWh today!

PeelyPeel

matelodave said:

Just my opinion

And thank you for it. To address a few of your points, i'm not a no-grid zealot, i'm just trying to minimise my negative impact on the world. Exactly like you say, "Doing what you can to save energy is probably a better way". My double glazing is over 10 years old (Maybe more), it needs replacing. Spending my "solar panel fund" money on that (And also going with a Renewable Energy electricity provider) will likely lower how much gas I use to heat my house, which would mean less C02. Maybe that's better overall, I don't know.

Dolor said:

It’s a good feeling knowing that...  I am not sure that I would get the same feeling  just buying from a supplier that pays its wholesalers for Green Energy.

I get your point, and this was my original thought process. But then I thought about what my goal was, and what the options were. I want to lower my carbon impact. I can do that with my electricity by just switching my energy supplier, and signalling to the industry by "voting with my money" that hey I the consumer want PV and storage on the grid please. I'm too late for the good  money making tariff, so the hope of paying it off in a reasonable amount of time and then re-investing that money in other energy efficiencies is something I can't count on.

Mister_G said:

Yes, my 3kWp array produced the princely amount of 1kWh today!

I don't know your energy usage, but 1kWh doesn't cover my house for a day, so I would have to switch my supplier to a renewable energy supplier anyway. At which point, why buy solar panels as my energy is already green. And, again, if I was on the old export tariff and could make a profit from the panels in a reasonable amount of time then it would be different (I would treat it like any other investment. Money in now, add time, more money out to invest in other things). But I don't think it will pay off in a reasonable amount of time, so I should seek better energy saving investments. 

Mister_G

PeelyPeel said:

Mister_G said:

Yes, my 3kWp array produced the princely amount of 1kWh today!

I don't know your energy usage, but 1kWh doesn't cover my house for a day, so I would have to switch my supplier to a renewable energy supplier anyway. At which point, why buy solar panels as my energy is already green. And, again, if I was on the old export tariff and could make a profit from the panels in a reasonable amount of time then it would be different (I would treat it like any other investment. Money in now, add time, more money out to invest in other things). But I don't think it will pay off in a reasonable amount of time, so I should seek better energy saving investments. 

We use an average of 20kWh per day, so the 1kWh I get on a dull winter's day just illustrates how little domestic solar contributes to my consumption.  My 3kWp array manages to produce about 3.3MWh in a year, a lot of which I can't use.  And yes, I'm fortunate to have had mine for 10 years, so get the full FIT.

I think that unless you have space for a large solar array and can afford the battery storage to go with it, then your proposal to try to use centrally generated renewable energy is the way to go.

Verdigris

Finding means of reducing consumption is the best first step. However, if you put the planet before cost you do need to account for the embedded carbon in whatever alterations you make. It is never simple but it is good that people are willing to try.

ASavvyBuyer

Changing to a "genuine" green energy provider could be a greener and more economical solution. It is also worth considering ways to reduce your use of gas/fossil fuel by getting an Air Source Heat Pump (ASHP) as they can be very efficient, providing you get a good quality make (not the cheap, noisy ones that some people base their opinion on).

Also, it may be worth considering Ripple Energy & Abundance to "invest" in renewable energy, but with the usual caveats of being aware of the risks of any investment.

Grumpy_chap

PeelyPeel said:

I would have to switch my supplier to a renewable energy supplier anyway. At which point, why buy solar panels as my energy is already green. 

What is a "renewable" energy supplier via the grid?  Especially as some of the companies are simply "virtual" generators and all of the domestic electricity supply retail companies are "virtual" distributors.  Whatever energy they generate is chucked into the one great big grid and whatever energy you use is sucked out of the one great big grid, complete with whatever inefficiencies and carbon load that comes with.  Are energy of the "renewable" energy suppliers really any more than a marketing gimmick?

The only way to be truly "green" is to go off grid, and account for the embedded carbon in doing so in a "pay-pack" approach.

The truly "green" solution is to focus on reducing your energy demand as the first step.

Verdigris

Are energy of the "renewable" energy suppliers really any more than a marketing gimmick?

Not if the amount of renewable electricity sold does not exceed the amount generated over a defined period. However, I'm not so convinced about so-called green gas. Depends on the integrity of the offset schemes and the amount of biogas included in the mix, as per electic.