Plug in solar - best tarrif

Newbie_John

Let's keep this as more of a theoretical topic for plug ins without battery storage. Basic assumptions - 800W-1000W set, with 4 years payback.

What's the best electricity tarrif and approach you can think of to make the payback quicker?

1. E7 tarrif to get the night rate lower - make most of it on cloudy days, run any heavy items using 800W+ etc.
2. EON Smart Saver and position your panels West to cover most of 16-19 expensive period and enjoy cheaper hours throughout the rest of the day - with a extra cheap slot 2-5am.

As there's less sun in winter and especially none after 4 pm this may be just a solution for March - Ocotber.

I dont think Agile could work as it follows simple rules already - a lot of sun - a lot of renewables - low prices.. so not much gain with plug in.

sheenas

You could have 2 panel pointing west and 2’south. The washing machine and dishwasher can run over night. The solar is not going to help 4pm to 7pm in the winter.

I have a battery for 4pm to 7pm on the e-on tariff. Solar during the day covering the base load .

Its working well with this setup

QrizB

Some initial thoughts.

A plug-in solar PV system is unlikely to generate more than 1000kWh/yr and most will produce less than that. The best export tariff is Ecotricity's 16p/kWh so at most you're looking at earning £160 a year from export.

In practice, then, it's probably better to choose the best import tariff (where choosing poorly might cost you £160 a year or more) and then take your supplier's export tariff. If the supplier offers a pittance you could instead look at the 6p/kWh export tariffs from EON Next or Scottish Power that don't need you to be an import customer.

https://www.moneysavingexpert.com/utilities/best-solar-rates-seg-tariffs/

Newbie_John

@sheenas, Which EON tarrif?

Newbie_John

@QrizB , yeah mostly interested in import ToU tarrifs here.

There are so many variants with different hours E7, Heat Pump, Smart Saver.. with various hours, various rates - but to get cheaper rate at any given time you must accept higher elsehwere.

And as currently plug ins dont get paid for export, not worth considering.

tfhnota

Octopus are paying for plug-in export but you have to buy their approved kit (extra £200 to add to the payback period) and be a customer - they pay 16p between 4-7pm and less the rest of the time. Fuse have said they will be paying but no details yet and you will need to be with them to get export mpan. As an ultra low user I would be getting quite a bit going out for export except in winter when I do use electric spot heating to keep gas bill down. Import tariffs, probably just go for the lowest rate you can get away with unless ultra low user when the low s/c option is probably going to work best. A usable plug-in system is circa £500 for two panel but a 5kwh battery starts at £500 (48V, 100ah) plus inverter and charger, gets you to £650 total but would only work if you could get your heavy loads on an off-grid circuit, otherwise double or triple it to get it wired in properly.

If plug-in prices hit sub £400 for two panel then I would probably go for it and maybe add a battery later, or plug-in battery if they become legal, probably 2028, though. Plug-in battery with solar is the one that is going to open up the tariffs and really slash those bills.

Newbie_John

I do think export is not worth a hassle - you'll get £50 extra a year on equipment thats £400 more expensive.

But with the right ToU tariff you can save way more, even get you payback within a year just by pairing it well.

Switching to E7/Smart Saver - you can get up to 50% discount to your electriicty bill yearly.

Another option is for low users to pick the low standing charge - possibly it could work.

Qyburn

I don't see how 800W of plug-in solar is going to make any difference to whether a household can benefit from a TOU tariff.

debitcardmayhem

https://forums.moneysavingexpert.com/discussion/comment/82142875#Comment_82142875

What aboout EV or storage heaters?

Scot_39

For low users - if SEG can be had on kit at similar pricing - then it could be a deal breaker - to shorten pay back.

Even if only 20-25p a day in summer - less in winter - SEG export could perhaps hit £50. (exporting half rated 4-7pm at 16p alone - for 6m of the year - fag packet calc = £35 - plus more at the lower rate for other daytime hours)

For low daytime users - that could easily double savings.

Ive decided for me its a non starter - my back garden is shaded part of the day for ground mount - 6 foot fencing and then house itself from midday. The kits cannot be placed at bottom of garden without extensions or running the new socket their (with cost implications) and would ideally reinforce shed to roof mount to avoid shading issues - if height legal - again £100s extra for simple posts and framework.

I can see how TOU could help some folk - but thought more on lines of even a modest battery rather than solar - as a tariff like Next Saver could be a game changer - for those unable to avoid 4-7pm loads - even if only rated for shifting a few kWh - from 3 hrs super off peak 2-5am - to super peak 4-7pm window. But that would currently be a proper wired in solution as well.

But with E7 - I'd worry about the 17 hrs of day peak rates (at least next saver is lower than SR 18hrs/day on example chart - rather than say more like 7p min more expensive - worse on an aggressive balance a la UW sub 10p days. But thats without crunching numbers that carefully - just on face of it a safer bet for some - always with the normal 4-7pm caveat)

But if systems are going to be £400 more for SEG approval - is that Octopus specific kit - or kit vs DIY approach in general ?

But as above - suspect non trivial in terms of pay back if other SEG suppliers less restrictive - especially for low daytime users.

Qyburn

https://forums.moneysavingexpert.com/discussion/comment/82142929#Comment_82142929

Exactly, in those cases a TOU tariff makes sense, whether or not you have plug-in solar.