Plug in solar

Qyburn

So still excluding batteries.

Does G.98 inherently permit only one device? I mean not allowing the 3.6kW to be made up from multiple devices.

TroubledTarts

Just an update since I plugged my system in on 5th May.

This is actually quite conservative as most of our use of the microinverter is from battery during the Agile expensive hoursnwhich average more than the 25p kWh I have set in the ecoflow app.

Our system cost £260 so £197 to go til it's paid for itself.

QrizB

That's quite impressive!

I've generated roughly twice as much (not a huge surprise as I've got 1.8kWp of panels) bit I'm only valuing my kWh at 12p (as most get exported) so I'm also looking at £63-64 of earnings.

My system unfortunately cost me about £1300, once you add in the costs of cables, connectors, brackets and so on, so it's going to take a bit longer to pay for itself 😭

Before anyone goes reading anything into that, I'm not really the target market for plug-in /balcony solar - my electricity use is mostly covered by my professionally-installed panels for 6-8 months of the year. The plug-in system is just an experimental addition.

If I was a more normal household, I'd be looking at maybe £100-120 of earnings so far, £200-£250 for a full year and a 5-7 year payback period.

lohr500

Pretty similar to our system which went live on the 30th April :

Difficult to say what the actual savings have been so far, as the generation has replaced power drawn from the battery or topped up the battery. But on a few days we would have slightly exceeded the battery capacity without having the solar.

The battery charges up overnight at 5.48p per kWh..Worst case and assuming no losses from the charge/discharge cycle on the battery, we have saved 264 x £0.055 = £14.52.

Not a massive payback on the £350 cost to build the system. And we have been in the middle of summer with lots of very sunny days. With some allowance for the battery inefficiency and dipping into peak rate on a handful of days, then I guess we could be closer to £18 or £20 saving to date.,

However, with a longer term hat on, I suspect the EDF 5.48p off peak rate won't last forever, so the extra input from the solar will be worth more than it is today. And unless the panels or inverter fail prematurely, the system should keep generating for many years.

Qyburn

https://forums.moneysavingexpert.com/discussion/comment/82073644#Comment_82073644

However, with a longer term hat on, I suspect the EDF 5.48p off peak rate

What tariff is that by the way, and is it only available if you have an EV?

QrizB

What tariff is that by the way, and is it only available if you have an EV?

I'm not lohr500 but I know the answer to this - I hope they don't mind me answering!

Per this post, lohr500 switched to EDF's GoElectric EV tariff back at the end of March (but didn't need to have an EV).

That was before the US-Iran war, and energy prices have risen since then. EDF are quoting me 6.99p offpeak (7 hrs), 30p peak, 52.85p/day SC. On the face of it that's cheaper than my current Intelligent Octopus Go fix (8p offpeak, 32.72p peak, 47.71p/day SC) but the difference is only £20 a year or so.

lohr500

https://forums.moneysavingexpert.com/discussion/comment/82073770#Comment_82073770

It's EDF's GoElectric tariff.

I switched to EDF at the end of March this year when UW hiked their off-peak Eco7 tariff significantly in our region.

At the time, EDF were offering a fix to 01/11/27 at 5.48p for 7 hours off-peak and 32.31 peak, with a 58.21p s/c.
With all the uncertainty in the world, for me it was a no brainer to get a fix at those rates until November next year.

In early April I think it moved to 7p off-peak.

The peak rate cost really doesn't matter to us, as our battery is covering the daily peak period demand pretty much 100% of the time. Getting the lowest off-peak rate is the important thing for us as the electric AGA uses a shed load of off-peak power each night to reheat the core.

It is an EV tariff, but when I spoke to one of their customer service agents on the phone and asked if an EV was mandatory, he said not!! When signing up it talks about an EV being a requirement, but I can't see anything in the specific EV T&Cs that insist on this. All being well, we will be picking up our first EV at the start of next month, so it will be academic anyway.

Qyburn

So initially we'll be allowed one plugin system per household, but eventually should be allowed multiple systems, one per circuit!

I just totted up that we have eight socket circuits. There will be at least two more once I run a proper supply into my new shed. Conversely I'll bet many people don't even know, let alone know which sockets are on different circuits.

Reed_Richards

EDF are quoting me 6.99p offpeak (7 hrs), 30p peak, 52.85p/day SC. On the face of it that's cheaper than my current Intelligent Octopus Go fix (8p offpeak, 32.72p peak, 47.71p/day SC) but the difference is only £20 a year or so.

@QrizB I'm curious as to how you worked that out, given that EDF offer 7 hours off peak and Octopus offer only 5 hours. Because I charge my EV slowly then extra hours are valuable. And because I heat electrically I would like to achieve a temperature peak as late in the morning as possible. And because I have a home battery, the shorter the time the battery has to discharge before I get significant solar generation, the better. So if I were restricted to 5 hours then 02:00 to 07:00 would be a good deal better than 00:30 to 05:30, the cheap-rate time for the Octopus tariff.

QrizB

@Reed_Richards wrote:

I'm curious as to how you worked that out

I'm in a relatively unusual position, even for MSEers, with EV, solar and a 16kWh battery that will generally get us through the 18 peak hours even in the depths of winter (although when Mrs QrizB runs her convection heater in her crafting shed in Decemver or January, we do run out by late afternoon).

Our net import (house and EV) is around 3500kWh a year. Almost all of that is at the 8p off-peak rate, such that our composite rate is under 10p/kWh.

I estimate that switching to EDF might save 1p/kWh on that composite rate. Saving 1p/kWh on 3500kWh is an annual saving of £35.

But EDF's standing charge is 5p/day higher, an extra £18 a year. 35-18= £17 a year saved.

Octopus offer only 5 hours.

Intelligent Octopus Go gives me six hours, 2330-0530.

Because I charge my EV slowly then extra hours are valuable.

All EV charging is (currently) at the 8p rate on IOG, even when that's outside the 6 core off-peak hours.

because I heat electrically I would like to achieve a temperature peak as late in the morning as possible.

I heat with mains gas, when gas is cheap enough, so that's not a challenge I have.

And because I have a home battery, the shorter the time the battery has to discharge before I get significant solar generation, the better.

As above, in my case (large battery, gas heat) I don't generally need sunshine to get through the day.