Not Another Solar Quote Thread

bigstevex

Alnat1 said:

I'm on Agile in and out as we don't have an EV. This summer the Outgoing prices were really high but I don't think that's going to be the norm. The prices overnight on Agile have had some cheaper slots recently and I've made use of these, topping the battery up and running appliances. Windy weather tends to mean lower prices on both incoming and outgoing.

It really depends if you want a "fit and forget" type system, or if you're like me, energy monitoring becomes a new hobby and you've time to check out the prices and make adjustments to when you run appliances, fill the battery etc.

E7 might work but I don't know the new rates.

I have a bit of OCD I think so I'm more than happy to be watching prices etc to a certain degree.  Will definitely do some more research

bigstevex

Alnat1 said:

My system was installed in March, Lux hybrid and pylontechs. I've got 5.25 on the roof and 4.8 batteries. I paid £8,600. Happy with the set up and more battery wouldn't make financial sense for me. 

As mentioned above, get more on the roof if you possibly can or consider saving a bit with less battery. Pylontechs are easy to add later, panels aren't.

I found this calculator which seems to make more sense of ROI than the installer quotes
https://great-home.co.uk/solar-export-guarantee-seg-calculator

Solarchaser said:

Looks a decent quote for decent kit, no need to pay over the odds for a brand name.
I have lux inverters as do a few regular users, no issues that i know of so far.

I would agree with Mr. Brass though, if your roof will physically take more panels, fill that blighter with panels., you can see yourself the panels are £180 a pop, so doubling them would only cost another £1800 for double the solar benefits 

So they came round yesterday and measured the roof exactly vs the approx one.  They've managed to fit 15 panels on there now.  The velux's we have were the tricky obstacle they said but all sorted.

Now £10.5K for 5.77KW JA Solar 385s and 7.2kwh Pylon techs fully installed/scaffolding/MCS etc.  My only concern which I've just challenged them on is why they have kept the inverter at 3.6Kw, makes no sense otherwise than to avoid the G99 application!

70sbudgie

It makes a bit more sense if it is a hybrid inverter as it will charge the batteries before converting to AC. You have almost 3.5 hours charging if your pv panels are at max output. I have EW panels, so am not totally sure on the likelihood of having max gen for more than 3.5 hours.

bigstevex

70sbudgie said:

It makes a bit more sense if it is a hybrid inverter as it will charge the batteries before converting to AC. You have almost 3.5 hours charging if your pv panels are at max output. I have EW panels, so am not totally sure on the likelihood of having max gen for more than 3.5 hours.

It is a hybrid inverter, have I missed something special about these?

bigstevex

So I just read that the Luxpowertek hybrid can do 6000W max solar input, the max export to grid is 3.6 and the rest can be used on charging batteries or running the house (i.e the other 2.1kw if it was giving max power from the panels).

Does that sound right?  I never realised that was a thing

Alnat1

I'm no expert but this is how my system works.

My Lux hybrid can be charging the batteries (DC) and then up to 3.6kw (AC) can be used in total for powering the load and with the excess going to the grid. 

I only have 2 x 2.4 batteries and the max I see them charging/discharging is 2.6kw. I have read that if I had 3+ 2.4 batteries they would charge/discharge up to 3.6kw (DC) Battery Storage - Energy Stats UK (energy-stats.uk) is where I found lots of great info.

bigstevex

Alnat1 said:

I'm no expert but this is how my system works.

My Lux hybrid can be charging the batteries (DC) and then up to 3.6kw (AC) can be used in total for powering the load and with the excess going to the grid. 

I only have 2 x 2.4 batteries and the max I see them charging/discharging is 2.6kw. I have read that if I had 3+ 2.4 batteries they would charge/discharge up to 3.6kw (DC) Battery Storage - Energy Stats UK (energy-stats.uk) is where I found lots of great info.

Ah ok, so once my 7.2kw battery is full anything over 3.6kw being generated will just be clipped.  How many hours of the day would a 5.77kw array generate over 3.6kw I guess is my next quesstion?

Alnat1

You can manually alter the settings early in the day on the Lux system, so the batteries won't fill (change the 100% fill rate to 0%) then change it back up later, as the system gets up towards 3.6kw. 

This helps with the capping but unfortunately with the Lux, there isn't a simple way to set it at certain times of day (fill batteries 11.30am - 15.30pm would be ideal) and you have to remember to manually change it online or by the app.

Manually filling batteries from the grid or discharging to the grid can be set by hours (great with TOU tariffs) but there's no time option for filling batteries from PV.

ABrass

bigstevex said:

Alnat1 said:

I'm no expert but this is how my system works.

My Lux hybrid can be charging the batteries (DC) and then up to 3.6kw (AC) can be used in total for powering the load and with the excess going to the grid. 

I only have 2 x 2.4 batteries and the max I see them charging/discharging is 2.6kw. I have read that if I had 3+ 2.4 batteries they would charge/discharge up to 3.6kw (DC) Battery Storage - Energy Stats UK (energy-stats.uk) is where I found lots of great info.

Ah ok, so once my 7.2kw battery is full anything over 3.6kw being generated will just be clipped.  How many hours of the day would a 5.77kw array generate over 3.6kw I guess is my next quesstion?

You should go back to them and ask for that with a 5kW inverter.

The worst of the clipping would only happen on days that you are generating far more power than you need. Effectively you can assume that any clipping will only affect SEG export, which means it is worth much less. I can't work out the numbers, I don't have good enough stuff to extrapolate from, but depending on how much extra the 1.77kW will cost you it might be worth it.

BTW inverters sometimes manage an extra 10% performance than their rated value.

bigstevex

ABrass said:

bigstevex said:

Alnat1 said:

I'm no expert but this is how my system works.

My Lux hybrid can be charging the batteries (DC) and then up to 3.6kw (AC) can be used in total for powering the load and with the excess going to the grid. 

I only have 2 x 2.4 batteries and the max I see them charging/discharging is 2.6kw. I have read that if I had 3+ 2.4 batteries they would charge/discharge up to 3.6kw (DC) Battery Storage - Energy Stats UK (energy-stats.uk) is where I found lots of great info.

Ah ok, so once my 7.2kw battery is full anything over 3.6kw being generated will just be clipped.  How many hours of the day would a 5.77kw array generate over 3.6kw I guess is my next quesstion?

You should go back to them and ask for that with a 5kW inverter.

The worst of the clipping would only happen on days that you are generating far more power than you need. Effectively you can assume that any clipping will only affect SEG export, which means it is worth much less. I can't work out the numbers, I don't have good enough stuff to extrapolate from, but depending on how much extra the 1.77kW will cost you it might be worth it.

BTW inverters sometimes manage an extra 10% performance than their rated value.

So we could be getting 4kw anyway really, seems like what Alnat1 says, I'll have to keep an eye on the app to charge batteries mid day instead of first thing.

I did ask this before to installer though, they've said it's ~£200 to change from the 3.6 inverter to the 5kw and because we're SP Energy network area it's now a minimum charge of ~£250 for them to even look at the G99 DNO application, that's before any additional costs SP Energy might apply.

They said I'm really on the boundary of whether or not to go G98/G99 an it's totally up to me.  They said they will happily go G99 for me, I just have to understand the extra potential costs and delays (min 8 weeks for an answer off SP Energy).

So to get a minimum extra £450 in SEG payments back could take some time (~3000Kw if octopus stays at 15p).