anyone on here a solar expert?

the energy price increases forecast are making solar a lot more tempting.
my neighbour has just had 16 panels and a battery fitted for £11k.

I'm very tempted as the price increases mean the payback period will significantly reduce

anyone else tempted?

I had 29 panels installed in september 2021, I now already recovered 12% of the investment, I expect 20% this year.
So with 5 years payback and a guaranteed 90% production for 25 years (LG), I am bound to make a 400% return.

We also changed from diesel ( D5 ) to the FFRR P400e, the BMW tourer to an MX-30 and a diesel tractor to a battery powered zero-turn mower, and all electric tools. We still dropped the bill with 50% besides all these new EV-devices and 2 recently installed aircons..

One advice: try to make it 'stand alone' . The standard converters only deliver power from the panels when they are 'synced' with the grid. So with an outage : no power from the panels ! That was a bit of a rude awakening for me, didn't know this.

So I am considering to buy another 12 panels, make these autonomous and supply a 'grid power' for the other systems, combined with 50kWh in battery storage to get through the night. I-pace First Edition Santorini & 2nd car Mazda MX-30 Advantage red/black
PHEV P400e Hybrid Autobiography Loire blue= SOLD
D5 SD4 HSE Lux Corris grey = SOLD
D3 TdV6 HSE Lux Vienna Green =SOLD
P300 F-Type 2018 Ultra Blue = SOLD
25t F-Pace 2020 Loire Blue = SOLD

I have a 13 panel system with a 3.6kwh inverter , no fit, no battery, so use it or lose it.
I'm in Portugal and lots of sunny days, its reduced our bulls by about 50% and it runs our pool pump and heater for free.
Net cost was 1500e after receiving a grant, it will have paid for itself after just over 2 years

I had 4kw installation with a battery Pack fitted 7 years ago at a cost of around £8k With the Feed in Tariff & taking into account the savings on taking power from the grid the break even point was around 5 years.

AFAIK (in the UK) you are limited to a 4kw installation without having a survey carried out by National Grid. It may have changed since our system was installed though.

We do try to run things like the dishwaher & washing machine when the sun is out, but we are not ruled by it like some people.

If you have the funds then go for it.

Don't forget to check your buildings insurance - some companies increase the premium, some won't cover at all.

DONT try to make it 'stand alone' you need it grid tied to supplement your energy input from the grid. Grid tied inverters normally have an output for emergency power cuts, I have a 13 amp socket on mine that allows me to run essential items. If it's not grid tied you need an inverter capable of supplying you maximum load, theyre relatively inefficient and expensive.

Battery storage is essential and if you can, get an off peak tariff like Octopus GO, charge the batteries up off peal i.e. 00:30 to 04:30, run from 04:30 to 09:00 or whenever your panels start to output. The battery also covers times when theres insufficient solar power to meet demand. As the day progresses the battery will recharge ready for evening time when again it supplies the power you need through to 00:30 when the off peak rate starts. Octopus GO off peak is currently 7.5p per kWh.
My system was installed 3 months ago, our old tariff we paid £178 per month, Octopus put that up to £465 per month with the price increase (our tariff came to an end). Our last 3 bills have been £68, £71 & £62 so you can see it's saving £££££££.
The whole system including 6.7 kW panels, 6kW Inverter, 7kWh battery, Energy diverter for Immersion heater and Zappi car charger came in a whisker under £11k. The way its all running and taking winter daylight reductions into account along with the October price rips, we should break even in around 3.5 years.
I am building additional power storage to run the heatpumps during winter, all of our electricity will then be at 7.5p or free. In 3 months we have only used 8 kWh of peak rate power. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

"Grid tied inverters normally have an output for emergency power cuts, I have a 13 amp socket on mine that allows me to run essential items."

The 'stand alone' is a capability, not a requirement !

From what you describe this is exactly what you have : grid tied with standalone ability..

So you did it right without knowing it.. .. send your engineer a crate of beer...


Running your heatpump in winter from storage; that is to charge off peak and use during peak hours ?

Most heatpumps you can program that, resulting the system in 'overheating' in preparation of "off"

when its peak rate ! Check you heatpump manual ( I have a Nibe groundsource that has this).

But this only works if you have underfloor heating. Alternatively you can place a larger storage

for the central heating. Works as a 'battery' but it is 6x cheaper to run and depreciate !

We don't have a peak rate. We feed back into the grid and deduct that from what we take out (metered). I-pace First Edition Santorini & 2nd car Mazda MX-30 Advantage red/black
PHEV P400e Hybrid Autobiography Loire blue= SOLD
D5 SD4 HSE Lux Corris grey = SOLD
D3 TdV6 HSE Lux Vienna Green =SOLD
P300 F-Type 2018 Ultra Blue = SOLD
25t F-Pace 2020 Loire Blue = SOLD

It sounded like you were talking about an off grid inverter rather than a grid tied one hence my comments. All grid tied inverters that i know of have an emergency output. It has to be done this way due to regulations, if engineers switch off the grid supply, the last thing they want is everyone's inverter back feeding, it would be shocking LOL

Our heatpumps are air to air heat pumps aka air conditioning units, we use them very economically in the winter for heating and the battery I'm building will be fine for that.

Feeding back into the grid isnt worthwhile here, 7.5p per kWh on some tariffs more normally 4.5p whereas buying the grid is around 35p average now. Store / use all you can generate is the best option. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

SamThomas wrote:

AFAIK (in the UK) you are limited to a 4kw installation without having a survey carried out by National Grid. It may have changed since our system was installed though.