New Solar PV Installation

JKenH

scorp_a said:

Anyone using SOFAR inverter? Not sure if this is better/worse than Solis.

When my panels were installed a couple of years ago I had 2 Sofar inverters. I had a lot of problems with tripping out first thing in the morning as the panels woke up. The installer replaced them with Solis and that cured the problem. I also found the Solis inverters woke up earlier than the Sofar.

As far as IBoost is concerned, mine has paid for itself in a couple of years but I don’t have gas and one of my two hot water tanks is heated solely by electricity and both are very well insulated. I think in calculating the saving on water heating costs you should, as others have suggested, base it on the cheapest alternative cost of heating water, not base it on daytime electricity rates unless you have no alternative. Also take into account the time you use the water. If your biggest demand is early morning you will need to take into account overnight losses (potentially 25%). If early evening use then your storage losses will be minimal.

Martyn1981

Coastalwatch said:

While I appreciate this website is a principally a money saving tool, accelerated global warming is clearly demonstrating it is a threat to the very existance of human life on this planet so making judgements based purely on economics and ignoring sustainability could be considered short sighted at best and maybe even reckless otherwise. Take your pick!

In case it assists the poster in coming to a decision on which system to adopt, I put some figures below of our journey to emission free energy consumption including the purchase of the largest pv array our roof would accommodate, 8.85 kW.

With full GCH, rads, hot water and gas hob in 2017, our first full year of occupancy, we consumed 8901kW of gas and with no pv, consumption of leccy was 2404kW so totalling 11305kWh's. Circa £906.

Since then we've installed a pv array, purchased an EV and gradually decommisioned all gas appliances. Apart from three months use of gas for cooking only, 2020 will be our first full year reliant purely on renewable leccy. Being three quarters of the way through we've so far imported 2402kWh's. There are three heavy months of import still to be added. If last years figures are anything to go by then these may amount to 1232 kWh's so making a possible total of 3634kW's of import. Circa £635 plus £64 for 3 months gas(incl 9 months S.C's)

So far 948 kWh's has been for space heating(2 x ashp's) and 304 for the EV or approx 50% of all that consumed to date.

PV generation typically 9500/yr so approx £260 received in export and approx £800/yr saved in not having to purchase the dreaded diesel!

The array covers all our domestic energy needs and approximately 75% of motoring mileage/year. Naturally import is unavoidable in winter when consumption is heaviest and generation weakest but hopefully the above figures give a flavour of what the future may hold given the opportunity.

We don't have iboost but certainly something to be considered as it's especially useful in the shoulder and winter months.

Really nice mate. I think it's so important to look at what is possible rather than focus on all the theoretical negatives, which tbh haven't changed in ten years on here. We can't compete with you, mainly because of less PV and E/W, but over the years our leccy import has fallen from ~4,000kWh to about 1,500kWh*, and gas from ~10,000kWh to about 6,000kWh*, and petrol from around 1,200lt to zero**. It's amazing what is possible, and how so much can revolve around domestic PV and a green tariff ...... plus some side investments in green energy to mop up the rest. With modern panels of say 370Wp, we could (DNO permitting) now be generating nearly 50% more, which would improve all the numbers. So best of luck to scorp_a and all the new PVers joining this mad ride.

*Leccy import now rising due to the ASHP (second finally on its way after C19 delay from Mch), and BEV charging. I expect it to hit around 3,500, or 4,000 if we use the new ASHP on E7.
Gas consumption will hopefully fall below 5,000 with the additional ASHP, and perhaps a bit less if the E7 idea works.
**We did buy petrol this year, two tank fulls and most of the second tankfill sold with the car.

Hexane

Coastalwatch said:

While I appreciate this website is a principally a money saving tool, accelerated global warming is clearly demonstrating it is a threat to the very existance of human life on this planet so making judgements based purely on economics and ignoring sustainability could be considered short sighted at best and maybe even reckless otherwise. 

That's fair enough, so long as installers providing quotes with an iBoost include a disclaimer for houses that also have gas central heating, saying "included in this quote is a device that is guaranteed to lose you money, it is included to avoid making judgements based purely on economics and ignoring sustainability."

The cost/savings/earnings breakdowns that I'm sure all installers still include, should also note that for every kWh "saved" by the iBoost, the household will be losing out on 5.5p (or whatever the going rate) that could have been earned by selling that kWh.

We don't have iboost but certainly something to be considered as it's especially useful in the shoulder and winter months.

Not the case for me, the similar device installed here is most useful in the summer and shoulder months, it's of very little use in winter.

scorp_a

Very useful comments. Thanks. 
I understand the cost impact of having iboost.  Just thought I would reduce use of gas if possible. Can always turn it off if it's really not worth it. Also grid may put limits in export sometime in future? 
Regarding my final setup. I decided on 8.3Kw PV (JA 460x18) , 7.5 kw sofar inverter. 
Comes around £6.5k  including iboost and bird guard. Hope DNO approve it. 

Coastalwatch

Wow! That sounds a great deal, you must be a tough negotiator. Reckon somebody should sign you up to assist with Brexit negotiations.

Will keep fingers crossed for you that the DNO play ball.

scorp_a

Coastalwatch said:

Wow! That sounds a great deal, you must be a tough negotiator. Reckon somebody should sign you up to assist with Brexit negotiations.

Will keep fingers crossed for you that the DNO play ball.

It's mainly due to the availability of higher rated panels for relatively cheaper price. 350w panel cost almost same money. 
Yes, let's hope for DNOs green flag. 

Solarchaser

Hexane said:

Coastalwatch said:

While I appreciate this website is a principally a money saving tool, accelerated global warming is clearly demonstrating it is a threat to the very existance of human life on this planet so making judgements based purely on economics and ignoring sustainability could be considered short sighted at best and maybe even reckless otherwise. 

That's fair enough, so long as installers providing quotes with an iBoost include a disclaimer for houses that also have gas central heating, saying "included in this quote is a device that is guaranteed to lose you money, it is included to avoid making judgements based purely on economics and ignoring sustainability."

The cost/savings/earnings breakdowns that I'm sure all installers still include, should also note that for every kWh "saved" by the iBoost, the household will be losing out on 5.5p (or whatever the going rate) that could have been earned by selling that kWh.

We don't have iboost but certainly something to be considered as it's especially useful in the shoulder and winter months.

Not the case for me, the similar device installed here is most useful in the summer and shoulder months, it's of very little use in winter.

I commend your moral crusade there, but you base your absolute statement on the assumption that all electricity providers will pay this 5.5p export , as far as I'm aware there are only a few power companies doing this?

scorp_a

Btw, I got quotes from eon, eec, ecocetra and forever-green. I am going with forever- green based in Cheltenham.

ASavvyBuyer

scorp_a said:

Btw, I got quotes from eon, eec, ecocetra and forever-green. I am going with forever- green based in Cheltenham.

Good choice, they installed our system for us and would happily use them again.

Petriix

Solarchaser said:

Hexane said:

Coastalwatch said:

While I appreciate this website is a principally a money saving tool, accelerated global warming is clearly demonstrating it is a threat to the very existance of human life on this planet so making judgements based purely on economics and ignoring sustainability could be considered short sighted at best and maybe even reckless otherwise. 

That's fair enough, so long as installers providing quotes with an iBoost include a disclaimer for houses that also have gas central heating, saying "included in this quote is a device that is guaranteed to lose you money, it is included to avoid making judgements based purely on economics and ignoring sustainability."

The cost/savings/earnings breakdowns that I'm sure all installers still include, should also note that for every kWh "saved" by the iBoost, the household will be losing out on 5.5p (or whatever the going rate) that could have been earned by selling that kWh.

We don't have iboost but certainly something to be considered as it's especially useful in the shoulder and winter months.

Not the case for me, the similar device installed here is most useful in the summer and shoulder months, it's of very little use in winter.

I commend your moral crusade there, but you base your absolute statement on the assumption that all electricity providers will pay this 5.5p export , as far as I'm aware there are only a few power companies doing this?

It would be quite a costly choice to go with a supplier paying significantly less than that 5.5p rate and hardly rational justification for wasting money on an uneconomical diverter.