Help on Solar Panels Quote

powerful_Rogue

Great review @ecraig , thank you.

I've got them coming out on the 25th to do an installation.

ecraig

That's really soon indeed. Hoping for a clear and cloud free day for you.
Today was an ok day for solar production. Washing machine was on 3 times, plus oven, dishwasher and shower. We have 73% battery left right now. It's being hammered today. 
Maybe I wish I had two batteries..... 

Planeteer

@love.sale my house seems to have the same orientation as yours, but with trees on one side. I presume you distributed your panels equally on both sides? And did you maximise your panels for the roof space?

@ecraig which gable did you put those batteries at? I have N and S and wondering where the gable is best put at (eg if N side is better for keeping it cooler, or some warmth on the S side will be better).

ecraig

Planeteer said:

@ecraig which gable did you put those batteries at? I have N and S and wondering where the gable is best put at (eg if N side is better for keeping it cooler, or some warmth on the S side will be better).

North.

No idea if it was due to keeping it cooler, or because the distance from the loft hatch to the north gable is two steps less.
If you don't already have a decent walk way to that area, I'd recommend fitting some loft legs and putting down some loft boards. 
We live in a 2 year old house so our loft was just full of insulation to start with. But the fitters really appreciated having a safe passage to the area. And when at one point there were 4 people up there I was pleased they had somewhere safe to walk.
Plus I think it's a building regulation to have easy walking access to the zone... 

shibli

I too also purchased the same system  from Light Renewables. My roof is East West so they will recommend to have solar on both sides. I would try and get as much panels as you can get, they seem to be hung up on 4kw but I would get more particularly if you have east west facing or a tree. As for the iboost I am not 100% convinced , it only worked for me in June and July as it simply will not generate enough hot water other times. If you going with an iboost I would look to get at least 5kw or more to make it worth while. 

IMO battery is worth while as right now I am using it to be charged over night at a low rate and then using it the following day. You will not get sufficient solar generation at this time of year so will be relying on the battery to make up any short fall. Over the summer months you will be able to charge the battery by solar.

Waywardmike

Maybe because my array is south facing but my iBoost has done me well from end of April to beginning of October.  We rarely had to top up with Gas.  It's only 180l though but plenty for our family of four.

From cold, it dumps about 4-5kWh into the tank.  I'm on deemed export, and had the iBoost before getting the battery.  If I was getting paid to export, I think that would be the better option as I doubt you'll make the money back on the iBoost from heating hot water alone.

Screwdriva

shibli said:

IMO battery is worth while as right now I am using it to be charged over night at a low rate and then using it the following day. You will not get sufficient solar generation at this time of year so will be relying on the battery to make up any short fall. Over the summer months you will be able to charge the battery by solar.

Depends on your usage pattern but many use cases will not recover the cost of a battery system with such high export tariffs.

Give this calculator a try with your actual usage/ purchase numbers. 

https://great-home.co.uk/solar-export-guarantee-seg-calculator/

shibli said:

As for the iboost I am not 100% convinced , it only worked for me in June and July as it simply will not generate enough hot water other times. If you going with an iboost I would look to get at least 5kw or more to make it worth while. 

An iBoost is still a sensible option for those who lack gas DHW heating i.e. using oil or grid electricity. It's also the environmentally right thing to do if you have the generation for it (4kWh or less won't be enough most months). Financially, just like battery storage, it no longer makes universal sense, given the high export tariffs.  

DougMLancs

I tried that calculator and adding a 9.5kW Givenergy battery for £3500 to a 4.4kW system (quoted £6k) only increased the payback time from 6.4 years to 8.2 years at current prices. I was surprised it was so close tbh. 

Alnat1

We had the solar/battery install done in March. We didn't go with an iBoost as we don't actually use that much hot water each day. We heat the tank with gas boiler for 40 mins in a morning and this is enough for 2 showers and a bit left, under 4kWh of gas, 40p a day. The price of installing the iBoost just wasn't worth it as a couple of Kw exported to the grid each day (Octopus Agile) covered the gas costs.

In fact, the extra 4kWh exported each day over 7 summer months, rather than being diverted to the tank, actually covered the DHW costs for the whole year.

An iBoost works well for people who get FIT payments but doesn't really add up with SEG. If gas prices go crazy high and SEG payments go down, we could always install one later.

Screwdriva

DougMLancs said:

I tried that calculator and adding a 9.5kW Givenergy battery for £3500 to a 4.4kW system (quoted £6k) only increased the payback time from 6.4 years to 8.2 years at current prices. I was surprised it was so close tbh. 

To be fair, that GiveEnergy battery is good value for money but isn't the point of spending thousands more, to actually reduce your payback time?