What do I need for a full system.

Some thoughts:

1. Agreed
2. Battery storage is still not financially viable as the costs are still greater than from buying from the grid. Current rules allow reduced VAT if buying with a system - but a system could just be one extra panel with a micro inverter - you could possible leave room and capacity for this should costs decrease.
3. I looked at this and decided it wasn’t viable. The systems are very expensive and unlikely to pay for themselves. My current boiler should be about 24kW which if it were on full time for lets day 5 hours a day would use 120 kWh. Assuming a COP of around 4 - that means I neeed 30 kWh of electricity to run it. At this time of year I’m lucky to get between one and two kWh - so I get around 20-30 p of free electricity. It’s fair to assume running costs of the heat pump to be around the same as that of a gas boiler. So this 20-30p saving is about all there is to be had which will never pay back the investment of the pump.
4. I think is academic.

Hope this helps

Hi Martin, just to add a little to ET's lines I've added a link to the thread to which I believe he is referring below.
Having had Solar installed only this last April I'm all rather new to this as well. However if you follow the thread below you will see my contributions, mostly seeking advice, so have benefitted from the sound advice passed on by other members. ET is correct in that the thread was originally set up to utilise spare solar energy produced through spring, summer and autumn. Heating in spring, autumn then cooling in summer. With air to air heat pumps delivering around 4/5 kWh of heat for every single kWh of electricity consumed then the cost of heating, even when being drawn from the grid, is reduced to that paid for gas, or possibly even less. Naturally some of the time it will run purely by the solar panels.

As there name suggests I don't believe they can be used for heating water and therefore not able to feed your radiators. But if you are keen on reducing your dependency on FF,s then they are certainly worthy of consideration. Given the right circumstances they can be used to replace conventional radiator systems as we shall be trialing this winter.

We've had a single unit installed in the lounge of our bungalow as the thread originally suggested. This heats our lounge/diner and also the hall leading from it. If you follow the thread you will discover we are planning a second unit in our small lobby from which doors to the bathroom, two bedrooms and hall open from it. Given that bedrooms are not usually heated as much as other rooms we are hoping this second unit will make the bathroom toasty while supplying just sufficient heat to the bedrooms also. I may be being a little optimistic but am hoping the two units could make our existing gas powered CH system redundant.
As stated it may not suit every property but I believe is a cost effective(both in installation and running costs) means of replacing an existing heating system and well worth spending the time investigating to see if it would suit your home.

I'm sure others more experienced will add their thoughts/advice too.


https://forums.moneysavingexpert.com/showthread.php?t=4715287

Seems overpriced to me.

I had 17 x 300w, each with an optimser and a solar edge inverter across 4 different roofs, including a flat one, for £6200 back in September. I'd hope that prices will continue to fall.

The iBoost thing is about £300.
https://www.marlec.co.uk/product/solar-iboost/?v=79cba1185463

You said 14 x 300w, but then said 8 on the front, 4 on the back? Is it 12 or 14?

Is there anything stopping you having more panels (aside from cost?). Remember, this is a one off install and the FIT can only be applied for once against the first install. And no one ever said 'less solar is better'.

Installation company in sig; CTS Renewables. Yep, including VAT and everything.

As per details in this quote thread: https://forums.moneysavingexpert.com/showthread.php?t=5928038

You need no permission as long as you don't install greater than a 3.68kwh inverter. I have 5.1 of panels on a 3.68 intervter, no DNO permission required.

On a split aspect install, sticking with a 3.68 inverter can make sense as you are unlikely to get the full beans out of two lots of panels facing different directions at the same time.

The only time you need DNO permission (G59) is when you install an inverter greater than 3.68. So maybe you have 5.5kwh of panels facing the same way and a 5kwh inverter makes sense. The installer should be able to advise on this.

Depending on your region (and local power authority) there may be a charge for the application, so worth checking. Northern Power wanted £300 for my application. I didn't think i'd get that back in FIT over the long term, so went with the 3.68 inverter instead and saved the money. But your situation may be different, so i'd suggest getting Excel on the go and do some maths if required.

Hope this helps.