4kw Solar panel quote

hairy_lairy

I have had a quote for 14 x 270 watt panels, a 3.6 dual MPPT inverter, installation, all MCS paperwork etc for a new build property at a cost of just over £4000. My main query is whether the savings sound right. Year 1 estimate for Annual PV generation is 3366 kWh. The FIT estimate is £134.62, Export tariff is £88.19 and the saving on electricity estimated at £329.87 (based on 70% usage). Total income year 1 total of £552.00.
What do you think?

pinnks

The price looks quite good for a first quote, as does generation, though that will depend on roof orientation, shading (or lack of it) and so on. Others will chip in on that.

I am not sure what FiT rates are doing for new installs but it is pure mathematics based on expected generation. I would assume the installer has provided the current rates, so should be correct based on the 3660kWh estimate.

What bothers me is the own consumption. I divert PV to hot water and to underfloor heating which increases my own consumption considerably and am now well-versed in living in series, not parallel when it comes to using high wattage items (coffee machine followed by kettle followed by toaster etc etc rather than all on at the same time) and to using washing machine etc on good days if possible when generating peak amounts.

Even so I only just squeeze in at 65% to 70% own consumption. Take out the diverted PV and I am down at about 40%. I would think that as an ordinary user who is out at work and so on you may save about £120 per year but again, others may give you some more accurate estimates but at 15p per unit they are suggesting you will save over 2,000 kWh through own consumption - that is about 60% of my total consumption!

I would get a couple more quotes to help you compare.

Best of luck.

silverwhistle

I'd second that regarding own consumption. I divert PV to hot water (only one occupant) but only have a little manually controlled hot air blower which takes the chill off in the lounge occasionally during the shoulder months.


You might save a nominal bit on less regular gas boiler servicing as I hardly use mine (a wood burner helps!), and not at all for domestic hot water between late March and early October.


Added to say that if you were to get an EV that might change the own usage significantly.


A little bit of peace of mind over fuel bills might be factored in too. Payment for mine came out of my emergency fund in a Cash Isa yielding 0.5%!

Martyn1981

I'll second and third the comments. The FiT and export figures look accurate, but for leccy savings, perhaps £120 (£80-£160) might be a fairer guess to start at. Perhaps 30% consumption of PV and 70% export.

If you are high leccy consumers, and can make use of daytime generation, then you could save more.

Great price for the system though, very impressive. When you say new build, do you mean the system will be installed during the construction, so saves on scaffolding etc? Just interesting to have these facts and figures in my head for other discussions.

hairy_lairy

Thankyou for informative replies both.
I should add that we're planning on having a ground source heat pump as well, with underfloor heating.
So I think I've realised that the electric savings could well be fairly high due to using the pump.
I'm also a bit concerned about the FITs scheme finishing April 2019, if we haven't got the build finished by then. Anyone know anything on this?
Be very grateful.

Merlin139

Might be wrong but before you can FIT for PV you need the final EPC for the building. You also need the MPAN of your import meter. The EPC cannot include the PV or you will not get the FIT.