Had my Solar PV installed last week and couldn't be happier!

j2d · Post by **j2d** » 24 Oct 2011, 23:00

Had my Solar PV installed last week - and couldn't be happier with my choice

West facing roof in Essex

16 x 245W sunlink panels
Aurora one inverter
Energy monitor
Both with a 10 year guarantee

All for £9750!!!

The installation went like a dream, a team of 5 turned up at 8am (1 doing the electrics, the rest on the roof)
Real nice proffessional guys, very neat and tidy job, who were more than happy to do exactly what I wanted - even trimmed down my soil vents for me.

Swithched on 2:30ish and even on a West facing roof with a large oak tree giving plenty of shading (which is soon to be trimmed) it produced 6 units and peaked at 2.657Kw.

Paid the final payment over the phone, and recieved my MCS cert and invoice within half hour by email, which I sent off this morning

Got up the 1st day at 7:30 and it had already switched on, and was at 11:30am producing just over 2Kw's, put the washing machine and 1200 watts of electric underfloor heating on, and the meter outside wasn't moving!!! Happy days

I really couldnt recommend this company enough, they are a large nationwide company with lots of experience, great customer service and most importantly great price!!

Anyway, hopefully the pics below will work and you can see the install for yourself.

John

Not sure what the rules are on posting the companies details, so if anyone wants anymore info drop me a pm.

Post by **kenneal - lagger** » 25 Oct 2011, 03:40

Welcome j2d

We are generally happy to have posts from satisfied customers as long as you have no other connection to the company and are not getting paid in any way.

I wouldn't recommend electric underfloor heating to anyone though. Come to that I wouldn't recommend any form of electric heating to anyone: wrong use for an expensive commodity. I would recommend a wet underfloor heating system though as they are very efficient.

biffvernon · Post by **biffvernon** » 25 Oct 2011, 08:02

That was cheap! £2.50 per Watt.

emordnilap · Post by **emordnilap** » 25 Oct 2011, 10:41

Welcome j2d and well done, that sounds like a great company to engage.

Keep us posted on figures, problems, benefits, disadvantages etc.

Post by **adam2** » 25 Oct 2011, 12:22

Congratulations.
I would however agree that electric underfloor heating is very seldom a wise use of electricity.
Electricity is a relatively costly form of heating and seldom justified for regular use.
Exceptions include temporary, emergency or short term needs, or when the heating demand is very small.

Remember that your new system does not provide any backup or standby supply. It should be worthwhile on financial or enviromental grounds, but does not protect against blackouts.

j2d · Post by **j2d** » 25 Oct 2011, 21:31

Thanks for the comments.

Re the electric underfloor heating, we did look into the wet system and this was my 1st choice, but the concrete floor would have been a bitch to remove to make way for the pipes, ideal for new builds, but not when you already have a solid floor. So I decided to go electric, only to warm the stone tiles, not heat the room. 1.1kw system covers my kitchen, hall and downstairs loo, and is now free to run on those cold sunny winter days! and as its a natural stone floor, it holds the heat for quite a while

John

Post by **kenneal - lagger** » 26 Oct 2011, 02:55

It sounds like you have no insulation under the floor, John. That is an horrendous waste of energy and I would use the system as little as possible. A wet underfloor system is usually installed with a minimum of 50mm of insulation and usually more like 200mm nowadays. I agree that it wouldn't be possible to install that in a retrofit situation. If you don't have a high water table you can dig up around your house and install xps, extruded polystyrene, Styrofoam or similar, insulation up to 200 thickness against the wall. This perimeter insulation, although not as good as underfloor insulation, will help retain the heat.

I am writing this mainly for the benefit of anyone else looking at a similar installation.

emordnilap · Post by **emordnilap** » 26 Oct 2011, 10:45

j2d, I had concrete floors and yes, they always were a very bad idea. We took the plunge and removed them, re-laying a solid (reinforced) screed on top of insulation, then quarry tiles in one room - no underfloor heating at all - and suspended wooden floors with Warmcel insulation in others. The walls are stone, so when we light the stove, the heat seems to stay in the house for days!

Anyway, enough about us; enjoy your system and keep us up-to-date.

j2d · Post by **j2d** » 26 Oct 2011, 20:17

kenneal - lagger wrote:It sounds like you have no insulation under the floor, John. That is an horrendous waste of energy and I would use the system as little as possible.

I fitted a layer of compressed insulation specially designed to be used with electric underfloor heating, it wasnt cheap, but stops any of the heat going onto the screed and reduces the 'warm up' time by 60% and helps hold the heat in the stone.

John

Post by **kenneal - lagger** » 27 Oct 2011, 05:04

j2d wrote: but stops any of the heat going onto the screed

No insulation can stop all of the heat passing through it can only slow it down. The more an insulation material is compressed the less it insulates.

The only insulation material that would make a significant difference at under 25 mm is a vacuum insulated panel such as Nanopor. These need to be protected by a steel sheet as they lose the major part of their insulation properties if the foil covering is punctured.

j2d · Post by **j2d** » 28 Oct 2011, 18:33

Well i'm happy with it, and it seems to stop the floor getting cold in the winter even without the electric underfloor heating on.

Had it on today too, even on a completely overcast day, the solar was producing more than enough to power it and the dishwasher!

Happy days

John

Post by **kenneal - lagger** » 29 Oct 2011, 02:00

I'm sorry to keep harping on about this, John. Well I'm not really because I think it is an important point. The point of the FIT is to encourage people to invest in renewable energy to produce valuable electricity for essential uses such as powering machines and providing lighting.

I'm glad that the insulation you have keeps the floor warm even in winter without the electric underfloor heating on. That begs the question "Why put the electric underfloor heating on in the autumn if you don't need it in the winter?" Answer, "Because I can and it doesn't cost me anything." In reality you think it doesn't cost you anything but in fact it does. Waste costs us all and that is what you are doing.

Using the subsidised electricity produced on site to power heating is environmentally and morally wrong even if it is economically sensible. There is something fundamentally wrong with your house if you had to have the heating on on the warm autumn day that was today. My living room was at 21C with no heating on. Even if we hadn't had any sun the temperature would have been 18 or 19C. We haven't had any heating on since last weekend and we only put it on for the one day because we had visitors. Our house isn't that well insulated either although it does have phenomenal thermal mass.

I'll say it again, electricity shouldn't be used for heating as there are other things such as insulation, jumpers, the sun, coal, gas and wood which can take care of the, what should be in this day and age, very small amount of heating required for a house. Electricity should be reserved for high level uses such as powering machinery and providing electric lighting. I hope I'm not the only one who thinks this way.

(Goes away to stroke his environmentalist's beard and put on some thick socks to keep his sandal clad feet warm - I'm not joking)

An Inspector Calls · Post by **An Inspector Calls** » 29 Oct 2011, 09:44

I don't see the problem you're having with dumping PV generated electricity into electric under-floor heating. The alternative, presumably, is that the energy is not used on site and exported, for which a tariff of 3.1 p/kWh. If his main form of heating costs more than 3.1 p/kWh (after local generation) then he's winning, save that the underfloor heating must never baulk use of PV electric for more important domestic electricity use. It would be immoral for him to deny this well-being to his family.

I agree about the desirability of improved underfloor insulation. But floors don't lose heat in quite the same way as walls and roofs because the heat does not escape into a system that immediately removes the heat into the wider environment - it will largely still be under the house. Which brings us to consideration of floor form factor and Table C1 of BS 13370. I'm surprised no one else has cited this yet. We don't know how big this floor is, nor the shape. If it's a large room, then the overall U value of the floor will be quite good even if it's sitting on a bare slab of concrete. Not as good as it would be with foam, but probably good enough.

emordnilap · Post by **emordnilap** » 29 Oct 2011, 21:14

Well said kenneal. We have to challenge the idea that any renewable energy is an addition; it should be a replacement for the polluting, climate changing stuff.

An Inspector Calls · Post by **An Inspector Calls** » 30 Oct 2011, 08:22

Which is what j2d does, reducing his use of ff to heat his home by substituting PV. It's better that he does this than exporting his PV and thereby wasting it heating the distribution tranformers in his local grid.