So a customer of mine is thinking about getting either or both instaled,Knowing little about them, but am thinking theyre good for the enviroment, the same as the customer.

2 points struck us, why dont the big electricity companies fund the instalation of them, instead of using contractors, and what if the contractor goes bust who carries out the relevant replacemet or repair, if they ever break down.
and are they a worthwhile investment

2 points struck us, why dont the big electricity companies fund the instalation of them

Would you ask a drug dealer to fund the local police so they can sell less of their product?
IMO, it is only the legislation that makes power companies do the insulation thing etc.

and are they a worthwhile investment

Solar: YES, YES, YES for water heating, yes for PV electric panels.
Small wind: NO. We have 2x Proven 6Kw, on a windy Scottish hillside. Nearly perfect site. Yet they will never pay the economic or environmental cost of constructing them, and cost more to service each year than they generate.
Power output of wind turbines = the square of the blade size. So half the blade size = 1/4 the power. Keep scaling back the economics, and it does not work. Mind, make em big huuuuge and chuck em out to sea and they rock…

http://www.energysavingtrust.org.uk/Generating-energy/Getting-started-with-renewables

hold on… the govts green deal due to be ‘live’ in the new year addresses just this question. recognising the costs involved introducing carbon reduced energy to the home you ll be eligble to borrow 6500 to have work such as you detailed done to a property. you ll pay the money bac over 20 years via your electric/ gas bills. the loan isnt yours its the properties so if you move you stop paying and the new owner takes up the slack..

Yes.

Installed 21st Feb 2012 – 3.99kw system – so far produced 2900kw/h – income £1300 – Saving in household electricity bill 30%

I presume that is PV? What was initial cost?

Also if you move out of the house who pays the debt, and intrest on the loan and does the new owner inherit any warranty.

Also if you move out of the house who pays the debt, and intrest on the loan and does the new owner inherit any warranty.

With the Green Deal the house owns the debt and is repaid through the fuel bill. You move and the debt stays with the house and doesn’t move with the owner.
While current figure are attractive, be carful as the FIT (Feed in tariff) is reduced. Look at lifestyle too.
http://www.decc.gov.uk/en/content/cms/tackling/green_deal/green_deal.aspx

You move and the debt stays with the house and doesn’t move with the owner.

So putting off any buyer…

So putting off any buyer…

Not really because the ROI can be spectacular.

Installed 21st Feb 2012 – 3.99kw system – so far produced 2900kw/h – income £1300 – Saving in household electricity bill 30%

Insulating properly is the best investment.

Power output of wind turbines = the square of the blade size

*cough* swept area isn’t it? *cough*

Insulating properly is the best investment.

^This, by a long way.

My property was built in 2003. U Value of the roof is probably 0.35. I could add another layer of quilt and drop this down to a 0.2.

Say 60m2 foot print. Saving would be 0.15 x 60m = 9 watts per degree C over the roof area. So say 18degrees inside and 2degree outside total loss = 9×16 = 144 watts.

£7800 cost for PVs. Return on investment circa 20%.

Would agree you need to check current FITs tarrif and PV cost.

So you could save 3.5kWh a day just by improving your roof insulation to R5, pjm84. I don’t know how much you pay per kWh of heat but I suspect you would save about £80 a year. Given how cheap roof insulation is, what’s stopping you?

U Value of the roof is probably 0.35

As designed/specified – not *actual* which is usually a *lot* worse than designed. Also no account taken of cold bridging at junctions and joints in that statement, which again in ‘real world as built’ accounts for as much heat lost as the rest of the wall or roof…

3.5kw/h over a 24hr period.

I sleep at night with the window open and no heating. So this morning it was 0 degree (car temp). We did not have the heating on but it was cold. So lets keep it simple. Lets say 12hrs heating a day (energy imput / cost) for 4 months. In effect 2/12th of the £80 saving above. About £14.

The above is simplistic but it gives you an idea.

I’m not ruling it out but will probably do the semi exposed floor over the internal garage as this is the weak detail in the house. Still its nice and cool in that room.

Cold bridging is minimized. 2 rolls of insulation. One roll between the trusses, one over. Good installation on my roof, I’ve checked and I’m qualified to do so 😉

Fully aware of cold bridging and contractors (No valley layboards on my roof though – FFS).

The loft hatch is the weak spot. GRP unit with 15 or 20mm EPS backing.

Wind turbines from about 15kW and above are great in terms of return on investment but the little ones are awful. E.g. and Endurance e3120 (32m base to blade tip0 will cost £260k installed but generate £45-70k a year and a 500kW one generally (47-65m base to tip) will pay off in 3-4 years i.e. £350-520k a year at a good site. Little ones generally take 6-10 years.
Solar thermal’s great if you use a lot of gas for heating.
Oh, and don’t underestimate insulation, it has the best cost benefit ratio of anything.

Green Deal really isn’t for PV or solar water heating, you’re better off claiming FIT and RHI (when available). You probably won’t be able to claim for either if you have the units installed through Green Deal.

Green Deal/ECO is good for insulation especially if you live in a hard to treat house (solid wall or off the gas network). Should be some subsidies available if living in a HTT home.

Check out page 11 for the list of qualifying measures for ECO subsidies http://www.decc.gov.uk/assets/decc/11/tackling-climate-change/green-deal/5504-which-energy-efficiency-improvements-qualify-for-g.pdf

the qualification for the subsidies are:

Affordable warmth – on a benefit of some sort (there’s a specific list of those that qualify)
Carbon reduction – anyone who lives in a HTT home. You would have to pay for the measure up until the measure stops paying for itself in it’s own lifetime – ECO provides the rest.
Carbon saving communities – homes in low income areas (the lowest 15% in the country).

Green Deal and ECO are available in England, Wales, Scotland but not Northern Ireland.