Sustainable Homes website

[Archie_tect]

You may be interested in following up renewable energy leads highlighted in the Sustainable Homes website- link attached. It also follows up the CSR and how that may impact on housing in Britain in future.

If nothing else it's an insight into how technology is changing in the renewable energy market and where help is available.

http://www.sustainab...a8-0ab81d01a3a0

[If you think this should have been in P&L, sorry- didn't think of that- could it be moved easily Shaun?]

 

[XmisterIS]

This area is of real interest to me; I recently went to see a sustainable homes "exhibition" (i.e. a tour of various green properties) in Stroud when I went to stay with a council member who is a friend of XmrsIS.

We saw some really nice self-build places, some of which were "negative-energy" houses - i.e. they generated more electricity than they consumed (on average) and actually made a profit by selling energy back to the national grid.

And the cost of building a spacious, open-plan 5-bedroom negative-energy house? approx. £170K!!

We were also introduced to this stuff, which is amazing: http://www.proctorgroup.com/Products/ThermalInsulation/Spacetherm.aspx

 

[summerdays]

No don't put this in P+L ... its of interest to me... we are at the moment going through the investigative stages of solar, with someone coming around to give us a quote very soon. Though I leave most of the technical details to Mr Summerdays.

 

[Archie_tect]

No don't put this in P+L ... its of interest to me... we are at the moment going through the investigative stages of solar, with someone coming around to give us a quote very soon. Though I leave most of the technical details to Mr Summerdays.

Solar heating or PV?

 

[summerdays]

Possibly both ... definitely think we are going with the PV... it will be interesting to see the size of the quotes and what they actually say with regards to whether it is suitable and amount we could produce.

 

[Archie_tect]

Possibly both ... definitely think we are going with the PV... it will be interesting to see the size of the quotes and what they actually say with regards to whether it is suitable and amount we could produce.

Needs to be within SE to SW arc and best roof pitch is 30 degrees. PV must not be overshadowed by anything on sun's path, otherwise it kills the electric generation as the panels are in series.

Cheapest on Housing Association housing on a NE site so far is:

Around £2400 +VAT for solar heating 2x 2.6sqm flat glass panels serving 2/3P bungalow [requires new hot water cylinder if yours hasn't got a dual coil in it.] Why everyone doesn't fit solar heating I can't imagine- but been in conversations about how private landlords are not interested in investments that don't give them a return [PV would if the electric is included in the rental].

£10,000 to £12,000 + VAT for 3kW array [retrofit not built in] giving Feed In Tariff return of around £900 per year for next 25 years+ you'll be saving the cost of the electric generated while prices are rocketing. If you have to borrow the money with a loan then probably it's not worth it, but if you have the money sitting in the bank then it doesn't make sense not to go-ahead as an investment.

 

[summerdays]

Roof is south facing ... no idea on the pitch ... at a guess slightly more than 30. We wouldn't be taking out a loan AFAIK.

 

[Archie_tect]

Roof is south facing ... no idea on the pitch ... at a guess slightly more than 30. We wouldn't be taking out a loan AFAIK.

Sounds perfect- lucky you.... mine's ESE/WNW so solar on the ESE would just about be worth it especially with directable evacuated tubes instead of flat plate collectors for solar heating but not for PV especially as there's a gable projection and a large crack willow tree in the way too.

 

[Yellow Fang]

Now could be the time to do it. I was at The Big Green Home Show today. The guy giving the talk said there were 500 installations in April but 2500 by September. He reckoned if demand took off to much, Ofgem would put a cap on it. The FIT goes down in 2012. Installation costs may go down as well, but if you want the full 41p per unit, don't leave it too late.

 

[yello]

Personally, I'm not (yet) convinced with PV because of the cost issues. I think its current payback period is too long (unless you have loads of space for many cells) and, in all likelihood, the technology will be both cheaper and more efficient well within that time period.

Here in France it only seems to be cost effective for farmers etc who have masses of roof space on barns etc. Your average home, in a decent sun area, seem to be quoting something like 15 or 20 years before payback. But I don't know how the French tariff compares to the UK one.

 

[Archie_tect]

Personally, I'm not (yet) convinced with PV because of the cost issues. I think its current payback period is too long (unless you have loads of space for many cells) and, in all likelihood, the technology will be both cheaper and more efficient well within that time period.

Here in France it only seems to be cost effective for farmers etc who have masses of roof space on barns etc. Your average home, in a decent sun area, seem to be quoting something like 15 or 20 years before payback. But I don't know how the French tariff compares to the UK one.

Don't knock it until you have checked it out yello- there are advantages. The French and Germans have been taking advantage of 60c per unit Feed in Tarrifs for over 2 years so if you have a south facing roof between 30 and say 35 degrees [depending on where you are], PROVIDING YOU HAVE THE MONEY IN THE BANK DOING NOTHING, it makes perfect sese to install PV as an investment.

As you say the technology will improve and become cheaper but then if everybody did this nobody would ever buy anything as they would be waiting for something better to come along.

If the Feed In Tarrifs were to be withdrawn then you would rely only on savings made from the generation which would be dependent on the size of the PV array you have but this is not insignificant due to the likelyy rise in charges ver the next 25 years.

Some electric companies and entrepreneurs are now buying up long term leases on existing roofs so that they then put PV arrays on roofs on behalf of the building owner and pay them approximately 20 to 25% of the return they can get from Feed in Tarrifs.

Many farmers have put vast PV systems on their existing buildings in France as you say because they have the money to do so without borrowing which makes perfect sense. Pay back is down to around 9 to 12 years on a domestic installation of about 3kW, enough to run your lighting, TV, fridge and computers, but not your heating or cooking. One farmer has been building holiday let chalets with full PV on the roofs. He earns more from the FITs than he does from the lettings.

You don't have to do it, and its a perfectly reasonable argument to wait and see what happens, especially if you'd have to borrow the money at bank rates which is not economic and would cost afr more than the return you'd get.

 

[yello]

We've also had a bit of a scandal here of late, unreliable or unqualified installers cocking up the installs etc. It's all added a bit of a nasty taste to PV.

We actually do have the cash to do an install if we wanted, and a large south-westerly facing roof over 35 degree pitch, so maybe it's worth me looking at again. The thing that put me off was the cost and the payback period. IF it is down to 9 to 12 years then it maybe worth looking at. Maybe I'll see if one of the local energy firms can do a study for us.

As you say the technology will improve and become cheaper but then if everybody did this nobody would ever buy anything as they would be waiting for something better to come along.

I appreciate that! My thinking was the improvements would be around the corner. IF you've projected a payback of 20 years (say) and then in 5 years time the technology is there to half that, then it it'd be a tad galling! I was going to review in a couple of years time.

Some electric companies and entrepreneurs are now buying up long term leases on existing roofs so that they then put PV arrays on roofs on behalf of the building owner and pay them approximately 20 to 25% of the return they can get from Feed in Tarrifs.

Interestingly, one of our local communes is going to install a field of PV cells (or the field is to be leased to a PV installation, one of the other!) purely as a revenue generation exercise... so there must be some money in it!

 

[yello]

Just reading something from the link in the OP

Your house remains connected to the national grid, and when you are generating more electricity than you are using the excess flows into the grid.

I'm pretty sure it works differently in France (somewhat bizarely). I thought, and I stand to be corrected, that you sold everything you generated back to the grid. You don't use any of it yourself.

 

[summerdays]

One thing that I want to know ... (and I have primed Mr Summerdays to ask at the consultation this week), what happens in the event of a power cut... will we have a small amount of power (depending on the light at the time - of course most power cuts seem to be in the evening!!) or does it not work like that?

 

[Archie_tect]

The only way to retain power is to have batteries but that would be outside the Feed in Tarrif arrangement. But I take your point- normally the generated power is fed into the mains [effectively a 2 way 'flow' ] which can't be independently used on the generation site. But i will ask as it makes perfect sense if you could!

PV generates DC which is then converted to AC to feed into the mains but I don't see why you couldn't have a trip switch which diverted it in the case of a power cut for your use first.