[Bluedave]

  We were hoping to have them in place for this summer but a lot depends on how quickly the planners move as we need  planning permission even tho its only a domestic system.

Do you live in a conservation area? If not then you shouldn't require planning permission or it should be a formality. There was some legislation last year or the year before to make it easier to install domestic size systems - I can try and dig it out for you if you like.

[Spana]

Do you live in a conservation area? If not then you shouldn't require planning permission or it should be a formality. There was some legislation last year or the year before to make it easier to install domestic size systems - I can try and dig it out for you if you like.

yes please, if you can find it easily.  Thanks

We didn't think we would need it at first but after reading all the info from the planners it seems that we do.  Its because they are being mounted on the ground not on the roof.  She did say there shouldn't be a problem but its all extra expense.
The site is unshaded, direct south at the top of a bank and can't be seen by anyone. Planning seems  unnecessary to me, but there you go

[Bluedave]

oh sorry, missed that bit. You will need planning on the ground - change of use - still should be a formality unless you've got something odd in your deeds or it's agricultural land.

[Spana]

There are some advantages to mounting the panels on the ground .  They should be easier to keep clean, no scaffolding costs and it appears the fire brigade are reluctant to attend a house fire where the house has PV panels on the roof :blink: 

[madcat]

Our local planners (in a conservation area) are great  ...  they really try to help.   Actually, that is true of most things (no, I'm not related to one and I dont have a planning application in progress), but particularly with green agenda stuff.  Planners are humans after all - they just have daft rules that they are instructed to follow!

[Vit]

1) PV cells have about 10% efficiency, so use that electricity for heating is ummm "not optimal" 
2) solar water panels for heating will be more efficient
3) heatpump(air feeded exterior unit) working well when outside temperature above 0, but depends on coolant
4) proper insulation and glazing is most efficient to cut out bills

[John]

4) proper insulation and glazing is most efficient to cut out bills

It's always far more cost-efficient in terms of carbon reduction and, therefore, green to save energy rather than generate it although the feed in tariffs have distorted the economics so it might not make the same financial sense

[JohnB]

I'm dead keen on installing a very minor 12volt solar panel system in our home. We tend to get depressingly frequent power outages here, and it would be interesting to see what we could run and for how long on a small scale system.
As for the air source heat pump, I'm interested but know very little about them. I'd say go and have a look at the ones installed, and see how the owners home/ lifestyle compares to yours. I'd love to hear how the people get on with it, and whether they find they need to have any other type of supplementary heating, and if so, what-and for how long?

  Think about a real and cheap alternative :- a generator. 2.6 kw generator selling in Aldi or Lidll can't remember which £170. Theres your lights computer telly and a microwave sorted in one go. Probably your central heating (pump etc)

[JohnB]

4) proper insulation and glazing is most efficient to cut out bills

It's always far more cost-efficient in terms of carbon reduction and, therefore, green to save energy rather than generate it although the feed in tariffs have distorted the economics so it might not make the same financial sense

  I am afraid for a lot of people carbon reduction is all about conspicuous consumption IE look what I am doing for the environment when in reality they have taken no account of the cost to the environment (in terms of carbon creation) of creating for instance wind farms and solar panels. Is it sensibly for instance to reduce carbon by a ton a year and create a 100 tons doing it? With a device which will last only 20 years? We are at the moment paying out 40p a KWh for renewable energy and charging 10p a KWh or less to the consumer. That alones says a lot about just how environmentally inefficient some if not most renewable energy sources are. Never mind the future for electricity prices??
     

[John]

JohnB - that is very well put! The real reason I would look at PV or a turbine is to use it as a retirement investment based on the FIT. Our REAL carbon savings come from mundane, boring loft insulation etc.
Eventually our investment of time, effort and a little money in trees will provide us with free fuel but that's not a route open to people without a lot of land.

[JohnB]

JohnB - that is very well put! The real reason I would look at PV or a turbine is to use it as a retirement investment based on the FIT. Our REAL carbon savings come from mundane, boring loft insulation etc.
Eventually our investment of time, effort and a little money in trees will provide us with free fuel but that's not a route open to people without a lot of land.

Remember what I said about the new roof turbines? the article was in the Sunday Times. Also I have my doubts that they will continue to pay 40p for something they can only sell for 10p Morover there is nothing to stop them changing the amount they pay in the futore unless there is a specific contract. I read they have reduced the amount they are paying to some renewable energy comapanies although the articles was not very specific. You could consider coming off grid if you could store the electric. A farmer In Lincolnshire had a new farmhouse built and all estimates for bringing electric to him were higher than having a large wind turbine and batteries (£30,000). He did live on the flat part and obviously he could not sell the electric.
   Fire wood look at coppicing to get the wood quicker and to save splitting it.
    I have the required amount of Insulation which I think is 10" or 12" is that right? Either way I took up a bargain offer a year ago of 170mm insulation at a £1 a roll. It is either a double or treble roll depending on the width of your joists. My neighbour said i shouldn't lay it as the benefits are minimal and it can course condensation. What do you think/know? espcialy on the increased insulation value or lack of it. If it is of minimal benfit or and courses condensation I would rather give it away, what do you reckon?
PS my neighbour is a builder.

[John]

I'm well aware that rooftop turbines are not a good idea domestically, we've got some windswept fields facing to the prevailing wind so was thinking of a 15Kw installation. First stage is to erect a tower and measure the wind for a year.

There's a lot to consider beyond feasibility; - planning permission, lifespan and reliability of equipment and 'will the government stick to the deal'

Some years back I did the calculations on insulation using the U values and all that. There is a law of diminishing returns. the recommended depth of loft insulation has grown from 4" to 6" to 12" as the price of energy has risen. Assuming it is, as threatened, going to jump again, it seems reasonable to assume greater depth will become recommended shortly after.

As for the condensation, not heard this. Assuming the roof isn't leaking and the ventilation into the loft is as required, I don't see it being a problem. I'd look around on some building forums or seek advice from energy saving trust if it's a concern. We do have some good builders on this forum if they care to comment, it would be appreciated.
 

[Vit]

When first electric lights appeared, "candle kings" did lot of things to kill invention. 
When internal combustion engines appeared, it was epoche of steam machines..... 
It's time to go solar now. When manufacturing will pass "critical mass" panels will be cheap as chips. Do you remember prices on the first cellphones? 
Another thing is that equipment is little bit overcharged - blablabla, hi-tec, blablabla, qualified engineers and installators.... But that guys doubling the price, just by connecting wires between factory made boxes following manual 
One more point is to use energy saving bulbs and LED bulbs

P.S. i have one crazy project in my mind how to build solar PV farm almost free, but it will take a bit time

[Bluedave]

Condensation will occur if there is not adequate ventilation in a building fabric designed to be ventilated (i.e. cold roof construction or cavity walls). This is why you should be careful of blocking up air vents/bricks in old Victorian buildings for example as they were designed in to stop condensation occuring within the building construction.

Under current building regulations the level of insulation is so great that they are now looking at reducing things like thermal bridging and air permeability as these have a much larger impact on heat losses then adding more insulation (i.e. John's point about diminishing returns).

Buildings are now becoming so well insulated and air tight that the next problem is adequate ventilation, condensation problems and summer overheating. I think in new build dwellings we have gone as far as we can with building fabric. The next challenge is fuel mix/type and decarbonising the grid (nuclear anyone.......).

Our new build stock is so well regulated that it uses very little energy. The government should look at the existing stock and use some of the 'renewable band wagon' money for improving the insulation levels in older stock.

[mumofstig]

The government should look at the existing stock and use some of the 'renewable band wagon' money for improving the insulation levels in older stock.

something I've been saying for a long while.
If fuel keeps rising in price as quickly as it has recently, all the old houses will be unsaleable.