solar panels - read the threads , still a simplevquestion.

A house I had in France had its gas tank buried in the garden, near the front gate, similar to this:

Ditto oil. We could use large cylinders but that would only do for cooking etc. and I prefer an electric cooker.

Battery backup power units specifically for boilers are available.

But what happens when the net zero mania hits and we cant use fossil fuels anymore?

TBH if you're primarily interested in heating then I'd look at a heat pump before solar. Solar will give you power in the spring/summer/autumn when you don't need so much heat, whereas a heat pump will reduce your electricity by a factor of ~3 in the winter when you use most electricity.

A battery might allow you to move some consumption from the daytime peak to the night off-peak, but it's not going to get you a great deal of storage - eg if you have large(ish) 10kWh battery that's only the output of a typical gas boiler for half an hour. E7 tariffs often have punitive daytime tariffs anyway, where it's cheaper just to be on a single rate unless you massively consume in the night time.

Often when people talk about heatpumps they mean the 'air to water' types that replace a boiler and heat radiators, but there are also 'air to air' types which are more like air conditioners. The latter are cheaper to install if you don't have pipework, but noisier (there's a fan blowing all the time you're heating, whereas radiators or underfloor heating are near silent). You also get air conditioning 'for free'. The 'boiler upgrade scheme' grant gives you £5K towards the water type, but the air2air can still work out cheaper without pipes. Air2air won't do hot water, but maybe you have an electric shower or other water heater anyway?

If you're worried about heating during power cuts and don't have a stove or other source of heat, invest in some portable gas bottle heaters. They aren't great as a full-time source of heat, but for the occasional winter storm they should stop you freezing.

Being all electric with a heatpump, our consumption is about 400kWh per month in the summer and 700-1000kWh in the winter, with the heating on a constant 19C all day, so the monthly heating/hot water consumption is 0 to

Theo

I always used to wonder why there weren't 12v pumps

When mine was installed, you would have got a very blank look had you mentioned zero carbon emissions.

Some of those made for boats look as though they would do the job.

Where friends of mine lived a few years ago the oil taker came with a very long hose that ran from the road, through the front door, through the house and out the back door and then to the tank. The hose could have reached a lot further. :)

I know of people using cylinders for central heating but I don't think it would be any cheaper than all electric (non-ASHP) heating plus it relies on having enough full cylinders to carry you through, say, the Christmas break and when the delivery company is busy.

It doesnt seem cost effective to run LPG or solid fuel.

Probably more cost effective than using electricity. However to take advantage of alternatives you have to ditch storage heaters and possibly use a circulation water based system.

Besides, boilers need electric to power them and I moted that when we had power cuts no one was any better off as their systems stopped working too.

You really seem to be struggling to really justify not having a smart meter and/or different heating systems. how many power cuts lasting more than 30 minutes have you had in the past 5 years?

If you are not keen on a smart meter nor solar why not work out when you will actually make any savings. A optimistic saving of £560 per year means that the break even point for a solar/battery combination is possible around 10 years.

Again from the link I previously posted.

The price of a typical 3.5 kilowatt-peak solar panel system is about £5,500. Based on the Energy Saving Trust's figures, it could take someone living in the middle of the country, in a typical home, anywhere between 10 and 17 years to recoup the costs of installing panels, based on current Energy Price Guarantee rates. This depends on how much electricity you use and when you use it, and what you're paid under the smart export guarantee. [/quote]

Yes you can. My next door neighbour has that. There is a metal frame that angles the panels at the appropriate angle.

I hope it was properly treated to prevent pest infestation. There have been some horror stories with new build eco 'green' houses that have used sheeps wool batts in the walls that were not treated correctly.

I would use the 12K pounds to improve your wall insulation.

Well, I am not really bothered about solar panels. Hubby is. I dont really know why. We get lots of power cuts here - up to eight hours after storms. We can have three or four of these a year. The only use I can see for solar panels is that they could run the freezer or similar during a long power cut. Personally, I would rather have a new kitchen than solar panels on the roof. I think Hubby must have seen or heard some programme about how good solar panels are or something.

When was this flat roof constructed ?. If it a 'cold roof' (most flat roofs done before 2005 were) then the big question is what insulation did the builder put above the ceiling and between the roof joists, and how well was it installed ?. Out of sight so impossible to check. Major source of heat loss.

When was it last re-felted ?. I think Part L requires the roofer to apply a layer of insulation on top of the deck and then apply the new felt on top of the insulation. The problem is that a flat roof built to 'cold roof' spec should have cross ventilation. This ventilation is *beneath* the deck with its new layer of insulation and simply renders the insulation ineffective. Blocking up the cross ventilation is a bad idea unless the ceiling below is overlaid with foil backed plasterboard with taped joints and edges to stop water vapour molecules migrating into the flat roof void where the new insulation would result in interstitial condensation. If you have downlighters then I guess it would be impossible to completely seal the roof void from water vapour ingress.

I already have wall insulation. I am sure its been treated ( the loft that is)

On the issue of damp. One thing I discovered that seems odd to me but is the case . I was checking damp walls in the bedroom and pulled off the wallpaper to check the walls to see where it must be coming from. I found the walls beneath the paper completely dry. The paper was sodden . It was painted woodchip, probably put on in the 1970's. I pulled all the paper off, painted the walls and havent any issues since. I did this in every room in the house afterwards. I had not looked at this previously because I was working. House arrest and wfh allowed me to find time to look at it.

That's classic condensation. The woodchip is impermable, so warm humid room air hits cold walls and condenses. The water can't soak into the wall so it sits on the surface, causing mould.

Get rid of the impermeable surface, insulate the wall so it's warmer, no more mould problem. Emulsion paint is permeable so it allows the wall to breathe and stops it collecting water on the surface.

Theo

It was common to paint woodchip with eggshell finish paint, which was oil-based and quite a good water vapour barrier. Also a pain to remove if the underlying wall/plaster is sound and dry.

Yes, but they need to be mounted on angled frames with several important caveats :-

Flat roofs need recovering every 15-20 years. The next time you have this done the roofer, if he is any good will tell you that he must fit insulation above the 'deck' after removing the old felt and apply the new 'felt over the top of the insulation. (See Part L of the building regs).

You live in a part of the country that is designated 'extra windy' by building regs and those panels are like sails. They need to be anchored down very securely. This is tricky with a flat roof, especially so when it has an extra layer of insulation (which it will need to have at some point). Be extremely suspicious of any solar PV company who might tell you that it is OK to fix the angled support frames by drilling through the felt and screwing into the joists supporting the decking.

Andrew snipped-for-privacy@btinternet.com wrote

We'll see...

Not when you use metal decking.

BULLSHIT. Completely routine in fact.

Works fine with metal decking.

F*ck me. The troll is still alive. Covid was not as good as I hoped.

But that's the first post you have made that said the hubby is "still keen" and not a useless wanker.

Or have you changed his knob from manual to automatic because of your disability?

Cheers

Adam

It's possible to fit them on angled plastic buckets that need no attachment to the roof, eg Renusol Console. The buckets are ballasted to prevent them getting blown away. You need to add sufficient ballast to suit the wind speeds at your location, for which there are calculators.

The buckets are simple to remove if you need to redo the roof: unscrew the panels from the bucket, unload the ballast, remove the lightweight plastic buckets. It helps is the ballast is portable (eg paving slabs) rather than loose (eg gravel).

The joists may not be designed to take upwards forces, so I agree this is risky - you don't want your joists blowing away as well as your panels. That's why you'd want a fairing to prevent the panels catching like sails, as well as ensuring the joists are anchored to the masonry (hurricane/wall plate straps or similar)

However I'm not sure attaching to the joists will be as big an issue as you suggest: it'll be a point of water ingress, and it'll be a cold bridge, but both of those can be mitigated with good detailing. I agree that cowboys not knowing how to do it is a risk.

Theo

The flat roof went on sometime in the 1960's or 70's. To my knowledge, its never been re felted. I have no kidea of the construction.