SteamyTea

Seems a simple way to control it. It should stop the HP doing something that is impossible, i.e. reach a fixed output temperature when the input temperature is extremely low.

Is that how your HP controls temperature by keeping the pressure within fixed limits? PV/T = C and all that.

Just done a quick chart about a heating curve. Assumed 3 different power levels, half power, ideal power and double power, the numbers are for reference and not actual power. Because heating starts rapidly, then slows, for any power input, it should be possible to initially run a heat source at lower power for a set time, then ramp up power later on. This could be useful if using PV to supplement the grid supply as it would reduce imports. It may also be useful to reduce cycling and frosting.

I misread that with an N in it.

I think you get caught with unexpected employment law and taxes, i.e. you have to pay minimum wage. Self builders are except from CIL, but companies are not. Think the VAT is different as well.

Or build that first, on a crushed brick foundation. Then move into the 'shed'.

Energy is sold by the half hour block, but it is sold usually the day before, though there are long term contracts (CfD and so forth). The generation companies need to know that they can supply the energy that they have sold, or they have to buy from companies that have excess. When they buy in at short notice, it costs them dear. So it is not as simple as Net Metering, as it was called before the FiTs came along. When only half a dozen 'hippies' like our @DamonHD had installed PV, it did not matter what they got paid, or not paid, their cumulative generation was tiny, not enough to affect even the local grid, let alone the national one. It has to be remembered that the FiTs and the RHI, were set up to encourage the domestic RE sector to expand, not to purely reward householders. That was where the big mistake was made, and how we got into this nonsense about pay back times and amounts. Having said that, it did massively expand the sector, you can't fail to see how many plumbers and electricians have 'Renewables' sign written on their vans. I think one of the mistakes made was not allowing the local DNO's to administer connections i.e. a dynamic list that shows what can be connected and where. We got into a state where a street can have multiple micro generation installations that cause local problems, and the DNOs are expected to sort it out. Though we got caught when we installed 16 kWp on 4 properties in the same street. The DNO sent us a bill for a few thousand for a new transformer and cabling.

Trips to the tip will cost you about £2/50lt bag. SITA are thieving bastards, but then so where BIFFA. But I think they are now SUEZ.

This is a very important point. You will almost certainly find that the good trades are booked up and expensive. But having said that, some TF companies will arrange to do most of the initial work, and that is where the important thermal details are achieved. Apart from the nonsense about 'thermal mass', and we have loads of debates about it and the zombie refuses to die, all you are trying to achieve is an airtight box with low thermal conductivity. Not hard to achieve intellectually, just that detail and longevity of material interfaces can ruin it. Having said that, the Space Station has been floating about (actually constantly accelerating) for nearly a quarter of a century, and they keep adding extensions to it, but not by Bob the Builder.

I think the problem is that the quantity of energy from spare domestic properties is relatively small, and not when it is wanted. And why bother to offer more, they are getting it for 50 quid a MWh, which is slightly higher than the recent (before the silly rises) average price.

I like cutting in. Do it right it makes the rest of the job a doddle.

My sprayer is still in the box, lovely and clean.

Wow, that is the posh version of kW/h. Shall add that to my list.

And then store enough thermal energy for the next 17 hours. My off peak E7 is now 14p.kWh-1, so gas will have to more than triple in price to equal it.

There is a guy on here, from Wales, that refused point blank to try that. He gets upset that his ASHP is useless. Glad you got it sorted.

Gas was so cheap, doubling the price still makes it a third of the price of electricity. Get a heat pump if you don't have gas.

And, at night, you can pretend you are s sniper. Best buy at Lidl mine was. That's your neighbour that is, checking up on you.

Yes, and design it to make full use of the PV modules on the roof. Could make something really quite good and useful, and a place to put lots of batteries/heat store in to soak up some excess generation. May even be able to 'split' a system so some is totally off grid, therefore keeping within the 16A per phase generation limit. On my weekly trips up country, I stop for a coffee in the Cotswolds.

Shame the one @PeterWsuggested only has a 2 year warranty. My twin impeller show pump has lasted over 13 years now. Was a 100 quid from Screwfix.

Why is your usage so high if you do not have an EV already?

Totally different dynamics. Lots of windows, very leaky, small volume, so disproportionate large surface area, floor area open to the elements. And an inch or two of insulation. They really can't be compared to even a 1970s house.

Your best options are to reduce losses as much as possible, then find a way to self generate. Some PV and a couple of small wind turbines, around 4 kW each, would supply you with a fair amount of power.

Been like that all day. Basically, 1 kWp of installed capacity will generate 1000 kWh.year-1. A single module is about 1 m by 1.6 m, so an area of 1.6 m2, and has a peak power of 330 W. So 3 modules gets you close to 1 kWp. 4.8 m2. These have to be set at at optimal angle, luckily PVGIS can sort this out for your location. If you have ever driven past a large solar farm, you may have wondered why there are large gaps between the rows of modules. This is to reduce shading when the sun is low in the sky. Shading is a real killer for PV, you don't need much of a shadow on module to seriously reduce performance. That is any shadow, it does not have to be contiguous. So trees, shrub, hedges, houses garden furniture or flag poles can cause a problem. This basically means that ground mounted takes up more surface area than roof mounted, so what may seem like a large area, may not allow that many modules on it. Can you put some on your roof?

I seem to remember that anything over 9 m2, which is under 2 kWp, needs planning permission. I may be wrong on that, rules change.

I think a few institutions, government agencies and architects have tried. None have worked as designed as the parasitic losses and large temperature differences in winter put a stop to this. But why try, get a HP and use energy that is already stored in the ground, water or air. My house needs around 25 kWh.day-1 in the depth of winter i.e. half of December, all off Jan and half of Feb. So around 1500 kWh. If I could store that in shortage heater bricks which have a SHC of around 2 kJ.kg-1.K-1 and charged them with solar thermal to 70°C, (actually does not matter how they are charged) but using a minimum draw off temperature of 40°C, I would need 90 tonnes of them. Around 30 m3. To reduce the losses to an average of 2 kWh.day-1, and assuming a cube for the store (3.1 m each side), the surface area would be a shade under 58 m2. Using a thermal conductivity of 0.02 W.m-1.K-1 for insulation, the insulation would need to be 0.62 m thick, that would increase the sides of the cube to 4.34 m, and the total volume to 82 m3. This would fill the ground floor of my house. And it would still not be enough in reality. So to store enough energy to run a house, you have to fill the house with storage.