SteamyTea

It would just push up plot prices so that the overall price was the same. The housing market price is set by what people are paying/borrowing. Does anyone think that the average house price would be £231k if interest rates had been 8% for the last decade?

This is generally true for all storage, and generation for that matter. The thing about PCM is that the temperature is the same when it changes phase. It is almost the definition of it.

This is always a problem with inline heaters. One way around that may be to deliver say 6 kW from the batteries and 10 kW from the mains. Not idea, but would make for a decent enough shower. Or just heat a small cylinder up slowly. 50 litres of 65°C water mixed with 30 litres of 10°C water should do it. May need a small cylinder for each shower. 50 lt is a 0.36m cube.

Yes. But as you say, you have a small array and you use most of it. Not always going to be the same for everyone. It is up to individuals to work out what is best for them. There are other reasons to choose an MCS installation over a DIY or own contractor approach as well.

Yes. I could probably get 2 kWp on my roof. That would give me about 2 MWh/year. My usual day usage is a shade under 2 kWh, night usage is between 3 and 10 kWh. So at best, all I could do is offset that 2 kWh/day usage, and heat my water during the summer. The big cost of a small system is the non storage part, i.e. the charge controller and inverter. I would need a 6 kW inverter, that allows water heating and a kettle to be on, or a storage heater and the water. There are also export payments for excess generation, so those will have to be costed in, along with the cost of a suitable PV and storage system.

This is what got me thinking about it. Even if you just charged your batteries from your PV and then discharged them via your water heater, it may soon be financially viable. And you can always plug into the mains if needed. The control system should be fairly easy too, just state of charge, power diversion and timers.

Like all storage, it needs to be empty to take advantage of cheap or free energy. This may be OK for space heating, probably less so for DHW. Has anyone compared the prices to battery storage? If you are going to spend £3k to £5k on a Sunamp, it may not be so far off.

Have you looked at Draw, it is part of the LibreOffice suite. https://portableapps.com/apps/office/libreoffice_portable

Seems so, be interesting to see how it all works out longterm. We had skirting radiators when I was a kid. The gas boiler ran on town gas.

The technology behind the phase change and the vacuum insulation is well understood and documented. Just the control system and sales/after sales that is iffy. That is always a worrying sign, unless there is a court case pending. And I would ask for 'a treat' to stop me talking. I have heard and read a few things, but without a verifying first hand, it is still in the realms of substantial rumours at the moment, or it just ends up as a 'Me To' campaign.

Same here. Really comes down to price. Price is a good equaliser in many ways.

Is that because the system is over specified. I could probably get away with 50 litres of water at 45°C. But my cylinder is 200 lt. I don't run out.

That is a tricky one. You can design it to be heated by the HP to say 45°C and have a capacity that will meet your normal every days needs. Then, if you need more, just use an inbuilt resistance immersion heater to raise the temperature up to 65°. Think that is equivalent to increasing the capacity by 2.3 times (depends on what you consider to be an acceptable minimum temperature, I chose 30°C).

Aimed at anyone really.

Remind me of this of Guadi's house in Parc Guell.

Sometimes, fitting roof integrated PV can be cheaper than slating, is that an option at this stage.

Used to fit and service spa baths. The worse job I ever did was cleaning out the DE filter at the Sheffield YMCA. I have no idea what those young men got up to in it. Also got this https://www.healthline.com/health/hot-tub-folliculitis from the Bedford leisure centre spa bath. Only stood in for 2 minutes. "Hot tubs are the devil's own swimming pool." This does not even start to describe them.

You will need to block off the MVHR.

If it is like regular skirting board and is fitted onto an external wall, you will be increasing losses as you are heating up a cold wall that conducts directly to the cold outside.

Mixed units there, W is power, heat is J.

As I understand it, yes, just a rubber stamp, pass or fail. Pretty hard to fail in reality if some care has been taken. If there is a known problem, explain to the people that are pushing you to get it done that the country has been in lock down for 3 months, just in case they missed it. A few insurance companies are in Bournemouth, so they may have been on the beach.

I think they do. Do a text search on that SAP document I linked to earlier. With a small flat, I would have thought that ventilation was more important. I have a small house (smaller than some of your flats), if I lived up country, I would have fitted MVHR by now, as it is, I can get away with open windows for the majority of the year, though this does chuck out the heat I put in during the previous night. Worth remembering that when a storage heater is charging up, it shuts down most the the heating. Why they can be good working with PV, even in winter as you may only need a kWh or two a day to keep the chill of a place.

That is quite an interesting idea. Has anyone worked out the price difference between installing ordinary plasterboard and that aerogel backed plasterboard. Then compared that to say fitting a heat pump over a storage heater. I still think that one 10 kW inline water heater for all the hot taps and modern storage heaters is the cheapest option and the most environmentally benign. Does anyone have the proposed CO2 figured for grid supplied electricity that SAP is changing to? The 2018 SAP document Table 12 says 0.233 kg CO2/kWh with a primary energy factor correction of 1.738. Gas is 0.210 kg CO2/kWh with a primary energy factor of 1.122. So 0.405 and 0.236 respectively. But I am not sure if they are the latest numbers.

Thinking a little outside he box here. You could heat up one large cylinder with water, then feed off that to the 3 flats, via inline heaters. Does depend on how the water is metered. It is possible to fit PV on a roof at a lower cost that tiling, does depend on roof design. You may also find that fitting a 4th meter and exporting everything that get generated, while collective the 5p/kWh (or whatever you can negotiate) is a better way. I think you will find that the 'government' is doing more that you think. Also a lot cheaper to build a solar farm than get a few thousand panels fitted to new builds. Really need to do both though, but people still think that PV is expensive, don't work well and will break down.

Exactly. They may not be perfect, but still pretty good, and one can always add more insulation inside the airing cupboard, worked a treat for me. He had one of those horrible cylinders where the feed and header tank was combined. And then it was more a problem where it was situated as the power loss was heating up the bedroom. I like the technology of the SA, but they are too expensive and have control limitations.