SteamyTea

I usually get quips, but this one has passed me by. I am having a bad day. Got new bank card, took it to bank to get it activated as I was there anyway. They can't activate it, only the cash machine can. Put it in, checked balance and all is fine. Since then, done 4 transactions, only 3 have worked. 40 minutes on phone waiting for someone to answer 'because of COVID-19'. Did try the online chat, only to find out it is a chat-bot that does not understand 'my new card is not working'. Been a waste of a day off. Oh, and two of my family members, and their families have had it. And of course, Tim Brooke-Taylor died of it.

Could save me up to 50p a day. But all sarcasm aside, I could put in a wet heating system and gave more control. But for just me it is not worth it, yet.

How would you feel if your house was 48m². And then you have to take off about 10m² for bathroom and landing\staircase? My old neighbours, 2 adults, 2 teenage boys lived like that for years. So I cannot agree that we should not build bigger. We need to build better. That way it is easy to make net zero energy homes, you can't do that with only 2 kW of PV on the roof and walls with only 60mm of insulation. Oh, and a garden not big enough to put an ASHP in.

How long ago? Because

As far as I know the standards are the same. There is no exemption based on projected usage. But realistically, as we have the smallest housing in the EU, we should be looking at building larger places.

I doubt a tiny house could meet energy standards, too much surface area.

Relax planning laws and building standard.

As I was pointing out earlier, this does not always optimise the generation/storage combination. It is that optimisation where thermal storage has a problem, almost regardless of scale. Scaling really just reduces losses per unit stored. Yes you can, and you could make use of the latent heat as it changes from gas to liquid, it is how most solar thermal evacuated tubes work. 334 kJ/kg as opposed to 4.18 kJ/kg. Would need a sturdy box to keep it in.

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.