Originaltwist

Don't forget though that more vehicles already support V2L ... like a 3kW mains supply behind the front seats .... and you don't need an expensive charger for that. @Andehh - any suggestions for a suitable second hand EV with the right battery please.

Good advice above on the mini-split aircon idea. You might benefit from making one as part of the future strategy. So you install something like the Mitsubishi SRK60ZSX-WF Heat Pump for about £2,000 and then add to the plot with the UFH and presumably another heat pump to run it. It would be a shame to spend the same sort of money on expensive direct heating kit that then becomes redundant. The mini-split can be had with more than one blower thingy.

There's a huge difference between coil in the tank and a PHE. As the latter has to be pumped there is instant destratification in your tank so you call for power and the shower bizzarely goes cold. The wad of heat at the top of the tank put there by your solar diverter and immersion is worth preserving. BTW an external immersion heater like a Willis should be better for building that stratified wad of heat - easier to service too.

Yes - guilty as charged

Yes, ROI is challenging but if you have a heat pump to multiply the benefits then it heads into no-brainer territory.

Hello, welcome, and congratulations on your purchase. I love the rationale behind boat ownership and even went as far as dreaming up the perfect spec here https://wordpress.com/post/originaltwist.com/887 ... and yes of course it has a garage.

I sort of like this and if it had a built in booster to increase flow it would solve my particular shower issue then I'd like it even more. However; To connect all the pipework I'd have to rebuild my shower area. And as shower drain pipes can get sludged up with mould and slime how do you clean it? Would it go under the shower tray or on the wall? It looks like your market is for new shower installations and that crowd have a lot on their minds already so they will be risk averse. Selling something new, however good, is difficult and expensive. But good luck.

If that's a Clearview stove (Vision 500?) then you can just unscrew the nuts on the exit pipes, remove the boiler and order the missing rear fire brick. Then Robert's your father's brother.

The overwhelming wisdom from responders must lead you to the obvious conclusion to go ASHP. Your misgivings about winter performance are correct though - lower temperatures do lower the COP - but even so you'd have £10,000+ in hand to pay for the slightly higher running cost. Anyway, there are many days when the ASHP runs cheaper than GSHP especially in the second half of winter so which is best is arguable. You mention UFH throughout. I'd consider fan coil units for bedrooms where the slow response of floors doesn't match the requirements of cool sleeping time but warm getting up time. When you put in the 6kW ASHP, as suggested, fear not for being underpowered, just add a mini-split to top up and do the aircon. Normal pipe sizes will work, heating will be free on many sunny days with a bit of PV, life will be good.

Could we know how much power you are needing to make please.

I don't think there is startlingly good value here. A Fogstar 15kW.hr battery and a Victron Quattro-II would be under £5,000. This would be more versatile but you'd need to forget the string inverter idea for PV panels. Spend the saved £2,300 on some panels with Enphase micro-inverters, or maybe you already have some panels.

Just having a doodle on Sketchup. This is the germ of an idea for a heat pump technical room. It could be on the ground (facing south) or even on top of a flat roof. It’s like a green house but the wooden back wall has cut-outs for various vents. The idea behind the black plastic drums of water is that the sun warms them up during the day and during the night they give off heat to prevent some frost cycling on the ASHP. The shelf holds an ASHP unit with space for a mini-split unit as well. Why? A smaller heat pump solves many pipe size issues and a mini-split augments heating power while incorporating air-con. One or the other might often run free on PV panels. The units are protected from the elements and easy to work on. Under, or on, the shelf there could be a GSHP unit and those hexagonal mesh things are car radiators (boxed in with fans) for the combined air and ground system. It’s a good tweak to add a simple air side to a GSHP especially if space for burying slinkies is limited. The extra tank for this could be here or elsewhere. Daft or food for thought?

A few negative comments above drove me back to the Fogstar site for a closer look at the £2,500 15kW.hr battery. The cells are different from their more expensive 15kW.hr offering being the EVE prismatic ones but they are grade A. The charge rate and the discharge rate are the same at 200A. I doubt if anyone would use 200A either way. I can't find any stats on round trip efficiency. The life span is lower at 3,500 cycles on an 80% DOD yet there is an 8 year guarantee. Presumably if not drawing 200A the cycles might be extended but anyway once a day for about 10 years looks acceptable. BTW I have no affiliation here – just a curious potential buyer, so any negative comments are more than welcome. The following is clipped off their site. Unwavering Confidence in Quality: We stand behind the exceptional design and construction of our batteries, offering an industry-leading 8-year warranty and a 15 year shelf-life. Premium Grade A EVE Cells: The Fogstar Energy 15.5kWh Battery utilizes 16 premium LF304 Grade A EVE cells, renowned for their exceptional lifespan of 3500 cycles at a discharge rate of 200A per cycle.

I suggest you sit by the boiler with a stop watch to see if it's short cycling. My neighbour's oil boiler goes 'whoooof' about every 3 minutes - crazy.

I helped a friend go off grid on an AirBnb let shed. 1.2kW for £1,700 and it's been running for 4 years. With better panels and batteries you could easily get up and running for a lot less money and time than the connected supply. Have a look at the Bimble Solar web site for some package quotes. 1.2kW is a bit light but it is possible to plug in a hedge trimmer so a 5kW rig would be easily enough.

Have a look at 'Cheapest Heating Ever' thread to see how your running costs will be miles better with ASHP + battery + solar. And consider; Octopus heat pump offer. A smaller heat pump gets round a lot of pipe size issues, then add a mini-split to top up heating and do cooling. Having low power on the heat pumps means you can often run one free off the solar.

Wow - thank you everyone for your kind responses. This is definitely above my pay grade so I'll call in the pro's. I was hoping to find some gloop that I could brush on but if a job's worth doing .........

I have a 20 square metre breeze block wall with a crack in it. I'm looking to mend the crack and render the wall outside to waterproof it. I think the job is too small for a contractor. Is there something I can put on myself?

Before you go spending a lot of time and effort could I point out my recent experience with a mini-split. I had assumed that the cooling effect would be like the heating but just the opposite way round. Not so, when heating the effect is very localised but when cooling the cold air sinks down and spills across the floors. So one little mini-split is cooling the whole of our ground floor.

Mike - I've checked the Fogstar specs. It can deliver 200A so as a 50v battery that's 10kW. Being gentle with it and using 100A will match the 5kW on my favoured Quattro inverter. Re the comments on handling charges and inverter losses - totally relevant - I would point out that we are looking at a battery + heat pump argument, so all gains are multiplied up by the COP and losses are similarly mitigated. Putting away the spreadsheets for a mo, It looks like heat pump running costs are roughly halved with a battery (see chart above) so if you spent £5k on the rig and knocked £1,000 off your bill you'd be paid back in 5 years. Life expectancy is nearer 10 years (insert joke here). Losses - If all the kit is inside your heated envelope then they are more like efficiency setbacks but not really losses. I'm with @TonyT it's looking like a no brainer for heat pump owners.

The £2,500 job is plugged on their site as coming next month and can be reserved. Yes you'd need an inverter/charger. I got excited by the Victron Quattro-II because it has an extra AC input which could pull in an EV v2L feed. It's very expensive but opens up many possibilities and anyway a V2G charger is expensive too and this gets round that by using the V2L feature that many more cars have and the Leaf doesn't. I hadn't twigged the 1.8kW output - is that on the spec?

Batteries getting cheaper and no VAT 15kWh for £2,500 from Fogstar next month and no VAT Time shifted night rates running heat pump (with the COP uplift) make for an interesting comparison to the normal heating methods. I've tweaked a recent chart of the latest rates to show how good it could be. Of particular note is that the battery tweak elevates an existing heat pump from the worst spot on the chart to the best with a doubling of the output. Batteries used to reach the end of life before payback was reached but now ....?

As the issue is about gas emissions when the pipe is connected perhaps if the pipe was connected and precharged to one side and had a crafty device on the other end that opened as it was screwed in. So anyone can drill a hole in the wall, shove the pipes through and screw them on or maybe just push them on like airline quick connectors. BTW My A2A came from Saturn 18 months ago, under £1,000 total fitted with no fuss. Gas guy came with electrician for 4 hours. I guess that was lucky timing.

Not much cheer here although oil has fallen recently. However I see that battery prices have fallen (with lithium) and Fogstar are about to offer 15kW.hrs for £2,500 which is a total game changer. Time shifted night rates and heat pumps - nice. Looking for an inverter/charger for said battery I see that the Victron Quattro-II has a spare 240V input which could connect a V2L from a car (the plug behind the back seat on a few). That would be very interesting.