DamonHD

The Sunamp exposes a bare resistive immersion heater, nominal 2.8kW I think yes, more like 3kW+ at my typical supply voltage. Upstream I have a myenergi eddi that does modulation down to a few watts, generally from PV diversion. I also top-up from grid and do not allow more than ~2kW to be drawn fron grid. So the Sunamp can get the full 3kW on a very sunny day, or when my Enphase battery is able to kick in enough during a top up with 2kW from the grid. Rgds Damon

A Sunamp Thermino is working well for me: https://www.earth.org.uk/note-on-solar-DHW-for-16WW-UniQ-and-PV-diversion.html Rgds Damon

"Weeks" is really pushing it, especially for the UK. "It was found that almost all periods tagged as Dunkelflaute events (with a length of more than 24 h) are in November, December, and January for these countries. On average, there are 50–100 h of such events happening in each of these three months per year." https://www.researchgate.net/publication/355173603_A_Brief_Climatology_of_Dunkelflaute_Events_over_and_Surrounding_the_North_and_Baltic_Sea_Areas DECC used to worry about 5 day events; I believe that the German concern is ~6d. Rgds Damon

Do any of the dishwashers that you would consider actually have hot fill? In most cases new models don't in part because heating directly at the point of use is better in several regards. Rgds Damon

Thanks for the correction!

You should (must) talk to whoever administers your FiTs before making changes to anything involving microgeneration or electrical storage.

FWIW I have used RPis back to back for many years and I have had no sign of any SD card wearing out. I do take some precautions to reduce storage traffic, eg: https://www.earth.org.uk/note-on-site-technicals-70.html#2023-03-04 Rgds Damon

Somehow you have http rather than https in your address bar. Most recent browsers will default to https. Are you running a very old one?

FWIW hl.co.uk does an Active Savings thing that puts everything in one place to reduce admin, and has enough participants at the moment that you can spread over several separate banking licences.

The last time I bought a VA replacement part it was not from VA directly since they wouldn't talk to me as an end user. I used https://www.uk-spares.com/ Rgds Damon

Should someone even be trying to heat a large conservatory in the depths of a severe winter beyond frost protection? Rgds Damon

I think that we count as lowish water users. The Thermino covers 1 x bath and 1 x shower comfortably. (~4kWh and ~2kWh). Write up on whole system in tedious detail! https://www.earth.org.uk/note-on-solar-DHW-for-16WW-UniQ-and-PV-diversion.html Rgds Damon

For us the Thermino 150 (~7kWh) seems to have worked out about perfect in terms of DHW availabilty and physical size. (3 bedoom London home: 2 adults + 2 teens.) I have just today turned off the gas combi entirely (as a test, for at least a week or so) and do not expect to hear any shrieks from unexpected cold showers. Rgds Damon

Hi, Not sure that I have any of that wisdom stuff to dispense, and I am in the middle of preparing for a meeting, but here is some of my write-up which may be useful (follow the "See also" links in the sidebar): https://www.earth.org.uk/note-on-Spacetherm-aerogel-thermal-insulation.html Rgds Damon

This thread is amazing, thanks @JamesPa and everyone else! FWIW I came across this rather good paper: https://www.gov.uk/government/publications/cost-optimal-domestic-electrification-code which talks about total cost of ownership of various electrified alternatives to gas heating, ie including the CAPEX and OPEX. Rgds Damon PS. I have an ulterior motive to be following this thread: I have started research to try to make this decarbonisation of heat (for UK homes already standing) work as well as possible: https://www.earth.org.uk/PhD-research.html

At our ~100W typical peak overnight load the Enphase covers ~95% of it (actually it overshoots a little to compensate and then rows back). When the fridge isn't running and we only have ~20W of other 'vampire'/residual loads, the Enphase covers ~75%. With the UK 500W-minimum unit, none of those loads would be covered at all. Rgds Damon

The Enphase seems to have a threshold of about 5W in either direction before stepping in (if it can, ie when not full/empty). When I asked the tech director of the next best brand at the time he said that theirs was about 30W. One UK manufacturer's director that I spoke to said their unit was 500W minimum to intervene, though he did at least listen to my observation that my night load peaked at ~100W including the fridge, and our day load would rarely hit 500W, so their unit would not actually be much use to us! OTOH, the *peak* charge/discharge rate of my system is ~1kW, so it does not fully cover the peaky things such as the dishwasher or the oven, so I prefer to run the former when the sun is out or in the dead of night when grid demand is low. Rgds Damon PS. Saga starts here: https://www.earth.org.uk/Enphase-AC-Battery-REVIEW.html

I may be misunderstanding, but I do get to essentially 0 imports on some days, eg when we are away or have no large loads outside sunny times. Look at the data under here for example: https://www.earth.org.uk/energy-series-dataset.html#V-imp Partly I picked the Enphase ACB system to have very low import/export threshold before stepping in. Rgds Damon

https://heatpumpmonitor.org/

Has the heater relay simply failed open/off? Rgds Damon

Here's a couple that I am using: https://www.earth.org.uk/MHRV-mechanical-heat-recovery-ventilation.html https://www.earth.org.uk/MHRV-Vent-Axia-Lo-Carbon-Tempra-P-REVIEW.html Yes, I think they do their job. Yes, I also see condensation dripping outside from the bathroom MHRV. Rgds Damon

FWIW, the boiler was fixed and then given a thorough service: https://www.earth.org.uk/note-on-combi-replacement-dilemma.html#2022-10-04 And should it actually pack in, sensible boiler man tells me that second-hand condensing boilers can be had for £200 or so. Rgds Damon

It should help. Rgds Damon

There's unlikely to be enough potential solar gain in winter to be significant: the insulation value of an extra layer of material probably outweighs it. Rgds Damon

I have used aerogel to good effect in my own home, in several varieties: https://www.earth.org.uk/note-on-Spacetherm-aerogel-thermal-insulation.html Blinds are unlikely IMHO to be air-tight enough to be much good to retain heat. To keep sun/heat out: https://www.earth.org.uk/towards-a-LZC-home.html#reflblinds Rgds Damon