Sun, 12 Apr 2026 04:10:51 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302733#Comment_302733 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302733#Comment_302733 Fri, 04 Aug 2023 19:58:47 +0100 Diarmid https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302734#Comment_302734 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302734#Comment_302734 Fri, 04 Aug 2023 20:21:01 +0100 djh
When you say "I would have the solar PV feed directed to heat water by default" do you mean using a diverter? That's reasonable but it may make sense to use the heat pump to heat water in the winter (and maybe in spring and autumn too)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302735#Comment_302735 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302735#Comment_302735 Fri, 04 Aug 2023 21:10:37 +0100 Diarmid https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302779#Comment_302779 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302779#Comment_302779 Mon, 07 Aug 2023 16:19:56 +0100 GreenPaddy
- a regular nominal 4kWp array might give you 3000kWh of energy per year

- the PV array would likely give about (prob less) 1000kWh over the Oct-Apr (incl) heating period

- you prob use about 7000kWh of energy for heating

- so you'll need say 2000kWh of elect to get that from your ASHP

- you may well use more than that (PV generated) 1000kWh of elect in that heating period for non-heating elect usage (fridge/frzr, lighting, TV, computers, etc).

Basically, there's no correlation between solar PV arrays and heating sources (in normal domestic sizes). That's not to say having PV and an ASHP is not a good idea.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302780#Comment_302780 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302780#Comment_302780 Mon, 07 Aug 2023 16:20:13 +0100 GreenPaddy https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302783#Comment_302783 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302783#Comment_302783 Mon, 07 Aug 2023 21:27:00 +0100 djh Posted By: GreenPaddythere's no correlation between solar PV arrays and heating sourcesIndeed, that's why I bought a share of a Ripple turbine.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302802#Comment_302802 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302802#Comment_302802 Thu, 10 Aug 2023 08:40:19 +0100 Diarmid https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302809#Comment_302809 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302809#Comment_302809 Sat, 12 Aug 2023 08:43:52 +0100 jms452
The smaller the heat pump the better - part of why it works nicely for us is that we have 4kW PV and a circa 800W (input) Air to Air (A2A) heat pump. i.e. we're normally exporting a few hundred watts even when it's horrible.

As our A2A doesn't do hot water we've recently added a Eddie immersion diverter that heats the hot water in any gaps when the A2A isn't running or is throttled right back.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302811#Comment_302811 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17916&Focus=302811#Comment_302811 Sat, 12 Aug 2023 19:34:28 +0100 revor