[_oyks]

Yeah, had to get clued up on this for new house in London. A few points:

1. It is unlikely that hydrogen will be pushed heavily by the UK gov because of the expensive pipe rework. The reason they're pushing hard for heat pumps is because of the Glasgow Climate Pact; they're on the hook to reduce carbon emissions or pay heavy fines. To that extent, subsidising heat pumps becomes financially less unviable for them than doing nothing.

2. Regarding the heat in summer; the houses insulate well but don't do much to prevent heat coming in from the windows during summer. There are some pretty useful half-fixes; mvhrs+insulation, or recessed windows/overhangs/sunshades massively aid this. For those who rent that's not much help though :(