Re using solar PV during daylight. At the moment, domestic users are encouraged to use make more use of their power needs at night and less during the day. The rationale is that this will mean less demand during the high demand daylight hours and enable a more steady 24 hour base load production, lessening the need for more power generating plants to be built just to cope with a high daytime demand (and excess production that is not used at night).
As the switchover to non-fossil fuel takes place, I'd expect the electricity network to become more flexible with less need for a high constant base load. So the situation might change in future years.
