Recommendation for solar (or powered?) roof vent models?

[PhilT]

I merged the ask into the topic @mark_m referenced, and a related one previously linked by @grahroll (Aug 2021)

Whirlybirds vs Solar Whirlybirds vs Power Exhausts

There are two or three topics on insulation; this is not about insulation although related, so I am starting a new topic. Has anyone upgraded or installed solar whirlybirds or mains powered exhausts, and what have been your experiences? There are lots of references to whirlybirds but not many to solar or mains powered ones beyond ads and the odd whirlpool discussion. I found one ‘throw away’ reference on the community but not so many details were included. My 2 whirlybird house in NE Melbo…