For me, I have to get planning permission (which I'm not likely to get) to install a normal outside-fan/inside-unit air-conditioner. That's the downside of living in a conservation-area. The house is viewable on 3 sides from the road because of where it sits at the junction of 2 roads, and on the side that is private, we're actually very close to the road, so the noise of the fans running rules out that position.

The other route (and I looked into it) is to get inside-only a/c (which doesn't need planning permission because there's no outside unit) which uses water as the transport medium instead - so now I'm also using a constant trickle/stream of water from the mains, heating it up to ~45C and then letting it go down the drain. Cost of this ? About £30k

In all, for the few weeks of overly-warm weather per year, I'm better off getting portable a/c units that vent through a window. Or fans.

Still a nag screen. I go to my local library once a week and read all these titles for free...