Internet Of Things / IoT / Connected Home / Smart Houses

I've been considering smart TRVs for that reason but I think it is probably cheaper just to turn off my central heating when I'm working from home alone and use a fan heater pointing at me.

In my mind smart central heating should save money rather than keep the entire house at a constant temperature.

In your case - presuming that you work in a room notionally labelled as study - you need a TRV in the study but if you use Tado you'll also need TRVs in your living area because otherwise when the study TRV requests heat you'll be heating your living area unnecessarily (this is my current situation because I'm waiting on an offer on TRVs).

I like Tado but it isn't quite smart enough for me - being asked to pay for the home/away assist grates (shakes fist) and schedules are all very well but our routine varies too much, so I reckon we're still paying to heat house we don't need to heat.

I'm planning on installing this to my Home Assistant to get free home/away assist:
https://github.com/sabsteef/Tado-home-away

But even then we'll end up heating rooms we aren't actually using. So I'm thinking about using Hue motion sensors to check someone is actually in a room, then if nobody has been in a room for a certain amount of time the Tado TRVs won't start heating it up, unless someone goes into the room for a little while (not quickly popping in), then they'll heat it for a bit before turning off again if they haven't detected movement.

I need to work out how to do this but it should all be doable in Home Assistant as the Hue motion sensors work well with it.

But that doesn’t achieve the goal of not heating the entire house while I’m working and only using one room from 9-5. In my mind smart central heating should save money rather than keep the entire house at a constant temperature.

This is why I use an electric air heater in the room in working, and the thermostat for the house applies outside of working hours... Though with Nest time to temperature meaning that it clicks on mid afternoon and slowly gets the house ready for the evening.

I bought one of these https://www.fenwick.co.uk/home-and-tech/home-appliances/fans-and-heaters/stream-heat-cooling-fan/2530020433895.html and it has a eco hearing mode which turns on full great below 18'c, mild heat below 20'c and turns off totally above that... This turns out to be perfect for my office space and the rest of the house is economical.