I'm fairly jealous of the electricity costs elsewhere in the world. I believe even the US has some decent rates compared to the UK. I'd probably throw a lot more at it if it wasn't so expensive. Even running 50TH's units costs a little bit each month.

If you stacked 6 nerdqaxe++'s you could be north of £100 a month with the consumption at the wall. They generally take around 90-100W at the wall at stock settings. Tuning them you might get a bit less. Hydro units seem to draw less power from my observation, which I assumed with the additional components wouldn't be true. Also, could be just lucky with those units I suppose.

I think 25-30THs might be the sweet spot for cost, contributing a tiny amount of power to the network to benefit it, but also be in it to win it.