I have my own server room and I was recently asked by another member on here if I could host some of his machines, but the problem as you have found is that the UK is not a good location to do this.

Although I have decent rates due to volume of 10p kwh, by the time you add the VAT and climate change levy it's up to around 13p kwh which is the equivalent to $0.20 in the USA

Once you have added on some for cooling, maintenance and profit the rates are just too high to be worth doing.

Another problem is the stinking 20% import duty + fees we have to pay when something is imported.

Because of this I am slowly selling off my old equipment and having my new stuff shipped to the USA to be hosted there. Because they have such low electric rates they can offer the full service for what I pay on just electic plus no taxes.

I wish you well if you move forward, but I don't see much of a demand here.