> seem more like a budgetary and political issue than an engineering challenge.

Science is about proving that something can be done at all.

Engineering is about taking that result and productionising it - doing it reliably, safely, effectively and on a budget. On the right site, even if that's in a busy city. "time and budget issues" are part of any engineering challenge. Very few engineering projects are "Money no object".

An also, there currently isn't the political will in the UK to invest in expensive infrastructure and engineering projects. London actually gets more investment than the hinterlands. See https://www.reuters.com/world/uk/whats-happening-hs2-britain...

It seems like we're in agreement here? Geothermal heat pumps aren't particularly novel, so it doesn't seem like engineering a solution is the blocker here. It's mainly politics.

Exactly, budget is an engineering concern, and in this case it's nigh impossible to engineer a solution, given the space and budgetary constraints.

The budgetary constraints are purely political though. Stuff like this has been engineered before at a reasonable cost (eg the Green Park station for 9M according to a poster above). So while yes things have to be engineered to a cost, it’s clearly not some impossibility high number.