Heat pump != Geothermal energy generation, or any energy generation at that

Home geothermal /could/ be a power source, sure, but I do not believe that’s what OP intended to say when mentioning heat pumps. I’d be pretty surprised if it was becoming common in Europe to have home geothermal

A heat pump (which are more common in Europe, but they’re gaining popularity in the US) is essentially a reversible air conditioner that can take advantage of the latent energy in the air to move heat very efficiently. They’re a great invention, but they have nothing to do with producing energy