A gas-based design seems like it would be better at a small scale - e.g. the facility in the link has a reservoir the better part of a mile away from the turbines, and has a max output of 600 MW or so.
CO2 may actually be a good working fluid for the purpose - cheap, non-toxic except for suffocation hazard, and liquid at room temperature at semi-reasonable pressures. I'm not an expert on that sort of thing, though.
A gas-based design seems like it would be better at a small scale - e.g. the facility in the link has a reservoir the better part of a mile away from the turbines, and has a max output of 600 MW or so.
CO2 may actually be a good working fluid for the purpose - cheap, non-toxic except for suffocation hazard, and liquid at room temperature at semi-reasonable pressures. I'm not an expert on that sort of thing, though.