Surelly using the rotational energy of corpses turning in their graves at what’s done in their name/by their family/just done somewhere, would be easier.
For one, they’re way easier to procure than vampires plus the raw material requirements are lower (in some cases merelly saying certain things is enough to induce rotation).
There are some downsides, however, such as how they have to be in graves for it to actually work (so it’s probably a method best used for bulk generation using existing graveyards, plus there are some engineering challenges in connecting the actual corpses in situ to the turbines for energy generation, which are not present in a system made from the ground up for energy generation such as the vampire piston) and, of course, as the corpses age and decompose they become more brittle and it’s easier to get catastrophical failure if the turbine offers too much resistance, which means energy production decreases over time or, to avoid turbine replacement later, from the get go a less powerful turbine has to be connected to a pristine condition corpse.