Basically, my question is pretty much what the subject line says. Is there any way to have steam power using eco-friendly resources? My setting is a fantasy world with a modern-ish society partially influenced by Ancient Rome, but with steampunk-style technology (combined with low-key magic).
I've searched Google and Wikipedia for "ecological steam power" and "steam power". Unfortunately, my knowledge about this sort of thing is quite limited, so I haven't been able to draw any sensible conclusions myself.