Sustainable? Yes, in theory, but no in practise. That's my gut feeling because I doubt that wood (or lignin producers) will grow as fast as our travel (and heat

Sustainable? Yes, in theory, but no in practise. That's my gut feeling because I doubt that wood (or lignin producers) will grow as fast as our travel (and heating) will use them up. Just skimmed some studies (in German) describing these consequences. And here in Europe there's currently the "trend" to switch from gas heating to pellets (or just wood stoves in private buildings) duento the "energy crisis" which results from the war in Ukraine (and missing or failed long term strategies in politics earlier) . But calculations show that this would kill our forests fast, because of over consumption, again. And, last but not least, studies show that wood stoves produce "second hand smoke 2.0" which isn't healthy either. So just changing fuels from dead dinosaurs to dead trees won't help us in the long range, I expect.