Taoism emphasizes locality. So if you have coal at your place and burn it, so be it. If you have no coal, use wood instead. Many people in the modern world, so far from nature, are unaware that the emissions from burning locally sourced wood for heat and cooking are actually very low... making it more attractive than other energy sources for these purposes, as long as you have some and a bit of time to collect, chop and maintain it. Transportation overheads are removed, fuel grows itself. Win. If you have no wood and no coal, be one with the natural cold :) http://nepacrossroads.com/fuel-comparison-calculator.php (Excepts transportation/purchasing overheads)