A Kerman business is reusing cow manure to create electricity and hydrogen. California calls the venture ‘groundbreaking,’ but environmentalists worry credits that prop up the biogas industry end up harming communities.By Steven RodasKERMAN, Calif.—One hundred degrees on a steamy Thursday afternoon and not much can be seen along the dust-blown avenue in Kerman. A school bus cruises by. Cows lap up water or feed behind a fence. A tractor crosses the road.