Macadamia-nut shells will soon be the source of electricity for more than 1,200 Australian homes. Construction began this week on a biomass cogeneration plant in the northern Australian state of Queensland that will produce renewable energy by burning more than 5,000 tons of shells generated by the nation’s native macadamia nut industry. “This project … could be replicated across a range of other industries, including peanut, timber, meat, wheat, and grain processing, where waste streams could generate heat, electricity, and revenue,” said Kate Skilleter of Ergon Energy, the state-owned company behind the venture. The plant, the first of its kind in the world, should be online by August.