The latest South West Interconnected System (SWIS) Demand Assessment describing the future of the Western Australia power grid was published yesterday. In its “Extreme Growth” scenario there will be 500 TWh of annual demand come 2042 (equivalent to 57 GW running constantly), in a state with a population of just 2.6 million people. Even in the High Growth scenario, which doesn’t maximize every possible load source, there will be 150 TWh of demand, most of it coming from hydrogen and mining. The report, written by Energy Policy WA on a fast-tracked basis since August, states that 4,000 kilometers of new transmission lines (all internal, with some running inland to mining interests) are needed – the government has just committed $85…