Sydney Morning Herald: WHEN Sydneysiders flick on the power, there’s every chance some of the electricity has come from a couple of coal-guzzling power plants in the Hunter Valley. Eraring power station’s 200-metre-high chimneys tower over Lake Macquarie, while further west, the Bayswater station is set against beef and dairy country near Muswellbrook. Drawing on the region’s vast coal fields, these state-government owned giants share the title of biggest stations in the country, and supply about …