Tucson Electric Power (TEP), a south Arizona utility with 430,000 customers, has published its 15-year Integrated Resource Plan (IRP) in which it sets out its intention to abandon coal and have 70% of power generation come from renewables, supported by battery storage and gas plants. This transition will result in an 80% fall in emissions, and – in a desert state – big reduction in the use of surface water and groundwater. The utility now plans to see the last coal generation in 2033 at the latest. SGS Units 1 and 2, coal generators with a capacity of 387 MW and 406 MW respectively, are central to the utility’s present energy output, but under the IRP, the introduction of mass…