Australia’s energy producers and utilities are calling on the government to support the existing natural gas-powered generation as a smooth market mechanism to move to growing shares of renewables in the electricity system. Australia has been closing coal-fired power generation and raising solar and wind power, but without enough baseload generation, it risks power shortfalls and blackouts, industry officials have warned. “If you're only supporting new renewables and you don't take care of existing gas assets, you run into trouble,”…