While I’m confident that South Australia’s and Tasmania’s feed-in tariffs are safe for now, if they were reduced to the low 8 cents a kilowatt-hour often seen in other states, the cost of solar electricity per kilowatt-hour would be 14.5 cents in Adelaide and 18.5 cents in Hobart.he Cost of Grid Electricity (Grid cents/kWh): Australians now pay an average of about 27.5 cents a kilowatt-hour for electricity, with considerable variation between regions. Determining what people actually pay in an area is difficult, as electricity retailers can be deliberately confusing.