One time Liberal party leader John Hewson (now chairman of a company called SolarStor) made a splash in the media today with an announcement of solar thermal power plant in Port Augusta in South Australia.

Renew Economy has the details - Hewson’s Solastor promises world’s cheapest 24/7 solar power.

The 170MW, $1.2 billion project was officially launched in Adelaide on Tuesday by Hewson, who said he was confident the technology could produce the lowest-price 24/7 solar power in the world.

According to Solastor, this is “the ideal technology” to replace the almost 20,000 megawatts of coal-fired power plants “that will inevitably be phased out over the next 10 to 20 years,” as well as diesel generation systems such as those used in remote communities, islands and mine sites. In Australia alone, the company says, there could be a market for 400 Solastor plants.

The costs being quoted are so low that even RE's Giles Parkinson is being a little wary, sounding some notes of caution - Hewson’s enthusiasm for solar towers is welcome, but wild claims are not.

The proposed plant will use graphite rather than molten salt for heat storage - apparently they licenced the Lloyd Energy Systems / Larkden technology for this (according to a SolarStor web page now only available through Google cache).

Australia isn't the only country with new CSP plants being planned - RE also has an article about project announcement in Dubai - Dubai plans world’s biggest, and cheapest, solar tower + storage project.

While South Australia is leading the way in adopting renewable energy in Australia (recently passing the 50 per cent renewable energy mark), not everyone wants the state's future to be solar powered.

ReNew Economy reports that there are proposals to build a gas fired power plant with the fuel coming from coal gasification in the recently closed Leigh Creek brown coal mine (ignoring the dismal history of this process elsewhere in the country) - Not dead yet: Miners want to “gasify” closed brown coal mine in SA.

While Port Augusta waits to see if any solar thermal power plants will be constructed in the town, one project which has gone ahead is a smaller solar tower providing electricity, heat and desalinated water to a tomato farm.

The company behind the project is Aalborg CSP. The project consists of a tower with a 234-tonne central boiler and 23,000 mirrors.

The "Integrated Energy System" will be the first large-scale CSP-based technology in the world to provide multiple energy streams – heating, fresh water and electricity – for horticultural activities.

Port Augusta's ageing coal mines and coal fired power plants have been destined for closure for some time, with the clock finally winding down on them and the remaining Northern Power plant scheduled to close down in May.

There have been various proposals to build alternative solar power based generation facilities in the region as a replacement, leveraging some of the existing infrastructure, however most of these have been abandoned.

Now that new Prime Minister Malcolm Turnbull has decided to keep the Clean Energy Finance Corporation alive (dumping plans by his incompetent predecessor to shut it down), a new push has begun to build a solar thermal power plant in the Port Augusta area.

The latest plan is for US company SolarReserve to build a 110MW solar tower plant, similar to the Crescent Dunes facility in Nevada.