The $20 million Jemalong Solar Thermal Station near Forbes in western New South Wales has entered the commissioning phase and is close to reaching full operation, says developer Vast Solar.
The concentrated solar thermal power (CSP) plant is a pilot facility designed to prove the potential of Vast Solar’s low-cost, modular CSP technology, which uses molten salt as a thermal storage medium. The grid-connected pilot plant includes 3,500 heliostats and five receiver towers, as well as a 1.1 MW turbine that will deliver power to the grid.
Once complete, it will be Australia’s only operating, grid-connected CSP plant with thermal energy storage.
Vast Solar CTO James Fisher says the Jemalong pilot plant is 99 per cent constructed, but that because Vast Solar’s technology is still in the R&D phase it is difficult to put a time frame on the commissioning process.
“The pilot plant is essentially a full power station with all the complexities that go with delivering power to the grid, but at a small scale,” says Mr Fisher.
“It’s very likely that we will find a number of parts that don’t work as expected and require re-engineering, but if all goes smoothly I anticipate we should have the plant in full operation by May.”
This is a significant step in the development of Vast Solar’s CSP technology, which has been in development and testing for the past six years. Vast Solar’s system comprises multiple solar arrays, each with its own field of heliostats and its own thermal receiver. The thermal energy is used to heat liquid sodium to very high temperatures (~600C), which in turn is used to heat water to create steam in a boiler. This steam then drives a traditional steam turbine and generator which exports electricity to the grid.
The system stores energy as heat, which can be released as needed to provide stable, reliable solar power. The Jemalong plant will be equipped with three hours of thermal energy storage, but on a larger scale the thermal energy can be stored for days or even weeks.
“This is the final stage before we build our first commercial power plant,” says Mr Fisher.
“We have spent $20 million in developing, testing and refining our technology, but that is necessary before anyone will back a commercial plant costing in excess of $100 million. While I see many more years of R&D ahead, this pilot plant tests the technology that would be used in our first 30 MW scale commercial plant. It shows the full system from sun to grid and will be an excellent sales tool and R&D platform into the future.”
Mr Fisher says that, provided certain technical milestones are hit, the funding is in place for the commercial-scale 30 MW thermal power plant, which Vast Solar aims to commence by the end of 2016.
The completed 30 MW plant, also to be built in the Jemalong area, will have four hours of energy storage, approximately 90 solar array modules and 65,000 heliostats.