RayGen edges closer to “solar hydro” success with new strategic partnerships

Australian “solar hydro” technology hopeful RayGen has announced a raft of new strategic partnerships, as the Melbourne-based company works towards its big-picture plans to develop a huge 100MW/1,000MWh solar plus storage project.

RayGen’s “dispatchable” concentrated solar and hydro storage technology is currently on track to be tested at a 50MWh-scale in Victoria’s north-west, backed by $3 million in funding from the Australian Renewable Energy Agency and a key partnership with major gen-tailer AGL Energy.

Last week, however, the company aired some of its much bigger plans – including aspirations to develop a 200MW solar plant with around 100MW/1000MWh storage – off the back a deal with Photon Energy.

As reported here, that deal will see Photon take an unspecified equity stake in RayGen (believed to be less than 10%) and act as project developer and EPC contractor for the projects it plans to roll out in Australia and elsewhere.

This week, another four “strategic partnerships” were announced between RayGen and a range of specialist technology suppliers, ahead of the company’s pilot project in Carwarp, Victoria.

The new partners include Atlas CopCo Power and Gas and Egesim Group, for the supply of Organic Rankine Cycle (ORC) systems; NIRAS Australia, for pit thermal energy storage solutions; KMI Jiangyin, for the supply of slew drives for the solar hydro technology; and Azur Space for high efficiency, multi-junction solar cells.

In a series of statements from each of the companies, RayGen CEO Richard Payne said the new partnerships would set the company up to pursue large-scale deployment of its PV Ultra and solar hydro systems.

On the PV Ultra side of the equation, Payne said the “extraordinary power density” of RayGen’s modules using Azur Space’s CPV cells would underpin a “new economic model for manufacturing and deploying solar power systems worldwide.”

As RayGen’s Will Mosley explains, the company’s PV Ultra technology (pictured above) does something that “no one else in the world” is currently doing, by using mirrors to concentrate sunlight onto super-efficient PV modules that are raised on a tower.

These specialist panels convert roughly 30 per cent of the sunlight directly into energy, while also capturing roughly 60 per cent of excess heat energy.

On the storage side, the heat energy captured by the panel from the concentrated sunlight is stored as hot (92°C) water in one reservoir, while the electricity generated by the panel (and not sent directly to the grid) is used to chill water to 2°C, which is stored in a cold reservoir.

“The difference in temperature of about 90°C has a similar energy storage capacity as pumped hydro with a height of 1000 metres – so really, really big pumped hydro,” Mosley says.

Between the two tanks is the Organic Rankine Cycle system – or heat to power turbine – where the hot and cold water boil then condense an organic working fluid to drive the turbine and deliver power to the grid whenever it is needed.

This is where Atlas Copco and Egesim come in, to deliver the Organic Rankine Cycle (ORC) engine of RayGen’s pilot plant.

“We are thrilled to announce our strategic alliance with Egesim and their partner Atlas Copco, two leaders of heat-to-power applications globally,” said Payne.

“With Egesim and Atlas Copco’s ORC solution, RayGen is able to deliver the economics of pumped hydro and the flexibility of batteries.”

NIRAS, meanwhile, is on board to develop the hot and cold reservoirs, or pit thermal energy storage solutions, for the project. The companies said the nominal size of each of these pits was 15,000m3, or about six Olympic swimming pools.

Jiangyin Kinematics Manufacturing, or KMI, will supply the slew drives for the project, a key component of the RayGen’s sun-tracking technology.

“KMI (Jiangyin) has known and worked with RayGen for 10 years and believe they are world leaders in the field,” said KMI managing director Ray Lin in a statement.

“Our strategic alliance allows us to supply of highly accurate and highly reliable slew drives for large scale deployment of RayGen’s PV Ultra systems.

“We believe that this technology can be competitive with coal power, matching the reliability and cost at large scale.”