Photon Energy, a renewable energy developer based in the Netherlands, announced on November 3 that it has acquired 1,200ha of land in Australia to build a utility-scale solar-plus-storage project. The project, which is located in the state of South Australia, will feature a new kind of concentrated solar thermal array as well as a new kind of thermal energy storage system. The project will have a generation capacity of 300MW and a storage capacity of 3.6GWh.
The generation and storage technologies deployed at the project will be provided by Australia-based RayGen. “PV Ultra”, which is the proprietary generation technology developed by RayGen, integrates concentrated solar power with photovoltaics. In terms of operation, an array of mirrors directs the sunlight onto a receiver that contains PV Ultra modules. These modules cogenerate electricity and heat from the focused sunlight. The company’s official website states that a PV Ultra module outputs as much as 750kW per square meter, whereas a conventional c-Si module outputs around 0.18kW per square meter.
Turning to energy storage, RayGen offers “Thermal Hydro” that comprises a hot reservoir and a cold reservoir. The temperatures of the two reservoirs are maintained by the heat and electricity from PV Ultra, and they work together to store energy as a temperature difference. Hence, this system differs from pumped hydroelectric energy storage that relies on the gravitational potential energy of water. The heat from the hot reservoir can be used to drive a steam turbine, while the temperature difference created with the cold reservoir can generate electricity through an Organic Rankin Cycle engine. The roundtrip efficiency rates of most electric-thermal energy storage systems are less than 50%. By contrast, Thermal Hydro offers a roundtrip efficiency rate of more than 70%.
Photon Energy has been involved in the development and O&M of PV projects in Europe and Australia. It formed a strategic partnership with RayGen in April 2020. With RayGen’s technologies, Photon Energy is able to offer integrated renewable solutions that can operate 24/7 and offer a huge potential for scaling up.
A 1MW project for demonstrating RayGen’s unique technologies was set up in the state of Victoria six years ago and is still in operation. Photon Energy intends to continue deploying Ultra PV and Thermal Hydro for many project sites. RayGen in its press release about the project in South Australia also stated that it raised AUD 55 million in its Series C funding round. Investors in this round include Photon Energy, AGL Energy, Schlumberger New Energy, Chevron Technology Ventures, and Equinor Ventures.
RayGen also said that it is currently building another solar-plus-storage project in Victoria. With a generation capacity of 4MW and a storage capacity of 50MWh, the project is expected to enter operation in the middle of next year. The total investment in the project is AUD 30 million, half of which is coming from the Australian Renewable Energy Agency.
Photon Energy said that the preliminary design of the project in South Australia calls for a generation capacity of 300MW, of which 150MW will be connected to the grid. The company further pointed out that the 3.6GWh storage component will provide enough power to meet 24 hours of full load, even though RayGen’s previous press releases said Thermal Hydro offers 10-17 hours of discharge. Both Photon Energy and RayGen claim that the project in South Australia sets the record for the largest energy storage capacity of any type except pumped hydro. Looking at the development schedule, Photon Energy is currently proceeding with permitting and grid-connection application. The company hopes that the project will be ready to build by the end of 2023.