Following the relatively recent news that China and the US have agreed to stronger carbon-emissions goals, a Chinese entity by the name of Xiang Yang Institute and a US-based company called Focused Sun have announced that they are partnering to develop solar microgrids in China (and elsewhere).
The upside to solar microgrid use in the country is the potential there to cut down notably on coal use, and the associated carbon emissions — as well as adding local resiliency against grid outages, market fuel-costs, etc.
The Xiang Yang Institute’s Dean Jihong Chen commented on the partnership thusly: “Focused Sun has squeezed the cost out of solar concentrators, the key part of the microgrid system that focuses sunlight. Together with thermal storage and Chinese turbogenerators, we can produce small power plants for microgrids.”
Through the use of reflected solar energy, mineral oil can be easily (and relatively cheaply) heated to the 300°C temperatures that are needed for modern turbogenerators — this thermal storage can then hold the heat to be used at night, or the next day.
Speaking on this, the MIT Professor David Gordon Wilson commented: “The solar energy peak is at mid-day, but people need heat and electricity in the evening. For microgrids in the 100 kW to 10 MW range, low-cost solar concentrators and thermal storage combined with turbogenerators make more sense than photovoltaic collectors and battery storage. Thermal storage is the key missing ingredient.”
Worth noting is that roughly 4 times more solar energy can be captured via the Focused Sun concentrators (as per the company’s data) as compared to conventional photovoltaic panels of the same size. So, it is a notably more efficient process with regard to that parameter.
Also worth noting is that the system can apparently pay for itself in “as little as two years.” Not bad if true — but, of course, the rate of return on investment depends so much on specific circumstances, so that number may not relevant for most users.
Here’s a bit more information via Focused Sun:
At night or during cloudy periods, the energy is pumped from storage to the turbogenerator where 20% of the energy is converted to electricity. Another 50% of the sun’s energy is available as heat for example for warming homes, hotel rooms and greenhouses. The system produces both electricity and hot water. The Focused Sun concentrators are made locally bringing local jobs plus cheap, clean energy. For every dollar spent, four times more solar energy is captured.
As noted by the Director of the Solar Laboratory at Florida Atlantic University, Dr Amir Abtahi, this modular approach to design “that Focused Sun uses lets solar energy be customized to various power plant sizes.” Another plus.
Image Credit: Focused Sun