If you know what concentrated solar power plants are at all, you’re probably picturing a massive falice in the desert surrounded by a circular harem of mirrors. That’s not the kind of thing you could plunk down in your back yard for round-the-clock solar power – even if you could afford it.
But a group of South African researchers have announced a breakthrough on the road to “plonkable” CSP. The Solar Thermal Research Group at Stellenbosch University, headed by Paul Gouche, is experimenting with a new technology that makes CSP infinitely more accessible and, in the long term, more affordable.
“We are developing plonkable heliostats,” Gouche told The Guardian. “Plonkable means that from the factory to installation you can just drop them down on the ground and they work.”
Concentrated solar power works with mirrors that focus the sun’s heat onto the top of a central cylinder where circulating water or molten material is rapidly heated. It retains that heat as it circulates and generates electricity from the heat. That means CSP is energy production and storage in one.
Molten materials that can retain the sun’s heat for up to 12 hours can be used to generate electricity through the night after the sun has set. It’s the perfect answer to the riddle of how to combat grid instability as variable renewable energy sources take over for on-demand coal and natural gas power. But it has been far too expensive and cumbersome and has lost increasing ground to solar photovoltaic technology as those panels have become more and more affordable in recent years.
Gouche’s team might have solved for the cumbersome and expensive hurdles.
The team’s Helio 100 is a pilot project demonstrating an array of more than 100 heliostats measuring no more than 23 square feet each.
“Every part in it is manufacturable and installable by two sets of hands, or one rugby play as we found out,” Gouche told the Guardian.
The array generates 150 kilowatts of electricity, which is enough to power about 10 homes. In its current iteration, it’s already cheaper than diesel generators would be. But this is just the beginning. As the research progresses, “plonkable” CSP could be a major game changer for rooftop solar around the world and for the way we consume energy and the way power companies provide it.