As solar power becomes more widespread, engineers and designers search for ways to more effectively use concentrated solar power. One solution? Heliostats. Originally found on giant solar farms, heliostats are mirrored devices that use a tracking device to follow the motion of the sun, which directs sunlight to a predetermined target.
When they’re used on solar farms, heliostats convert concentrated light to heat, which then drives a heat engine (usually a steam turbine) connected to an electrical power generator. Yet heliostats are proving increasingly useful in smaller applications, too, such as in commercial construction.
Consider One Central Park, a high-rise apartment and retail complex in Sydney, Australia, designed to include heliostats. A system of fixed and motorized mirrored panels capture sunlight and reflect it on the project’s landscaped terraces. At night, the heliostats become a work of art thanks to French lighting artist Yann Kersale, who created a colorful design that illuminates the towers.
Heliostats have a number of applications, which makes them increasingly enticing to developers.
“It has been suggested that small heliostats, placed on building rooftops, could be used like a solar power tower system, using the sun’s power to heat and cool a building or to provide input for thermal industrial processes such as processing food,” writes Justin McGar. “The system could also have the potential to be more reliable and cost-effective than a solar power tower plant, partly because it would not sacrifice 80 percent of the power collected in the process of converting it to electricity.”
Heliostats are already being used in areas such as the sun-deprived village of Viganella in the Italian Alps, the historic Reichstag building in Berlin, the Puente Hills Mall in California and the corporate headquarters of Genzyme Corp. in Cambridge, Mass., among other places — and we’ll likely see heliostats become even more widespread (with possible residential applications, too).
One major obstacle remains, however: Conventional heliostats are still expensive, which means engineers and designers face the challenge of finding commercially cost-effective designs that use fewer, lighter materials while also working as efficiently as traditional systems if they’re to become more commonplace.
Yet that dilemma isn’t unlike similar situations posed by other efficient, sustainable materials that were, at first, cost-prohibitive, and later became more accessible in response to market demand. We wouldn’t be surprised to see heliostats become much more commonplace in commercial (and residential) construction over the next few years. What about you?
Image via Design Build Source