by LONDON – A California-based firm wants to launch a constellation of orbiting mirrors, which will direct sunlight to solar power plants to boost renewable electricity production after dark. A prototype light-reflecting satellite could make its way into orbit next year.
Ben Nowack, founder and CEO of Reflect Orbital, introduced the company’s plans at the International Space Energy Conference, held here last week.
Orbit shows constellation 57 small satellites orbiting the Earth in a sun-synchronous polar orbit formation, at an altitude of 370 miles (600 kilometers). In that orbit, the satellites would circle the planet from pole to pole as the planet revolved around them. The satellites would fly over every spot on World at the same time of day, making two passes per 24 hours. Together, the 57 satellites would provide the power plants with an additional 30 minutes of sunlight, at the time when energy is most needed, Nowack said.
“The problem is that solar energy is not available when we want it,” Nowack said at the conference. ” The more solar farms we build, the less people need it during the day. It would be great if we could get some solar energy before sunrise and after sunset, because then you could lower prices cut height and do a lot. And we think reflector technologies can solve this problem.”
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The cost of solar panels has fallen by 90% over the past 15 years, according to the International Renewable Energy Agency, and their efficiency continues to increase, thanks to advances in photovoltaic technology. Thanks to that, solar power is by far the cheapest form of electricity ever available to mankind Carbon Clip.
But the intermittent nature of solar energy generation is a problem that experts are still struggling to solve. On cloudy days, solar power plants are less productive than when the sky is clear. At night, solar energy generation stops completely. Battery systems and other renewable sources could make up some of that shortfall, but for now nuclear power plants and coal and gas are needed as back-ups.
“It’s very easy to replace the first 1% of the energy grid with renewable energy,” Nowack said. “It’s very difficult to replace the last 1%. That’s the energy you need on a day when it’s not windy but it’s raining.”
The Reflect Orbital satellites will weigh only 35 pounds (16 kilograms) each and will be equipped with 33-foot by 33-foot (9.9 by 9.9 meters) mylar mirrors that are deployed in orbit. Mylar is a plastic material used in space blankets, insulators and packaging. The mirrors are engineered to focus light into a tight beam that can be steered and focused based on the demand of solar farm operators.
“We want to make it as easy as possible — like, log into a website, tell us your GPS coordinates and we’ll get you sunshine after dark,” Nowack said.
He added that the mirrors are designed to prevent light pollution.
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“If you are around 10 kilometers [6 miles] from the edge of a solar farm site, you don’t see any light if you look straight up into the sky,” said Nowack. , if you look toward the solar farm.”
Last summer, Reflect Orbital tested its mirror on a hot air balloon that floated 1.7 miles (3 km) above the solar farm. The company was able to generate “500 watts of energy per square meter” (11 square feet) of solar panel, which is about “half the brightness of the sun,” according to Nowack. The company has secured funding to fly its first test satellite into space next year.
Other teams are studying orbital mirror concepts to boost solar power generation. For example, the University of Glasgow in Scotland is leading a European research project called SOLSPACE, which is also investigating the possibility of orbiting satellites equipped with thin reflective panels to direct sunlight towards large solar farms at the start and end of each day, when demand for electricity is highest.
Russia experimented with orbital mirrors in the 1990s with its Znamya project. The Znamya 2 mission was launched in 1992 and deployed a mirror in orbit that briefly flashed a beam of light towards Earth that crossed Europe from southern France to western Russia. The satellite fell back in The Earth’s Atmosphere after only a few hours.
There are orbiting mirrors, however, their opponents. Speaking at the conference in London, Andrew Williams of the European Southern Observatory warned that orbital reflectors, if not carefully designed, could shine brighter than the brightest stars and make the satellite worse. light pollution a problem already facing astronomers.
After the launch of the first few batches of SpaceX’s Constellation satellites in 2019, astronomers realized that these low-orbiting spacecraft could interfere with astronomical observations, leaving trails in images. SpaceXWilliams said, he has since managed to partially eliminate the problem by changing the surface of the satellites to reduce the amount of light they reflect.
