China says its kilometer-wide solar array could collect as much energy in a year as all the oil that can be extracted from Earth
In our Wild Ideas series, the Climate & Capital Media team explores emerging climate change innovation and solutions. Our Wild Ideas are not meant to distract from the critically important job of ending fossil fuel addiction and transitioning to clean energy — that’s non-negotiable. This features ideas, big and small, that could become pieces of the climate solutions puzzle. Some ideas will pan out and become important, others will fail. We hope exploring them will keep us all thinking about what’s possible. This week… space-based solar power.
The US, EU and Japan are all working to develop solar power in outer space. But China has unveiled a dramatic new plan to build a kilometer-wide solar array that it says could overcome solar’s limitations on Earth.
China says it plans to build its vast solar array in “geostationary orbit” about 36,000km above Earth. Space-Based Solar Power (SBSP) could utilize photovoltaic cells to collect the sun’s rays at ten times the efficiency of solar collectors on land. The energy harvested would then be transmitted by microwaves back to Earth.
In introducing the project, Long Lehao, senior scientist of the Chinese Academy of Engineering, compared it to the undertaking that was the country’s large-scale Three Gorges Dam. Built on the Yangtze River and spanning about 1.3 miles wide, the Three Gorges Dam is the world’s largest hydroelectric plant, and produces more energy than any other single power plant on earth.
Related content:
The Year of the Snake welcomes record clean energy use
$1.1 trillion investment opportunity in Asia’s energy transition
Foreign investors could stall coal plant closures in Asia
Scientists have been talking about space-based solar power for decades, but the concept was only considered feasible in the past few years due to new technology developments. Many major space-faring countries and companies have investigated the option, including the US, with NASA testing the feasibility for SBSP since the late 1970s. Japan is set to launch a small satellite this year to test the technology, and the UK Space Agency is watching the success of the Chinese tests closely.
China faces numerous obstacles in delivering its SBSP project, including how to launch a heavy lift rocket large enough to deliver the massive solar array into space, and developing a method to prevent major losses of energy to be transmitted by microwave through the atmosphere.
A rocket that could lift 150,000 kg to low Earth orbit and 54,000 kg to the moon is expected to be ready by 2033.
Whether or not we will see a paradigm shift in the future of renewable energy from land- to space-based solar power remains to be seen, but it seems China is ready to take on the challenge.
Featured photo: International Space Station solar array. Credit: NASA
