The thought of beaming solar energy down from space might sound like science fiction, however it’s being taken seriously by a growing variety of governments. A brand new evaluation shows it could significantly lower the price of Europe’s 2050 net zero commitment.
Space-based solar energy was first conceived in 1968 but largely remained on the fringes of energy policy discussions. Nevertheless, as countries all over the world committed to rapidly reducing greenhouse gas emissions, the concept began to realize traction.
Space agencies within the US, Europe, Japan, and China are actually actively developing and testing space-based solar energy concepts. However the technology remains to be nascent and very expensive, which raises serious questions on whether it could truly contribute to net zero goals.
A brand new evaluation in Joule takes a stab at predicting whether the technology could play a task within the energy transition, based on current projections. The researchers found that two designs currently under development at NASA could potentially help. They may, in response to the paper, even reduce the price of achieving a carbon-free grid in Europe by 2050 by 7 to fifteen percent.
“That is the primary paper to place space-based solar energy into the energy system transition framework,” senior creator Wei He, at King’s College London, said in a press release. “We’re currently at a stage to transfer this blue-sky idea into testing at a big scale, and to start discussing regulation and policymaking.”
The European Union has committed to reducing overall carbon emissions to net zero by 2050, which might mean replacing just about all fossil fuel energy production with low-carbon sources comparable to wind, solar, and nuclear power.
This may require significant changes to the grid, most notably massive increases in energy storage capability to address the intermittent nature of renewables. Space-based solar could potentially simplify things, since it would supply power across the clock.
“In space, you potentially have the flexibility to position solar panels to at all times face the sun, which suggests power generation may be nearly continuous in comparison with the each day pattern on Earth,” says He. “And, since it’s in space, the solar radiation is higher than on the Earth’s surface.”
The brand new study considered two designs currently under development at NASA which might be at various levels of sophistication and technological readiness. The primary, referred to as a planar array, is actually a big satellite with solar panels on one side and equipment to beam power right down to Earth in the shape of microwaves on the opposite. The second is a more advanced design referred to as a heliostat swarm. This approach contains a group of steerable reflectors that redirect sunlight to a central collector that then beams it right down to Earth.
The primary design is significantly more mature, the authors note, and so could likely be deployed sooner. Nevertheless, since the transmitting face has to point towards the Earth it may well’t at all times maintain the perfect angle for collecting sunlight. That signifies that over the course of a 12 months, it’s only in a position to generate power 60 percent of the time.
In contrast, the heliostat can move its mirrors to keep up optimal sunlight collection at nearly all times. However the design is way farther from real-world realization, the authors write, and constructing it could require huge advances in our ability to autonomously construct arrays in orbit using robots.
Nevertheless, despite their embryonic states of development, NASA has forecasts for the way much each of those technologies is prone to cost out to 2050. The researchers compared these projections against forecasts for renewable energy costs over similar time frames.
They found that space-based solar would grow to be commercially viable if costs dropped below 14 times the projected 2050 cost for solar energy. If costs dropped below 9 times that quantity it could potentially provide just about all of Europe’s required power. It’s because, despite the still-high price tag, these satellites could beam power anywhere on the continent almost across the clock, translating to big savings on transmission and energy storage infrastructure.
Based on NASA’s cost projections, the researchers found that the heliostat design could reduce total energy system costs by 7 to fifteen percent by 2050, replace as much as 80 percent of Earth-bound wind and solar installations, and reduce battery usage by over 70 percent. Some long-term hydrogen storage should still be required to tide the continent over through the winter months though.
The planar design wouldn’t be economical, however the researchers said its higher maturity level means it should still be pursued as a technology demonstrator that might help prove out the concept.
The authors note that regulatory challenges and public acceptance may present significant hurdles. Satellites that beam high-power microwaves right down to Earth include considerable safety concerns and the receiver stations may have to be enormous—on the order of several square kilometers.
Still, this study is considered one of the primary to offer a concrete evaluation of the technology’s potential to assist fight climate change. And given the size of the challenge we currently face, we could do with as many options as possible.