In the 1970s, the U.S. Department of Energy poured money into creating a miraculous technology: converting sunlight into electricity. Solar energy was a pipe dream, far too expensive and unreliable to be considered.
Solar power installations cost 80% less today than a decade ago. Alternative energy (like wind and solar) is now cheaper than conventional energy (like coal and gas). Last year, California generated 19% of its electricity from solar power, up from 1% just 10 years earlier. Solar-energy production worldwide has increased nearly 2,000% since 2009. Of approximately 100 gigawatts of solar generation added in 2018, China accounted for 44 and the U.S. 11.
Eliminating the carbon emitted in the production of electricity is crucial to keep the world from heating to dire levels. Innovation is not enough to avert the worst consequences of climate change, but there are solutions at hand that are cost-effective. Here are the things engineers have achieved, and the problems left to solve.
Today’s renewables: solar and wind The decline in the cost of solar and wind power over the past decade has transformed the energy industry. Wind capacity in the U.S. has doubled over the past 10 years and is expected to double again by 2030. Solar power is growing even faster, with total installed capacity expected to double by 2024. Together, the two technologies have helped renewables leap from 9% of the U.S.’s electricity generation in 2008 to about 17% in 2018.
Wind operators are using artificial intelligence and improved weather forecasts to position turbines for better performance, while solar-panel manufacturers are refining new materials and processes to generate more electricity from smaller panels and drive down costs.
The Grid: Interconnection and Storage In 2019, Nevada and Washington, California and Hawaii commited to 100% carbon-free electricity in the next generation. France, Sweden, Norway, Portugal and the U.K., among others, have set similar goals. However, solar and wind power have times when the sun doesn’t shine and the wind doesn’t blow.
One solution is to improve the ability to move energy from where it’s produced to where it’s consumed by building new power lines, known as interconnectors, that can move energy across long distances between regional power grids. Another is to store excess energy for later use—and this ability is expected to grow storage capacity tenfold by 2024. Engineers are developing novel alternatives that can store energy for longer periods of time.
Next-Generation Nuclear Nuclear reactors zero-carbon power representsy 20% of the U.S.’s electricity and 11% of the world’s. But safety and environmental concerns have increased the cost and complexity and construction has all but stopped. One strategy is to focus on smaller, simpler reactors that can be constructed in factories, produce less radioactive waste and require less day-to-day management.
Commonwealth Fusion Systems in Cambridge, Mass., is working to use new superconducting materials to build a fusion power plant—one that creates energy by combining atoms rather than dividing them, as in traditional nuclear. The project has the potential to revolutionize electricity.
Managing Carbon: Sequestration Limiting the increase in global temperatures requires eliminating the amount of carbon emitted into the atmosphere. Carbon capture and sequestration involves removing carbon from the atmosphere and either physically storing it, often underground, or leveraging natural processes that capture and store it, as trees do. But there is no economic benefit to storing carbon.
Any breakthrough in capturing carbon, reusing carbon or storing it at a large scale would mitigate the potential catastrophe of allowing it to continue to heat the atmosphere. Life could not only go on—it could go on more or less as it has.
Clean coal is a bit like wearing a porous condom – at least the intention was there