The race to replace fossil fuels with clean alternatives has triggered an explosion in climate tech innovation and funding. That includes a heightened interest in fields that have plugged along for years — nuclear power, batteries and biofuels — as well as more obscure technologies that most people have never heard of.
We came across five ideas (below) that surprised us at last week’s Breakthrough Energy Summit in Seattle, where entrepreneurs shared their progress in developing and deploying new tech, and leaders in the space offered their thoughts for the future.
Breakthrough Energy Ventures (BEV), the VC arm of the Breakthrough organization created by Bill Gates, has raised more than $2 billion in capital since launching in 2015. BEV’s goal is to back companies across the economy with the potential to scale their innovations worldwide.
“By now we have over 100 investments,” said Eric Toone, a BEV investment committee partner, speaking at the summit.
“So are we done? Of course, we’re not,” Toone said. “We’re nowhere close to done.”
Toone introduced dozens of technologies at various stages of development, including some only starting to get attention as possible climate solutions.
He didn’t pitch any of the technologies as the next big investment for BEV, or suggest that they’ll be viable from a cost perspective. Instead, he emphasized how huge the challenge is to green every aspect of our incredibly energy-hungry economy and lifestyles. He suggested leaving no stone — ferrous iron oxide containing or otherwise — unturned in the pursuit of alternatives.
“We’re just at the very beginning,” Toone said. “Where there’s challenges, there’s opportunities. And there’s more opportunities here that I can possibly imagine. I’m incredibly excited about the future.”
Here are five of the lesser-known ideas:
Ocean current power
There are multiple ventures working on wave power, including some from the Pacific Northwest, as well as tidal power. Toone suggested a more obscure but massive source of marine energy: ocean current power. The amount of potential energy in ocean currents is 5 terawatts, Toone said. That’s about five times the energy generation capacity for the whole U.S.
“Just the Gulf Stream contains more energy than 21,000 Niagara Falls, more energy than 50 times all of the world’s rivers,” Toone said.
Ocean thermal energy conversion
The ocean has different temperatures, or thermal gradients, at different depths. It’s warmer at the surface, cooler deep underwater. Particularly in tropical areas, it’s possible to harness that temperature difference to generate electricity. The energy potential for ocean thermal energy conversion is a whopping 7 terawatts.
Ferrous iron oxide energy
There are meaningful efforts to boost geothermal energy production, which is already the top source of power for Iceland. But the Earth’s core has other power potential. That includes ferrous iron oxides that are found in abundant minerals. The iron can be used in oxidation-reduction chemical reactions with the possibility of capturing energy along the way.
Scientific research notes that the process, “would require the development of new technology, and certainly would be very costly. But the massive scale of the available resource perhaps justifies the effort.”
One of the challenges to rapidly deploying climate friendly technologies is the need to mine minerals used in batteries and other devices. A strategy for harvesting these materials in a more environmental way is to use biomining. Biomining employs microorganisms (bacteria) to extract and concentrate metals from rock ores or mine waste. There are hopes that biomining could be applied to other environments such as soil and the ocean and include plants to perform some of the work.
Atmospheric water harvesting
The planet is already experiencing freshwater shortages and that will only worsen with time. Desalination of saltwater is expensive but doable — so long as you’re near a water source.
The atmosphere, it turns out, contains seven times as much water as all of the Earth’s surface water, Toone said. It’s expensive to harvest, “but in many geographies, it may be the best alternative,” he said. “We need new approaches to atmospheric water harvesting that can generate large quantities of water at low costs.”