Around the world, entrepreneurs are trying to turn green tech ideas into viable businesses. Many are working with technology that has been proven to work, but is too expensive for widespread use. The challenge is finding ways to bring the costs down enough so that their solutions can be scaled up to effect real change.
Here is a collection of innovative companies and inventors who believe they are close to hitting that mark with products ranging from the world’s whitest paint to high-efficiency electric batteries made from one of the most plentiful elements on Earth.
1. Earth-Cooling Paint
In 2020, a team of graduate students led by Purdue University mechanical engineering professor Xiulin Ruan came up with a formula for what Guinness World Records later recognized as the world’s whitest paint. While it looks pretty similar to other white paints, the new ultra-white reflects up to 98.1 percent of sunlight, which means unlike most paints, which warm buildings, this one can cool them down.
According to a Purdue study published in the Journal of the American Chemical Society, the new paint can lower surface temperatures 8 degrees Fahrenheit by day and 19 degrees by night. Less heat means lower energy usage and lower greenhouse gas emissions. A compound called barium sulfate is what makes the paint so reflective. Different sized particles of the chemical scatter different wavelengths of light. The Purdue team used particles of many various sizes to reflect as much light as possible.
“Products like this ultra-white paint have the potential to make a real difference,” says Karema Seliem, associate director of LEED technical development at the U.S. Green Building Council.
While Purdue’s Ruan says the paint was originally intended as a roof coating, he’s been approached by companies in industries ranging from textiles to spacecraft. A new iteration of the paint, developed last year using a different reflective chemical, is lighter and thinner than the original (although slightly less reflective), which could make it a practical coating for cars, trains and airplanes.
According to a Purdue spokesperson, Ruan and his team have partnered with an unnamed company to manufacture super-reflective paint commercially. The spokesperson, however, declined to say when it might hit the market.
2. Taking Carbon Out of the Air
Direct air capture (DAC) is a green technology whose time hasn’t quite come, but it seems to be getting closer.
Chemical filters in DAC units trap CO2 out of the air. The captured CO2 can be used to make eco-friendly products like fertilizer or fuel, or it can be pumped underground, where it is trapped permanently in rock. While the technology is proven, it now costs between $600 to $1,000 to get a metric ton of carbon out of the air via DAC, and green tech experts think a large market for the process won’t spring up until somebody gets the price under $100. Several companies around the world are competing to be first.
Arguably, the leader in that race is a Swiss company called Climeworks, whose approach mixes trapped CO2 with water and pumps it underground. The company has attracted big name investors and clients, including the band Coldplay, which hired Climeworks to take an amount of CO2 out of the air equal to what the band’s current world tour is generating.
Climeworks’ strategy has been to sign up customers willing to bankroll its efforts to get near the magic $100 mark. Earlier this year, the company said its Orca plant near Reykjavik, Iceland, which can extract 4,000 tons of carbon, had become the first in the world to achieve “large-scale capture” of CO2. The work was done for Microsoft, Stripe and Spotify. Climeworks didn’t say how much CO2 it had captured or at what price, citing confidentially agreements with its customers, but DNV, a risk management and certification company, said it had independently confirmed the company’s claim.
At a conference this year, Climeworks co-founder Jan Wurzbacher, who has expressed confidence his company can get the price down to $200, wasn’t specific about the current total cost, except to say that it was less than $1,000 per ton.
Meanwhile, the company is pressing ahead. In June, Climeworks announced a second Icelandic facility, Mammoth, slated to open early next year, that will have the ability to capture 36,000 tons of CO2. Co-founder Christoph Gebald says the company’s new goal is global expansion, beginning with a project in Kenya. “As we look toward 2024, we remain committed to making a climate impact at scale with our necessary DAC technology.”
3. A Very Old Technology, Repurposed
When biomass—agricultural waste like plant husks, stalks and wood—are burned, or even when they simply decompose, they release CO2 and other climate-changing gases like methane and nitrous oxide into the atmosphere. But if biomass are heated without oxygen, those substances are trapped in a black ashy substance called biochar.
Farmers have known for thousands of years that biochar makes good fertilizer. More recently, scientists and entrepreneurs have gotten excited about it as a way to keep CO2 out of the atmosphere. In addition to fertilizer, biochar has a range of commercial uses, including as animal feed, a source of alternative fuel and an additive to concrete.
Biochar manufacturing company Biochar Now, for instance, uses a “slow pyrolysis” kiln technology at its Colorado plant to make biochar, which it packages in different sizes—from particle to chip, depending on intended use—and sells. “We created a patented technology that is easily scalable,” says Biochar Now founder and CEO James Gaspard. Biochar’s massive kilns, he says, can produce biochar at industrial scale.
Biochar Now is currently partnering with corporations across industries and with government; last December, Boulder County gave Biochar Now a $100,000 grant to take portable biochar kilns to remote parts of the country where there are large amounts of waste wood, among them wildfire sites. The waste wood will be turned into biochar to be sold to farmers, keeping it out of landfills where it would generate methane.
4. Shopping Bags Made of Seaweed
Almost all plastics are made from fossil fuels, so manufacturing them contributes to climate change. And once plastic objects have been used and discarded, they sit around the environment virtually forever. According to the nonprofit Plastic Oceans International, 50 percent of all plastic produced is for single-use purposes. The Ellen MacArthur Foundation, which promotes a “circular economy,” in which things are recycled rather than trashed, says there will be more plastic in our oceans than fish by 2050.
For years, entrepreneurs have been trying to come up with commercially viable, environmentally friendly alternatives to plastics but with only limited success. Corn-based plastics, for instance, are land-intensive and difficult to compost. Other alternatives are expensive to manufacture.
Sway, a small Bay Area-based startup, sees an opportunity in seaweed—a plant that doesn’t take up land or use fertilizer and naturally removes a significant amount of CO2 from the atmosphere. The company extracts the naturally occurring cellulose from seaweed and turns it into a substance with the lightness, strength and flexibility of plastic. Sway says this can be used in existing plastics manufacturing equipment and biodegrades quickly. At commercial volumes, the company says, its seaweed materials are only marginally more expensive than traditional, petroleum-based packaging.
Sway’s first project was a plastic substitute that can be used in shopping bags and the thin wrapping used in the packaging that comes with online clothing orders. This year, the company was named a winner of the Tom Ford Plastic Innovation Prize, a global competition that awards creators of scalable, biologically degradable alternatives to plastic polybags a $1.2 million cash prize. The money is split among three winners, with Sway receiving the majority. Among the categories judged were cost, performance, scale and social impact. Sway CEO and co-founder Julia Marsh says the recognition “proved that mainstream brands are hungrily seeking solutions that replenish the planet.”
Since then, Sway has entered into partnerships with home and lifestyle goods retailer Graf Lantz and footwear brand Ales Grey. Marsh says the company is now scaling up production to commercialize wrappers and pouches for food and beauty. “We see the massive demand for Sway seaweed packaging as an opportunity to help promote regenerative practices, interlinking our success with the health of oceans, communities, and land,” she says.
5. Rust-Powered Batteries
One of the biggest challenges to reducing the use of fossil fuels with renewable resources like solar and wind is how to store the energy they produce for long periods of time. What do you do for electricity on days when the sun isn’t shining, and the wind isn’t blowing? Lithium-ion batteries like those in cell phones and electric cars are expensive to make, not good at storing energy for a long time—and sometimes they explode.
“Recent severe weather events, ranging from heatwaves to cold snaps to thousand-year rains, have highlighted the weakness of our electric grid,” says Mateo Jaramillo, co-founder and CEO of a Somerville, Massachusetts, startup called Form Energy. “We need new, transformative energy storage technologies capable of cost-effectively storing electricity for multiple days.”
Form’s solution: batteries that store energy using iron and air. When iron and air combine, they form rust, a process that releases energy. Apply an electric current to rust and it turns back into iron, trapping energy. Form’s batteries are charged by this “reverse rusting.” They discharge when air is pumped in: the iron turns to rust and the stored energy is released.
The idea of iron batteries isn’t new, but they’ve never been practical for small devices or vehicles because they are so heavy. Weight would be much less of an issue, though, for large and permanent iron battery facilities meant for storing large amounts of energy from a power plant. And iron, unlike lithium, is cheap, plentiful and non-explosive.
Form says its technology can store energy much longer than existing technology—up to 100 hours—and can bring the price of storing electricity down from the current $50 to $80 per kilowatt, to less than $20. Jaramillo says that’s because these batteries rely only on abundant, safe, low-cost materials that can be fully sourced in North America.
With $760 million from investors, Form is building a manufacturing facility in West Virginia that’s set to begin operating in mid-to-late 2024. Jaramillo says Form’s goals are “enhancing grid resilience and security, increasing grid reliability and safety, creating good-paying jobs and economically benefiting local communities and ensuring the inventions that secure our energy future are built right here in the United States.”