Sparks

New energy devices

 By RP Siegel

Several new energy systems have recently emerged that provide the dual function of capturing carbon and producing energy at the same time. Researchers at Cornell University have developed a oxygen-assisted aluminum/carbon dioxide power cell that uses electrochemical reactions to both sequester carbon dioxide and produce electricity…

(Cover photo by www.breakingenergy.com)

Isn’t there some way that we can pull carbon back out of the atmosphere? That would certainly help our efforts to slow climate change. It turns out there are several technologies that can produce negative carbon emissions. They are relatively new, and not yet achieving significant scale. Still, it’s a promising trend that deserves attention. Trees, of course, already do this. Here are some manmade ways, that don’t necessarily require significant amounts of open space.

Some products use carbon dioxide as a raw material, effectively locking that carbon into solid forms, at least until they are left to decompose in the future. Even postponing carbon emissions by a few decades can be helpful.

Inventor Marcel Botha came up with an idea for “a shoe without a footprint.” His idea was to capture CO2 and use it to produce foam that could be used in an athletic shoe. The idea was underwritten by NRG Energy who helped to produce some prototypes to promote their Carbon XPrize, a four-year competition seeking ways to “turn carbon emissions into something useful.” The winning entry will receive $20 million to develop their product.

Cornell Electrochemical cell

The idea of using CO2 to produce foam is not completely new. Bayer Materials Science, now known as Covestro, has been working on a process for years to produce polyurethane foam from waste CO2 gas. Polyurethane foam is widely used, not only in sneakers, but in mattresses as well as spray insulation for buildings. The process converts CO2 to polyol, which is a building block in the production of polyurethane. The company has built a plant in Leverkusen, Germany, to produce 5,000 metric tons annually. The final product reduces CO2 by 15-20 percent, by eliminating the need for propylene oxide feedstock. Michele Aresta, a chemist at the University of Bari in Italy, assessed the opportunity, saying products “could directly use some 300 million metric tons of CO2 per year, while indirectly reducing emissions by around a gigatonne per year.”

Lynden Archer, a researcher at Cornell University has developed a technology that captures carbon while producing electricity at the same time. The device is an electrochemical cell that uses aluminum as the anode, and a mixed stream of carbon dioxide and oxygen as the cathode. The cell produces 13-ampere hours per gram of carbon, while also converting the reactants into carbon-oxalate, a useful material commonly used in the production of pharmaceutical, fiber and in metal smelting.

SEE MORE: The carbon climate solution by Michelle Leslie

UN-experts-urge-carbon-restrictions

But a similar, three-for-one accomplishment has been achieved by Fuel Cell Energy, a company that finds creative ways to utilize its molten carbonate fuel cell technology to create multiple value streams. Last year, the company developed a novel configuration designed to be used in conjunction with conventional power plants. The cell is fed exhaust gas. It then concentrates CO2 in a side reaction, while producing additional electricity at the same time. They have recently partnered with Exxon-Mobil to utilize this technology in natural gas-fired power plants. They have also have developed systems for wastewater treatment that utilize biogas to produce electricity and heat, while at the same time producing clean hydrogen as a byproduct.

Finally, Climeworks makes a product called the Collector, a machine that draws in air from its surroundings and extracts carbon dioxide. Each unit can extract 135 kilograms per day. The machine has a modular design that enables multiple units to be configured into an array. The process utilizes a sorbent material to capture the CO2 and low-grade heat to release it.

about the author
RP Siegel
Skilled writer. Technology, sustainability, engineering, energy, renewables, solar, wind, poverty, water, food. Studied both English Lit.and Engineering at university level. Inventor.