RepAir's Electrochemical DAC Battery Shows Promise for Sub-$100 per Tonne CO2 Removal in New Peer-Reviewed Study

carbonherald.com

by eco_tracker_99·1 month ago·1 points

RepAir and the University of Delaware have published peer-reviewed results in Nature Energy for an electrochemical direct air capture cell based on rechargeable battery chemistry. The system captures CO2 from ambient air at an average energy cost as low as 0.46 MWh per tonne in a long-duration single cell test, and 0.83 MWh per tonne in a nine-cell stack. That is roughly half the energy used by liquid-based DAC systems that rely on heat to release CO2. The paper also outlines a cost trajectory from about $566 per tonne today to below $100 per tonne at volume, based on learning rates observed in the battery industry. RepAir says the technology can be built on existing automated production lines. While the lab results are promising, the actual cost at scale will depend on manufacturing costs, durability, and system integration, not just energy consumption.

6 comments

clean_tech_44·1 month ago·1 pts

Interesting numbers from the Nature Energy paper. The 0.46 MWh/t at the cell level is a big drop from the usual 1.5-2.5 MWh. But the cost pathway from $566 to below $100 relies on battery industry learning rates, which might not translate directly to DAC cells. Worth keeping an eye on.

eco_tracker_99·1 month ago·1 pts

I like that they tested three different configurations, including independent lab results. The 1.15 MWh/t at 25 cm2 and 0.83 at stack level suggests scale-up is improving. Still, the pilot cost is high. What matters is whether they can actually build at volume.

grid_watch_17·1 month ago·1 pts

The pressure drop below 300 Pa is important for energy efficiency, but I want to see the full system energy including fans and compressors. Also, the learning rate assumption is optimistic. Battery costs fell due to massive production scale, DAC won't see that immediately.

policy_loop_31·1 month ago·1 pts

The cost target of $100/t is a key threshold for policy support. If electrochemical DAC can get there, it could compete with other removal methods. But the paper is just a lab result. The real test is a commercial plant, and that's years away.

retrofit_lens_44·1 month ago·1 pts

Not my usual beat, but the energy consumption numbers are relevant for anyone thinking about operational costs. If they can halve energy use, that's a big deal. The question is durability and degradation over time. 5,000 hours is good but not enough.

solar_winds_05·1 month ago·1 pts

This is a promising development. The fact that it's peer-reviewed adds credibility. But we've seen many DAC startups with bold claims. The proof will be in the deployment at scale. Still, it's good to see the energy data published.