In January 2026, a small California company called Noon Energy ran a real-world demonstration that got attention in a space full of vaporware announcements: a single shipping-container-sized system that stored energy for over 100 hours. For context, grid-scale lithium-ion batteries typically run between two and ten hours before they run dry. The gap is one of the primary reasons renewable energy still depends on fossil-fuel backup: the sun goes down, the wind stops, and grid operators have no buffer deep enough to carry overnight or multi-day demand. Noon's founder and CEO, Chris Graves, is a former NASA engineer who helped develop a technology to split carbon dioxide on Mars into oxygen for rocket fuel. He realized the same electrochemical process could store energy on Earth.
The core technology, which Noon calls ultra long duration energy storage, works by capturing CO2 from the atmosphere and splitting it into carbon and oxygen. The solid carbon becomes the storage medium inside the battery; the oxygen is released. To discharge, oxygen is recombined with the carbon in a solid oxide fuel cell, releasing electrons as electricity. The carbon is released back to the atmosphere, resulting in no net CO2 change over a full charge-discharge cycle. Noon claims their levelized cost of storage at 100-hour scale comes in around 5 cents per kWh, compared to roughly $1.20 per kWh for lithium-ion at equivalent duration. The system also reportedly uses less than 1 percent of the critical minerals required by a comparable lithium battery, which is significant given ongoing supply chain concerns around lithium, cobalt, and manganese. Funding backers include NASA, the National Science Foundation, and the California Energy Commission.
The honest caveats are worth stating clearly. Round-trip efficiency sits somewhere between 60 and 80 percent, well below lithium-ion's 85 to 95 percent. Noon does not position this as a replacement for lithium-ion; the intended role is as a deep-buffer layer that feeds into shorter-duration lithium batteries for immediate use, in the same way pumped hydroelectric storage works today. Pumped hydro operates at roughly 70 to 80 percent efficiency and is widely considered economically viable despite that limitation, so efficiency alone is not disqualifying. What matters more is whether Noon can manufacture and deploy at scale without the cost rising to meet the competition. Graves told industry media in January 2026 that the technology has reached a readiness level high enough to begin production-line manufacturing, which puts this somewhere between a promising prototype and a commercially deployed product.
The broader industry context matters here. Long-duration energy storage has been a graveyard for well-funded ideas: flow batteries, compressed air, gravity storage, and thermal systems have all attracted serious capital and delivered modest real-world deployments. Noon's carbon-air chemistry is genuinely different from prior attempts, and the Mars connection to a proven NASA program is not just a story; the underlying electrochemistry has been validated outside a laboratory. But the distance from a shipping-container demo to grid-scale deployment has humbled larger companies than this one. Watch the quarterly production figures, not the press releases.
Bottom line: Noon Energy is solving the right problem with a credible approach and unusual backing. If their production-line claims hold and costs scale as projected, this is a legitimate candidate for the layer of storage the grid actually needs: not four hours, but four days. That said, the long-duration storage space has a long history of promising demos that never reached meaningful scale. This one is worth watching closely, not celebrating prematurely.