Storing solar electricity as hot water: The Sunamp Heat Battery
As solar power and other intermittent renewable technologies become more commonplace, energy storage is going to become an ever bigger priority. While many companies are exploring lithium ion and other conventional battery technologies for homes and businesses, others—like UK-based Sunamp—have a slightly different approach:
Why not use excess solar electricity to meet a home's hot water and even space heating needs?
We have seen similar ideas before. Back in 2012 I reported on another UK company that was helping to divert solar electric power to people's water heaters, rather than selling it back to the grid. Sunamp appears to take this a step further, storing the excess energy in the same kind of phase change material used in those hand warmers you can buy from camping stores.
When hot water is needed, it's then passed through the Sunamp heat battery—bringing it up to temperature using the energy that would have otherwise gone to waste or been sold off to the grid. Alongside the potential efficiency gains, the Sunamp folks tout another impressive advantage: they've been testing a Sunamp unit for 20,000 cycles on cycle testing rig and it's still at 100% of capacity. That's the equivalent of 55 years of service with no loss of capacity.
Sunamp are also working on another interesting concept. In the video below (from the fabulous Fully Charged), they describe a proposed scheme to move waste heat from Avonmouth—a port and industrial area just outside Bristol, England—to Bristol city center by barge along the river Avon. They plan to do this using shipping container-sized heat batteries, which they could then discharge into a district heating system that's currently in the works there. This won't just save energy, it will also reduce fuel combustion in the city center, improving air quality and health in a major urban area.
As always, if you dig this video from Fully Charged, please consider contributing to Robert Llewellyn's Patreon page.