Skip to content
Thermal energy storage is pretty great, as phase-change energy storage is very consistent with its energy output over time, unlike chemical batteries. You also get your pick from a wide range of materials that you can either heat up or cool down to store energy. Here, the selection is mostly dependent on how you wish to use that energy at a later date. [Hyperspace Pirate] is mostly interested in cooling down a house, on account of living in Florida.
As can be seen in the top image, the basic setup is pretty straightforward. PV solar power charges a battery until it’s fully charged. Then an MCU triggers a relay on the AC inverter, which then starts the cooling compressor on the water reservoir. This proceeds to phase change the water from a liquid into ice. The process can later be reversed, which will draw thermal energy out of the surrounding air and thus provide cooling.
Although water is not the most interesting substance to pick for the
The cool side of the thermal storage system, chilling a car. (Credit: Hyperspace Pirate, YouTube)
thermal energy storage, it can provide 1 kWh of cooling power in 10.8 kg, or 92.8 kWh in a mere m3. This makes it much more compact as well as cheaper than chemical storage using batteries.
After charging the main compressor loop with R600 (N-butane), the system is trialed with a small PV solar array that manages to freeze the entire bucket of water. Courtesy of insulation, it’s kept that way for a few days, giving plenty of time for the separate glycol-filled loop to dump thermal energy into it and push cold air into the surrounding environment. This prototype managed to cool down [Hyperspace Pirate]’s car in just two hours, which is good enough for a proof-of-concept.
Instagram Engineering
Shopify Engineering
