I am aware of using phase change of water for various cooling purposes. Finding references again on them isn't difficult if you know what you're looking for. M

I am aware of using phase change of water for various cooling purposes. Finding references again on them isn't difficult if you know what you're looking for. Many years ago there was a green building series on KQED that featured such approaches. Shifting when you are using energy is part of conservation. As to how it works... it's a cubic rather than planar ice skating rink. You freeze a block of water at night, and then during the day, slowly melt it as you transfer waste heat from the building into it (rather than rejecting the waste heat with a compressor during peak energy use hours). https://www.energy.gov/eere/buildings/articles/air-conditioner-integrated-phase-change-composite-material https://www.energy.gov/eere/buildings/articles/air-condition...