Heating and/or cooling can be shifted by hours, depending on the thermal time constant of the building. The better the insulation, the longer it can be shifted

Heating and/or cooling can be shifted by hours, depending on the thermal time constant of the building. The better the insulation, the longer it can be shifted. Texas had a problem because so many older buildings there are very poorly insulated. Thermal energy in general is very cheap to store. This is also true industrially, where thermal storage has long been used for regenerative recovery of waste heat, for example in various places in steelmaking. Thermal storage of heat derived from electrical power is now being proposed as a way to soak up zero or negative price electricity. There's a company based on work at MIT that's doing this, using moderately electrically conductive refractory ceramic bricks as combined storage and heating elements.