The weight and size of the batteries described pretty much means that only one, maybe two, batteries could be transported on a truck from the factory where the

The weight and size of the batteries described pretty much means that only one, maybe two, batteries could be transported on a truck from the factory where the excess heat is being produced to the house where the battery will be used temporarily. That battery then needs to be collected and transported all the way back to the factory for 'reheating'. That's not a cheap process. One battery: four factory-house trips involved. ( = 2 return trips from the factory to a house for a largish haulage truck) That's why I said that it probably would not be cost-effective for use in a domestic situation. On the other hand, the industrial use of these batteries would be efficient and cheap. The only transport required would be short-distance, in-house, and could be further cheapened by the use of rails and being pulled by electric haulers round and round the factory.