It's far less useful than a battery, though, because heat is only good for heating things, which means you also need to provide fuel to convert it into electrical or motive applications. like computers and cars.
It’s far less useful in the general case, but substantially cheaper and more efficient in a special case that consumes a substantial chunk of the primary energy used. It’s not as if battery storage is lossless. Currently, heat generation is often done using primary energy, but that too, needs to be reduced if we want to tackle CO2 production levels.
You can also use the same principle to store cold in summer: Cool down a vat of coolant (though water likely won’t do) at times when you have electricity surplus and use it later.
Certainly, that not solving all problems, but it can kill battery usage for some cases.
It may be more efficient to time shift heating loads than to time shift electrical availability with batteries.
If heating loads are a significant amount of the total load, then this would help reduce the need for peaker plants or battery energy storage. And, if done properly, it provides a cost savings to the utility user too.
You can also use the same principle to store cold in summer: Cool down a vat of coolant (though water likely won’t do) at times when you have electricity surplus and use it later.
Certainly, that not solving all problems, but it can kill battery usage for some cases.