Which is more economical, air-energy heat pump hot water or solar hot water?

This problem can be divided into several situations.

Air energy heat pump saves the most hot water.

If it is a unit that consumes a lot of water, such as hotels, hotels and factories, it can be said that air energy heat pump hot water is the most economical.

Solar hot water is relatively cheaper.

If it is domestic water, that is to say, the water consumption is about 500L, and the solar energy is relatively less, but it needs electric auxiliary heating in rainy days, and it will cost more electricity in rainy days.