Using a Heat Pump for costs on electric depends on the provider. A Heat Pump is not going to magically make your costs for use of electric or gas automatically go down. A heat Pump costs the same to use, as using a AC & Furnace. If you believe the hype that a heat pump is more efficient, than a high efficient 91% or better furnace & 16 SEER or greater A/C, it is false info.
I have heat pumps in dual fuel applications where the gas furnace is a 95% efficient furnace, and the heat pump heats the house for less money then the gas furnace can at any temp above 20°F. And on some of them, as low as 15°.
I have some dual fuel set ups that the gas heat is a boiler. And the heat pump runs even when its 0°F outside, and they save on their heating bill with both the heat pump running and the gas boiler. They use very little gas for heating, the heat pump does the majority of the heating, and their monthly electric bill and gas bill combined is less then what their monthly gas bill use to be when the gas boiler did all the heating.