Heat pump takes energy from two sources, power grid and outside environment: air, landmass or water (there are even air+land models etc). Their energy output is always less than sum of sources, so their efficency is never over 100%. But as the ambient land/air/water heat is generally ”free” then we seem to get 3-500% economy. I have never even seen the technical/physical efficiency numbers for heat pumps as consumers do not care about this.