You can calculate kilowatt from kilowatt-hour and hours, but you can't convert kilowatt-hour to kilowatt, since kilowatt-hour and kilowatt units represent different quantities.
The power P in kilowatts (kW) is equal to the energy E in kilowatt-hour (kWh), divided by the time period t in hours (hr):
P(kW) = E(kWh) / t(hr)
kilowatt = kilowatt-hour / hour
kW = kWh / h
What is the power consumption in kilowatts when the energy consumption is 15 kilowatt-hour for time duration of 3 hours?
P = 15 kWh / 3 h = 5 kW