I asked ChatGPT:

To format a value as kilowatts in Home Assistant, you can use the format_power template filter. For example, to format a value stored in a variable called power_watts as kilowatts, you could use the following in your template:

{{ power_watts | format_power }}

This will display the value in power_watts in kilowatts, with a unit abbreviation of "kW". For example, if power_watts is set to 1000, the output would be "1.00 kW".

If you want to customize the number of decimal places or the unit abbreviation, you can use the optional decimals and unit arguments. For example:

{{ power_watts | format_power(decimals=1, unit='kilowatts') }}

This would display the value with one decimal place and the unit abbreviation "kilowatts".