As of 2015, Berko unit heaters use electricity and require between 2,000 and 32,000 watts of power. The Berko unit heater model HUH724ST, for example, is able to generate up to 26,000 BTUs of heat per hour. Berko recommends this model for garage and shop use.
A larger Berko unit heater, such as the HUHAA1024 model, requires a larger power input. This particular model requires between 7,500 to 10,000 watts of power and can produce up to 34,120 BTUs per hour. A larger cabinet unit heater model, such as the CU900, can use between 2,000 to 32,000 watts depending on the size of the unit that is installed.