I compared it to my 150 watt hydro farm, even changed the bulbs. The sun 150w PS pulls noticeably! The amperage is less than that of a hydroelectric power station. Solar system = 1.5A or less after 60 minutes of operation Hydrofarm = 3.8A or MORE after 60 minutes of operation So the solar system takes less to get 150W of light, much less! A hydroelectric power station requires about 300-400 watts to produce 150 watts of light. The ballast consumes the most energy.