Evaporation occurs naturally through the venting system, but is expediated by the Envirolet™ features.
Non-Electric models use a 4" Wind Turbine, 12VDC Battery models use a 4" Wind Turbine and dual 0.26AMP Fans and 120VAC Electric models use a 500W Heater and dual 20W Fans.
120VAC Electric Waterless and Low Water Remote Systems use a 500W Heater, dual 20W Fans and a 4" Wind Turbine.