Inefficient resistance heaters are found on all emergency diesel generators and these heaters operate most of the time. However, resistance heaters are very wasteful when compared to heat pumps. What is the best way to reduce waste (and back-up your heater)? Upgrade to a heat pump using GEO-THERMAL SYSTEMS, INC.® (GTS) patented technology. This is the most efficient way to heat emergency generators and—with thousands of installations over the past ten years—GTS has found that their customers usually save between 75% and 85% on electricity charges. Your emergency power system is wasting money/electricity every day unless you have upgraded to a GTS heat pump system.