This is an excerpt from EERE Network News, a weekly electronic newsletter.
DOE Helps Develop an Energy-Efficient Water Heater
A new 50-gallon water heater with 90 percent thermal efficiency has been developed by A.O. Smith Water Products Company in a three-year collaboration with DOE and TIAX LLC, a leading engineering product development firm. To achieve the high efficiency with only a modest cost premium, the new water heater employs a glass-lined helical-coil heating element made from carbon steel, rather than stainless steel. The new "Vertex" water heater combines high energy input with efficient combustion to deliver performance similar to a 75-gallon tank. The high rate of energy production also allows the tank to maintain a temperature rise of 45 degrees Fahrenheit with a flow rate of three gallons per minute, which means that under most conditions, the water heater will endlessly provide hot water for a shower with a low-flow showerhead. See the A.O. Smith press releases on the collaboration (PDF 121 KB) and the Vertex water heater (PDF 109 KB). Download Adobe Reader.