Available Modules

Energy-Efficiency Enhancing Technologies: Plastic Tanks

Conventional water heater tanks consist of a metal outer jacket lined with either glass or cement. Due to its lower heat conductivity characteristics, plastic water heater tanks offer an opportunity for reduced standby losses and energy savings. Plastic tanks cannot be used with standard center-flue gas fired storage water heaters because the plastic cannot withstand the high temperatures produced by the flames. Plastic tanks are an option for gas-fired indirect water heaters.

Two options exist for the construction of plastic water heater tanks. One method uses a seamless, blow-molded polybutylene inner tank with a filament-wound outer tank. The second option is a steel tank with an internal plastic tank. This type consists of a thin steel shell with its interior coated in plastic.

An advantage for plastic tanks in electric water heater models is an improved process for insulating the tank bottom.