Standard Water Heaters
Most propane tankless water heaters are Energy Star-qualified electric standard water heaters are not.
There isn't a single electric standard water heater that qualifies for the federal Energy Star program, while most tankless propane units do. Why?
Because propane water heaters are significantly more energy efficient. This efficiency translates into real savings for homeowners. A propane water heater can cost less than half what it costs to operate an electric water heater and reduces greenhouse gas emissions by 60 percent. Electric water heaters simply can't compete with propane.
A standard propane water heater works in the same way that a natural gas water heater does. They also install just as easily and are widely available through many propane retailers and plumbing professionals.