A Florida jail has improved its energy efficiency credentials by installing tankless water heaters.

Indian River County Jail in Vero Beach replaced its malfunctioning boiler and 300-gallon storage tank with eight of the devices, which use a powerful burner to quickly heat incoming water to the set temperature.

They activate only when a fixture is turned on and cease heating once it is off, allowing improved energy efficiency and lower fuel costs because the heater is not constantly firing on and off to heat stored water.

The jail needed to ensure the equipment it bought was not only energy-efficient but also long-lasting and reliable to avoid denying 156 inmates access to hot water and potentially triggering riots.

Administrative Lieutenant Adam Bailey said: “Having spent $64,000 (£47,700) on the eight tankless water heaters, we saved around $14,000 (£10,440) over [traditional] tank water heaters.”