Hot Water Energy

Energy for the production of hot water is a relatively low-energy use in most plastics processing sites. Hot water is primarily used for hygiene and personal washing; however, it is used at every site, and energy savings are easily possible.

Action:

Fit time controllers to all hot water boilers.
Condensing boilers are the best option for new or replacement small hot water systems.
Check the water storage temperature if the storage is some distance from the point of use. The storage temperature should be 60-65°C but no higher, otherwise heat losses will be higher.
Check that all hot-water storage tanks and pipe work are adequately and fully insulated. Fit lagging (insulation jackets) to all local hot-water storage tanks if insulation is not present.
Ensure that no hot water taps are leaking, and preferably fit automatic sensor-controlled taps.
Check tap water temperature regularly. It should be 55-60°C but no higher, otherwise heat losses will be higher.>
Consider fitting local “on-demand” hot water heaters to avoid long pipe runs. These can reduce energy use considerably, especially in summer when other demands on a centralized system are low.

Note: Dr. Robin Kent is the author of Energy Management in Plastics Processing, published by Plastics Information Direct, and managing director of Tangram Technology Ltd., consulting engineers specializing in energy management in plastics processing. rkent@tangram.co.uk.