Simple fix cuts hot water cost

By Country News

This is the first article in a series on energy efficiency presented by GV Community Energy. 

Hot water is essential and costly for the operation of every milking shed and for less than $100 most systems could reduce the heating bill by about 20 per cent.

Poorly insulated pipes connected to within 2m of the hot water storage tank (and any fittings on the water tank that are warm to touch) can be a major contributor to cooling the water in the storage tank.

As water cools in these pipes and fittings, heat from the tank passes to them in a process that constantly ‘siphons’ heat from the tank.

Over the course of a 24-hour cycle this results in significant cooling of the stored hot water.

Significant energy savings can be made by simply insulating all pipes and fittings that are warm to touch within 2m of the tank.

Best practice insulation includes using a foam material coated with a reflective foil.

Lagging that doesn’t have this foil coat can be covered by a foil tape secured and sealed over.

Aluminium foil can be used as a cheap alternative (shiny side out) although it may be prone to rodent or bird damage.

Foil is very effective in reducing heat loss from the surface of insulation due to the shiny surface having a very low emissivity level and little heat will pass from its surface.

In contrast, a black surface such as black foam lagging, although a good insulator, is compromised by having a very high emissivity level and heat will continually leak/emit from its surface.

The most common installation faults are using lagging that is not UV stable (if exposed to sunlight), cut too short and exposing sections of pipe or fittings and not insulating the pressure release valve.

Not completely sealing the lagging when it is split for easy install over pipes at joints is another common fault.

All these shortfalls can be fixed easily with material costing less than $100 by most property owners — a job easily done between milkings.

—Geoff Lodge

chief executive officer

GV Community Energy