Maintain your water heating systems – inspect them regularly, repair leaks and fix dripping taps.
Set thermostats to the right temperature – overheating water is costly.
Insulate hot water pipes. If your hot water cylinder is warm to touch, install insulation wrap.
Install timers to heat water only when required or, if your plan allows, to take advantage of off-peak pricing.
Choose the right sized hot water cylinder for the job. Place hot water cylinders in a sheltered place on the sunny side of the shed.
Install a heat exchange system which chills milk while generating hot water.