Case studies

Soil moisture metering is a good investment for farmers who want to stop over-irrigating and cut their energy costs, according to Lincoln University Dairy Farm manager Peter Hancox.

Installing a soil moisture metering system helped him avoid unnecessarily irrigating an 80-hectare block on at least 32 days during the 2008/2009 growing season-and cut his power bill by more than $2000.

After installing a permanent magnetic stirrer in their gas-fired furnace, the aluminium extrusion and fabrication manufacturer, MCK Metals is saving 6.8 per cent in gas energy consumption.

The permanent magnetic stirrer not only reduces the melting time required, it also increases the amount of aluminium melted per hour.

In addition to the energy savings, the stirrer delivers other benefits: its maintenance free, easy to operate, and has a large circulation capacity. It also reduces wastage and improves product quality.

This farm installed a heat exchange system - it extracts the heat from the waste water and uses it to pre-warm the incoming water in the dairy shed. It reduces energy use as less energy is needed to heat each new batch of water to the 85 degrees celsius required for the next wash.

Monitoring has shown that the system is on target to achieve an annual energy saving of 30%. That equates to a cut in CO2 emissions of about one tonne a year.

Canterbury Laundry Service replaced two steam powered dryers with LPG direct fired dryers and cut its annual energy costs by $46,000.

The move also cut the company's CO2 emissions and boosted its operating capacity.