HARNESSING
NATURE
Hydronic heating and cooling technologies use earth and air as energy sources, as these two Stiebel Eltron case studies demonstrate. AUTHOR: CLARISSA VAN EMMENES
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educing the energy demand of residential buildings has become a key focus area of the ongoing effort to shift towards a more energy-efficient future. Heat pump technology is evolving rapidly, causing builders to take notice as the technology improves and becomes more affordable—particularly when you consider that nearly 80% of the energy consumed in the home is used for heating and hot water. The following case studies look at two increasingly popular and efficient hydronic heating technologies used in New Zealand homes.
Geothermal heat pumps Geothermal heat pumps, also known as ground-source heat pumps, utilise energy harvested from the ground to provide hydronic heating, cooling and hot water efficiently. These heat pumps achieve a high coefficient of performance due to the stable temperature of the Earth’s surface. According to Marti Smith, director at Heated in Arrowtown, consumer awareness and uptake levels of geothermal heat pump technology varies. “While there’s quite good consumer awareness of the technology, there’s also a resistance to commit as most Kiwis are building for profit. However, most of my clients are building dream or retirement homes and are happy to spend to save.” Typically, the capital cost on geothermal heat pumps is higher, but so are the savings—and they’re instant. According to Heated client Jeff Desbecker, who installed geothermal heating in his approximately 450m2 new build in Lake Hayes, he was able to enjoy lower energy
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nzplumber
Three 80m deep boreholes were needed for this geothermal hydronic heat pump installation for underfloor and radiator heating.
