11 May 2006
HEEPs of Research on Energy Efficiency
The call by Wel Networks Chief Executive Mike Underhill for greater insulation in New Zealand building construction, is
supported by numerous research projects undertaken by BRANZ Ltd.
"BRANZ research over the past decade has investigated the use of energy in New Zealand homes, and has lead to an
improved understanding of the opportunities for energy efficiency," according to BRANZ Science Communications Manager,
Chris Kane.
“There is no question that better insulated buildings will reduce energy waste when it comes to heating and cooling.
However, before getting into a discussion about how this information might influence future options of energy generation
and supply, other, more significant factors also need to be understood,” he said.
The internationally leading Household Energy End-use Project (HEEP) and Zero and Low Energy House (ZALEH) research
projects have improved our knowledge of how New Zealanders use energy – some in strange ways: for example people in
Hamilton go to bed earlier than most other parts of the country.
The average New Zealand home uses about one third of its energy for space heating, one third for water heating and one
third for everything else.
"We are looking for opportunities to improve each of these uses of energy," said Mr Kane.
Insulation of the roof, wall, floor and windows will help reduce the need for space heating, and improved insulation of
the hot water cylinder and piping will impact on wasted energy there.
The other one third goes into a wide range of uses, including the refrigerator, lighting, entertainment (TV, DVD
players, Computers and games) as well as kitchen and laundry appliances.
"There is also the opportunity to look at fuel switching - it may be more efficient to produce hot water by heat pumps,
solar water heating or natural gas, than using a simple resistance element hot water system" he said.
Kane is emphatic that holistic consideration of the issues above will result in much greater energy savings, and
associated non-energy benefits, than consideration of one aspect alone, such as insulation levels. “Understanding to
what end use energy is put – and why - is the most useful tool in planning future energy needs. For example, HEEP has
identified that houses which are heated electrically tend to have the lowest indoor temperatures – this is a very
important factor to be considered in planning for energy use in the future. It’s also important to note that energy use
does not just mean electricity use – as mentioned, there are alternatives to electricity”
For over a decade, BRANZ has been researching actual energy use, and annually publishes the Household Energy End-use
Project (HEEP) report. For further information about HEEP please download a free copy of the Year 9 Report
www.branz.co.nz.
ENDS