Energy efficiency upgrade potential of existing Victorian houses

Energy efficiency upgrade potential of existing Victorian houses


Ian McNicol

Organisation of Presenter:

Sustainability Victoria, Australia


The paper provides an overview of a number of projects undertaken to understand the energy efficiency upgrade potential of existing (pre-2005)houses in Victoria, Australia. The On-Ground Assessment study used field surveys to obtain data from a reasonably representative sample of 60 houses, identify their efficiency status, assess their practical upgrade potential, and model the costs and savings of the upgrades. It found an average House Energy Rating (HER) of only 1.81 stars. The analysis identified the applicability of the different upgrade measures and their relative cost-effectiveness, as well as the greenhouse gas savings. In addition to the average impact across the 60 houses, and for those houses in which different upgrades were modelled, the study identified the diversity of outcomes achieved, and explored the underlying reasons for this.
A series of separate energy efficiency retrofit trials were also undertaken to assess the actual costs and qualitative and quantitative impacts of 9 key efficiency upgrades. The impact of the upgrades was determined from a ‘differential analysis’ that compared the pre- and post-retrofit monitoring periods. The studies also explored the extent to which the rebound effect reduced the level of savings achieved by the energy efficiency upgrades.