You are viewing an archived copy of this website captured Mon Dec 23 19:52:36 AEDT 2013


Energy Efficiency

What is energy efficiency?

Energy efficiency basically means using less energy to achieve the same level of outcomes or performance, or improving the level of outcomes or performance from the same amount of energy.  For example, replacing a 100 W incandescent light bulb with a 10 W LED light bulb will provide the same level of light output using 90 per cent less energy.

Energy conservation is slightly different.  It basically means reducing actual energy use, for example through reducing the need for requiring energy in the first place. Switching off lights in unoccupied rooms, heating occupied zones rather than a whole house, and lowering the heater thermostat, are all examples of energy conservation.

Historically there has been little focus on energy efficiency, mainly because of low energy costs. However, with rising costs and growing concerns relating to the impacts of energy related greenhouse gas emissions, there has been an increasing focus on improving energy efficiency and conservation.

The potential benefits of improved energy efficiency are substantial in terms of reducing energy consumption and associated energy costs and greenhouse gas emissions. In addition, implementation of energy efficiency measures can be very cost effective, with the value of savings over time typically outweighing upfront costs, delivering net financial benefits to the consumer within a short period of time.

Equipment energy efficiency

Mandatory Minimum Energy Performance Standards (MEPS) and Energy Rating Labels (ERLs) apply in Australia to a broad range of common electrical appliances used in the residential, commercial and industrial sectors.

MEPS ensure that equipment below a certain standard is not available for sale, and ERLs allow consumers to make an informed choice when purchasing new appliances. Together they have been very successful in improving equipment energy efficiency. For example, a report assessing the Australian Government's Equipment Energy Efficiency program estimated net economic benefits of more than $22 billion by 2024 with reductions in household electricity consumption by 2020 approaching 30 per cent compared to business as usual (Wilkenfeld & Associates 2009).

More information on equipment energy efficiency, including product comparisons, can be found at the energy rating website.

Residential building energy efficiency

The energy efficiency of buildings is essentially an indicator of the amount of heating and cooling required to maintain thermal comfort. This is impacted by many factors including levels of insulation, location of windows, building materials, shape, size and orientation and suitability for the local climate. Household energy efficiency requirements were first introduced into the Building Code of Australia in 2003.  Many houses built before this date have low levels of energy efficiency and require high levels of energy to heat and cool.

Houses are rated on a scale of 1 to 10 stars using the Nationwide House Energy Rating Scheme (NatHERS) which assesses the potential thermal comfort of homes.  1 star means the house provides only minimal moderation of hot and cold weather, and high levels of heating and cooling will be required to maintain thermal comfort. 5 stars indicate good thermal performance, however some heating and cooling will usually be required to maintain comfort. 10 stars indicate outstanding thermal performance, with the need for heating and cooling unlikely.  Many houses built before 2003 would only rate 1 or 2 stars.

Building energy efficiency is of particular relevance in Tasmania because of the colder climate and the high level of space heating requirements. Tasmania adopted a minimum 4 star requirement for new houses in 2003, which was increased to a minimum 5 star requirement in 2010. A minimum 6 star requirement is to be adopted from July 2013. Other Australian states and territories (other than the Northern Territory) adopted a minimum 6 star requirement in 2011.

Houses with poor star ratings and inefficient appliances are typically required to consume large amounts of energy to run the household at a satisfactory level of comfort and service. This is particularly the case if operating inefficient forms of heating such as bar radiators. This can place low income households under financial pressure.

Having an energy audit or assessment carried out by a qualified assessor can be a very effective way of identifying the most cost effective energy efficiency improvements in a household. This also provides an opportunity for home owners to increase their understanding of how energy is used in the home and the advantages of energy efficiency improvements.

The Hobart City Council offers an insulation rebate scheme for landlords on the costs of insulating their rental properties.Click here for further details.

Commercial building energy efficiency

Energy efficiency standards for new commercial buildings are incorporated into the Building Code of Australia (BCA). In addition, large commercial buildings are required to obtain and disclose a building energy certificate when leasing or selling, which includes a National Australian Built Environment Rating Scheme (NABERS) energy star rating for the building.  Other commercial and community buildings can voluntarily obtain star ratings from NABERS or other rating schemes such as Green Star. Tenants and landlords can also voluntarily negotiate green leases.

Where can I find further information?

Further information on energy efficiency, including available assistance from the Tasmanian Government, can be found at the Earn Your Stars website.

To guide you through the benefits of an energy efficient home, the Tasmanian Government has produced four SAVEenergy SAVEmoney guides.

The Sustainable Living Tasmania website also offers a lot of useful advice on how to improve the energy efficiency of your household and reduce costs.

The Australian Governments Your Home website is also a very useful resource.