Building energy efficiency standards are regarded as an effective means of reducing or eliminating the greenhouse gas emissions of residential and commercial buildings.
National standards for building energy efficiency
The Australian Government has conducted studies into the greenhouse gas emissions of residential and commercial buildings. These studies show that the building industry must face the challenge of becoming more environmentally sensitive while remaining economically efficient.
In March 1999, following wide consultation, the Australian Government and the building industry reached a landmark agreement on a comprehensive strategy aimed at making Australian buildings more energy efficient.
The strategy encompasses:
- Australian Government and building industry support to encourage voluntary best practices in building design, construction and operation
- The elimination of worst energy performance practices by incorporating a single standard for minimum performance requirements into the Building Code of Australia
State standards for building energy efficiency
- The ACT House Energy Rating Scheme (ACTHERS), requires new or previously lived in residential homes to have an Energy Efficiency Rating (EER) Statement, prepared by an accredited ACTHERS assessor, if they are to be sold. As of the February 2006, the required software used in assessment is FirstRate, Version 3.1 or Version 4.
- In Victoria all new homes built since July 2004 have been required to achieve a 5 Star rating. This means it is compulsory for new houses to have:
- 5 Star energy rating for the building fabric, and
- A rainwater tank for toilet flushing or a solar hot water system, and
- Water efficient shower heads and tapware.
- All new homes and apartments in Victoria must comply with the 5 Star standard.
- The average energy efficiency rating of houses in Victoria was only 2.2 stars before the introduction of 5 star standard.
- From 1 May 2008, the 5 Star standard will be extended to cover alterations to homes and relocations of existing homes.
- In South Australia, all new homes (and alterations to existing homes) are required to achieve a 5 star rating. This requirement was introduced on May 1, 2006.
- In Western Australia in 2007 the State Government introduced further energy and water usage regulatory requirements. 5 Star Plus consists of two codes: the Energy Use in Houses Code, which requires a minimum standard of energy performance for a hot water system; and the Water Use in Houses Code, which includes provisions for alternative water supplies, efficient fixtures and fittings, and grey water diversion.
It is clear that the proliferation of different State-based standards in Australia is leading to some inconsistencies between states and duplication of effort. There is an opportunity to introduce national mandatory 6 star ratings for commercial and residential buildings as one of the means of reducing carbon emissions associated with buildings.
Germany has had stringent energy efficient standards for buildings for some time. More recently, they have introduced the requirement for buildings to generate 20 percent of their energy requirements, which both encourages greater energy efficiency and the installation of renewable energy sources such as solar power.
The Leadership in Energy and Environmental Design (LEED) Green Building Rating System encourages and accelerates global adoption of sustainable green building and development practices through the creation and implementation of universally understood and accepted tools and performance criteria. LEED was developed by the U.S. Green Building Council (USGBC), and provides a suite of standards for environmentally sustainable construction.
Opportunities for the future
In Australia, average energy-related emissions for new dwellings with five star energy rating has increased above those of existing dwellings, mainly due to people buying inefficient appliances and lighting and building larger homes.
Five star building standards need to be further improved to a 6 star level that includes full assessment of solar building design and the appliance energy efficiency standards.
We need to set a target of net-zero energy construction as the standard for all renovations and new buildings. This means that buildings could be energy neutral in the long term by a combination of passive solar design, solar panels and hot water systems and energy efficient appliances.