Home Energy Efficiency ……. cost & comfort benefits
An energy-efficient home can be defined as one which requires the least amount of energy to provide a comfortable living environment. Many Tasmanian homes are poorly insulated but quite simple, low cost improvements can pay for themselves in lower energy bills.
This section considers only the fabric of the building, specifically insulation and draft-proofing. Heating, cooling and lighting technologies will be covered elsewhere.
Where to begin?
In many cases, the first step in home energy efficiency is to minimise the amount of heat that’s either leaking out of or, on hot days, into the home. This may seem obvious but it is often neglected, addressed instead with more costly remedies such as boosting either the heating or air-conditioner settings.
Cost of drafts & poor insulation
Poorly insulated, drafty homes are not only uncomfortable to live in, they are costly to run. Why?
Poor draft-proofing allows the outside air to flow through the home, drawn in by the suction created as wind outside flows over and around the house. The internal air is effectively ‘sucked’ out of the house and replaced by outside air which has to be either heated or cooled, resulting in unnecessarily high energy bills.
Poor insulation can cost an additional $4000 a year, compared to a well-insulated home as explained in this article from The Guardian:
Is my house poorly insulated?
Many Australian homes, particularly older ones, will benefit from improved draft-proofing and/or insulation. This is simply because most homes were built prior to the introduction of energy efficiency standards in 2003. Presently, new Tasmanian homes must achieve a minimum ‘6 star’ energy efficiency rating. Other States require a minimum 7 stars.
The average Australian home is estimated to be just 1.8 stars
Of course, an ‘average’ value is of little practical value but, although all new homes constructed since 2013 had to achieve a 6-star rating, most older houses fall between 0 and 3 stars and are much more costly to heat or cool. The chart shows how the energy required falls as the star rating increases—e.g., changing from 0 to 1 star reduces from almost 180 to under 120, reducing the energy needed by one third.
The table below, extracted from the NatHERS website shows the benefit of improving a Hobart home 0.5 to 3.5 stars reduces the energy requirement by almost two-thirds.
The chart shows how the annual home energy requirement reduces with a higher star-rating, showing from 1 (dark blue) to 6 (black) stars.
What to do next?
There are many sources of helpful information such as those shown below. For practical advice, and some idea of the costs involved, consider having a survey by an energy consultant. Some are shown on Sustainable Living Tasmania’s website (see: Our Staff | Sustainable Living Tasmania) (slt.org.au)
Useful Links
Tasmanian State Govt:
Climate Change: What you can do
Sustainable Living Tasmania: Take Action
RENEW.org The Key to Thermal Performance
