In a recent report NABERS: Lessons from Twelve Years of Performance Based Ratings in Australia, Exergy Australia Pty Ltd managing director Paul Bannister talked about the lessons learned since the rating was introduced and described a number of challenges which lie ahead.
Bannister argues the success of NABERS is demonstrated by its widespread industry adoption. Starting with only a few ratings in 1999, the system grew to a market penetration of 66 per cent for energy by floor area and 41 per cent for water ratings by 2011.
Along the way, it has encouraged commercial property owners to aim higher. Major portfolio investors such as Investa, Colonial First State and General Property Trust boast portfolio rating improvements from 2.6, 2.6 and 2.7 stars in 2003, 2005 and 2006, respectively, to averages of 3.99, 4.1 and 4.6 stars in 2011. Over the six year period ending 2011, Investa delivered a 43 per cent improvement in portfolio emissions and water consumption intensity.
Bannister also talks about how NABERS has expanded in scope and now includes ratings for hotels and shopping centres as well as incorporating performance based tools for office indoor environment and waste.
He lists three important factors that contributed to the scheme’s success:
1) Base Building/Tenancy Split
Unlike some other schemes such as Energy Star, NABERS allowed for a separate rating of the base building in a manner which is independent of the tenants, meaning that a base building’s rating can be used as a generic measure of building efficiency irrespective of current tenant behaviour.
The ability to do this encouraged owners to upgrade building stock knowing that by doing so they would get the benefits of higher ratings no matter how their tenants responded.
2) Government Procurement
As tenants, public sector clients are large, long-term and low-risk, meaning an ability to attract them influences building valuation for the better.
Therefore, Bannister says, incorporation of the base building ratings into government procurement requirements played a significant role in turning the NABERS rating tool from an object of technical interest to one of commercial interest.
3) Corporate Sustainability
As the benefits of healthy and sustainable buildings become better known to corporate tenants, the ability of building owners to differentiate their buildings on environmental grounds through ratings systems such as NABERS and Green Star has become increasingly important.
Bannister says the NABERS story to date has delivered important lessons. Achievements of energy/water use reductions of 40 per cent or more are feasible using only conventional technology, while ratings of 5.5 are possible with modulations of standard technology. Ratings in sectors such as offices and retail are particularly effective in driving market transformation due to the demand of tenants and the general public for healthy and socially responsible office and retail space. This effect is less noticeable in hotels, where consumer drivers are not as strong.
There have, however, also been challenges. Regulation for mandatory buildings ratings through mechanisms such as the Building Energy Efficiency Disclosure Act, for example, have brought politics into the equation and made system change more difficult.
Overall, however, Bannister says, the story of NABERS in Australia to date has been one of enormous success.