By Leon Wurfel – Founder, Bueno Analytics
I like to joke that I only ever had one job before starting Bueno. This is true if you exclude working cafes, bars, delivering flyers, but my real professional history prior to starting Bueno was in energy efficiency consulting.
I was lucky to start working for a company called Exergy Australia (which out of you nerds gets the thermodynamics joke?) who’s founder Paul Bannister was the technical author of Australia’s Building Performance Standard NABERS (National Australian Built Environmental rating system). At the time Exergy was considered to be the leading authority on NABERS in Australia and they went on to be the technical authors of the NABERS Energy and Water schemes for Offices, Hotels, Shopping Centres and Data centres.
One year into my career there I was given a client to work with who were a company called “Colonial First State”. They were a REIT owned by the Commonwealth Bank in Australia. I went on a 5 year journey working with that client on their NABERS journey where they had set a goal of achieving a 4.5 star NABERS Energy target which they wanted to hit for the rating year 2012. We successfully hit that target and as part of that journey I got a lot of first hand experience as to what works, what doesn’t work and am writing this article to share some tips that I think will be helpful to anyone who is looking at NABERS across their assets.
Tip #1: Rate early
NABERS can be tough if you don’t have the right documentation in place. Without documentation or data the rating rules tend to force you to take a position that at least errs on the side of being punitive meaning that your building gets a rating that is worse than its actual performance.
Examples of these kinds of issues from my experience with the Australian scheme were:
- Getting to the end of the rating period and realising that you have a year’s worth of estimated gas bills
- Poor record keeping around after hours air conditioning calls or exclusion sub-metering
- Unclear lease clauses e.g. around service hours
- Exclusion sub-meters without verification certificates.
- Meter data gaps. NABERS now requires hourly trends for thermal exclusions. Sites with metering system issues have not been able to exclude the whole amount so its imperative to catch these early.
- Tenant early access documentation: Some landlords give tenants 3-6 months of early access, but if they don’t have the right documentation the assessors haven’t been able to include those periods in the NLA.
So one improvement that we made early on in the NABERS program was to start the rating process early and do the site visit 6 months into the rating period. This allowed us to get ahead of any documentation concerns as well as do a spot check on the rating performance of the buildings. This was a little bit of extra cost but was considered to be well worth it given that we had performance milestones to hit.
Tip #2: Get smart with your documentation
If you start rating your buildings and build NABERS into your sustainability program then you are usually making a commitment to follow up and re-rate the buildings on an ongoing annual basis. Probably about 80% of the work/cost involved with these ratings is in collating and reviewing the rating documentation to verify the site’s rating. This is a non-trivial amount of work for the NABERS Assessor as well as for the property management staff to respond to the documentation requests.
So my best advice is to build a register of NABERS relevant documentation. This will be a little bit of extra work in the first year but will make your assessor’s and your own staff’s lives so much easier in the long run. Build it into your NABERS ratings scopes for your assessors to update the register each year as they do their ratings. The benefits extend beyond efficiency but also give you a lot more procurement flexibility if you decide to change assessors at some point in the future.
NABERS celebrated 25 years of driving building optimisation in 2024.
Tip #3: Make the most of what you’ve got
We took the Colonial First State CPA portfolio from 2.6 stars to 4.5 stars over 5 years. The performance improvement broke down to:
- ~45% from capital works or churn of newer buildings into (and older buildings out of) the portfolio
- ~45% from operational improvements such as optimising BMS controls strategies and fixing maintenance items that were causing energy waste
- ~10% from addressing NABERS rating compliance issues.
The key takeaway is that more than half of the improvement came from high impact, low cost improvements to just getting the most out of what was already there. These were all items with <2 year paybacks that are no-brainers to do. If you don’t have an immediate performance target you can still get those capital works benefits but patiently through your regular capital lifecycle improvements over time.
This is of course the part of the article that is a shameless plug for Bueno. The whole reason that I started Bueno was because I saw the value of this stream of work first hand. Bueno’s software is effectively an automated team of Leon’s looking at your BMS data 24/7 catching things that are broken and looking for things to improve.
How did it end?
The portfolio achieved its 4.5 star NABERS energy rating 3 months ahead of schedule. This was a satisfying outcome that created real business value:
- $12M in energy savings
- $500k in water savings
- Most importantly it protected the marketability of the assets to tenants who at the time were starting to demand a 4 or 4.5 star energy rating as their minimum requirement for occupying new leases.
Any questions, feel free to message me on linkedIn or use our contact form:
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