Exemplary Energy’s work on Precipitation Disaggregation, converting daily data as was recorded by the Bureau of Meteorology (BoM) in the 1990s and much of the 2000s, has been reported on in Exemplary Advances during its development over several years. It was presented in extended abstract format at the Asia Pacific Solar Research Conference (APSRC) in December 2024. Our full paper on that ground-breaking work has now been published in the learned journal Stochastic Environmental Research & Risk Assessment.

Our team has successfully developed an innovative machine learning approach that generates high-resolution precipitation data (mostly rainfall) critical for modern building performance and hygrothermal simulations such as in WUFI. Our work introduces a long short-term memory (LSTM) neural network that can disaggregate daily precipitation readings into half-hourly intervals—a significant advancement over existing machine learning models limited to hourly resolution. 

The table below summarizes model performance across the five climate zones, showing Root Mean Square Error (RMSE), wet half-hour detection, and skill score accuracy on test data set. 

Location	NCC Climate Zone	RMSE (mm)	Wet Half-Hour Detection (%)	Skill score (Half-Hourly)
Cairns	Zone 1	0.6899	65.88	0.68
Brisbane	Zone 2	0.5670	60.68	0.65
Sydney	Zone 3	0.5136	70.85	0.73
Melbourne	Zone 6	0.2345	55.86	0.62
Canberra	Zone 7	0.2857	68.14	0.70

Note:

• RMSE measures average prediction error (lower is better). 
• Wet Half-Hour detection shows the percentage of rainy half-hours correctly identified in the exact half-hour, reflecting timing accuracy. 
• Skill score evaluates how well the model captures the frequency and distribution of precipitation events (higher is better, 1.0 is perfect). 

In comparison to the previous model (Ferrari et al. (2022)), the RMSE improved by over 30% for Canberra (0.4513 vs 0.65 mm). 

In the Australian context, the extreme weather conditions like draughts and heavy rains make precise data essential. By incorporating meteorological variables and a specialised normalisation layer, our model maintains statistical consistency while preserving daily precipitation totals. 

This breakthrough enables more precise modeling for building designs and water management systems, especially valuable in regions like late 20^th century Australia where historical sub-hourly precipitation data is limited.

You can read the full paper here: https://doi.org/10.1007/s00477-025-02996-0

Weather and climate files incorporating precipitation data in ACDB and EPW formats are available through our sales portal at no extra charge.

We will keep readers informed as to what, if anything, DCCEEW is doing in response to our generous offer to save the Department both money and time and their response to our formal submission just lodged with their Procurement division. Meanwhile, for the full story to date, read here; and readers can access a free sample file for themselves here.

On Tuesday 13 May, the ‘caretaker’ arrangements for the election formally ended with the swearing in of the new ministry (see below).  Exemplary Energy will now pursue this matter on several fronts in a continuing effort to eliminate this waste of public funds and bring appropriate competitive procedures to this routine but exacting task.

18 August 2025

On 18 August, in response to a query from the Hon. Josh Wilson MP, Assistant Minister for Climate Change and Energy, DCCEEW has responded with the straight bureaucratic dead bat of advising me of the formal complaints channels of the Department of Finance Procurement Coordinator and the Commonwealth Ombudsman.  We will, of course, use those channels if DCCEEW’s stance remains so self-absolving; but we remain hopeful that an enquiry from the Shadow Minister might elicit more integritous administration in a shorter time frame.
Accordingly, we have now notified Shadow Minister for Energy and Emissions Reduction, the Hon. Dan Tehan MP, of this gross waste and failure of internal process.

13 May 2025

We wrote again to the Deputy Secretary Procurement on 16 May setting out the deep flaws in the formal reply but have still received no response in the subsequent months. Accordingly, we have raised the wasteful and delaying decisions made by the NatHERS team with Assistant Minister for Climate Change and Energy, Josh Wilson, and to Minister Chris Bowen as a courtesy. As well as placing DCCEEW’s apparent mal-administration on the public record with several journalists with known interests in the field, we have advised Senator Barbara Pocock (Greens, SA) who regularly holds departmental secretaries to account for waste under their control.  We have also advised Senator David Pocock (Independent, ACT, no relation) because of its negative parochial impact.

If the DCCEEW silence continues, we will also notify Shadow Minister for Energy and Emissions Reduction, Dan Tehan, early next week.

8 April 2025

Exemplary Energy lodged a formal complaint with the DCCEEW Deputy Secretary responsible for procurement setting out how its NatHERS team has apparently disregarded the public interest by adopting an invalid rationale and procedure:

Limited Tender Condition: 10.3.e. Additional deliveries by original supplier intended as replacement parts, extensions, or continuation for existing goods or services for compatibility.

Our submission challenged that claim on two grounds:

1. NIWA (see under 23 March) does not qualify as the “original supplier” as required by the condition, but rather is merely the “immediate past supplier”.  The original development of these files was conducted by CSIRO and the Bureau of Meteorology in the 1980s and there have been many updates since then.
2. The cited condition pertaining to “replacement parts, extensions, or continuation for existing goods or services for compatibility” is inapplicable in this case.  The file format in question has remained a published standard since its original development, requiring no special compatibility considerations.

We then pointed out our long-standing unconditional offer and the negative outcomes that naturally flowed from its apparent dismissal:

We had already completed the required work as of September last year and offered to supply the data to DCCEEW at no cost.  We also made that unconditional offer public (citing the second article in ‘Exemplary Advances’ of September 2025) and promoted the purchase of these climate files through our sales portal for $100 + GST per location.  Clearly this makes it possible for anyone to fulfil this subsequent contract of concern for under $7,000.  Had your department taken up our offer of the free files, it would have:

• Saved considerable public expenditure; and
• Promptly replaced the outdated NatHERS climate files, which have been propagating misleading design guidance throughout the housing industry based on decade-old data (notably excluding Australia’s warmest decade on record).

Our submission closed with our recommendation and request that the contract be cancelled to avoid any further waste of public resources and confirmed to DCCEEW that:

Our unconditional offer to provide these files at no charge remains valid.

We will advise readers of the progress or the outcome of this submission in future editions of  ‘Exemplary Advances’.

23 March 2025

We received a reply to our email of 4 March the key part of which comprised this advice:

“In accordance with the Commonwealth Procurement Rules, the department conducted a limited tender process for the purposes of updating the Representative Meteorological Year (RMY) climate files up to the end of 2023. The outcome for the climate file procurement has been published on Austender: https://www.tenders.gov.au/Cn/Show/d3a0e47f-c5c0-40cd-98db-7a18fcaae703.”

This led us to Contract Notice View – ‘CN4126887‘ which revealed that the ‘Limited Tender’ had been let to the New Zealand company National Institute of Water & Atmospheric Research Ltd (NIWA) for AUD $116,375.00 with the purported rationale being given as Limited Tender Condition: 10.3.e (see above under 8 April 2025).

4 March 2025

As the most senior officer included in this email thread, I presume that you take responsibility for Leonie’s silence for over three months now.  I can understand that DCCEEW may not want to be candid with us; but we believe that blunt silence is counter-productive to progress with the reforming of the NatHERS climate files.  We believe that reform is urgent for NatHERS processes and protocols to contain the damage that it is doing to the energy and comfort improvements in the residential sector; and to the good work that your division is generally undertaking.

We will, of course, include this advice (or DCCEEW’s ongoing silence) in the next edition of ‘Exemplary Advances’ planned for dissemination early next week.”

3 February 2025

We have not been graced with a reply in over two months now. Please advise us now what DCCEEW has done, or intends to do, to solve the problem of old NatHERS climate data skewing the guidance given designers through the energy rating process toward building approval of dwellings. Generally, designs are being tuned to cooler times which no-one expects to see again for a century or more. We will, of course, include this advice (or your ongoing silence) in the next edition of ‘Exemplary Advances’ planned for dissemination early next week.

29 November 2024

We are keen to know that DCCEEW’s ‘final decision’ is with regard to this update.  Our target dissemination date for our December “Exemplary Advances” is the end of next week, although it may slip to the following Monday because of our focus on the Asia Pacific Solar Research Conference in Sydney 3-5 December (APSRC).  One of our presentations there “Enhancing Australia’s Weather and Climate Data for Energy System and Weather-proofing Simulations” could also be enhanced by news of DCCEEW’s intentions and/or actions.  I attach that peer-reviewed extended abstract for your information.  Perhaps you could convene the NatHERS TAC to consider this issue along with any others that have arisen since its last meeting.

In reaching your decision, you might also be paying attention to recent relevant research such as “Machine learning suggests climate and seasonal definitions should change under global warming” here.  Because of its reference to the potential utility of Machine Learning, I have also attached for your team’s attention, another peer-reviewed presentation to the APSRC called “Disaggregating Daily Precipitation Data 1990 to 2022 into Half-Hourly Intervals Using LSTM Models” relating our use of Machine Learning to enhance precipitation data between 1990 and when each location first began to employ tipping-bucket rain gauge recording.

We confirm that our offer to gift the current files to DCCEEW for use in the updated NatHERS rating software remains current.  And we look forward to your advice on what DCCEEW intends to do (or is doing) to keep the NatHERS software providing sound and currently relevant advice and design signals to the housing industry.

7 November 2024

We are keen to know what DCCEEW’s ‘final decision’ is with regard to this update.  Our target dissemination date for our December “Exemplary Advances” is the end of next week, although it may slip to the following Monday because of our focus on the Asia Pacific Solar Research Conference in Sydney 3-5 December (APSRC).  One of our presentations there “Enhancing Australia’s Weather and Climate Data for Energy System and Weather-proofing Simulations” could also be enhanced by news of DCCEEW’s intentions and/or actions.  I attach that peer-reviewed extended abstract for your information.  Perhaps you could convene the NatHERS TAC (Technical Advisory Committee) to consider this issue along with any others that have arisen since its last meeting.

In reaching your decision, you might also be paying attention to recent relevant research such as “Machine learning suggests climate and seasonal definitions should change under global warming” here.  Because of its reference to the potential utility of Machine Learning, I have also attached for your team’s attention, another peer-reviewed presentation to the APSRC called “Disaggregating Daily Precipitation Data 1990 to 2022 into Half-Hourly Intervals Using LSTM Models” relating our use of Machine Learning to enhance precipitation data between 1990 and when each location first began to employ tipping-bucket rain gauge recording (now accessible here).

We confirm that our offer to gift the current files to DCCEEW for use in the updated NatHERS rating software remains current.  And we look forward to your advice on what DCCEEW intends to do (or is doing) to keep the NatHERS software providing sound and currently relevant advice and design signals to the housing industry.

In 2024 August edition of Exemplary Advances, under the heading “60 New 34-Year Weather and Climate Data Sets now Available” where we were continuing our ongoing reporting of progress on our latest climate file production process, we also announced our offer to assist with the updating of NatHERS by providing our current climate files for their 69 climate zones (locations) and their 4 proposed additional sites as well. Here again is what we wrote.

“Given the seriously outdated climate files currently in use in NatHERS (and the corollary use of the same ‘climate’ in non-residential simulations) misleading designers and regulators alike, Exemplary Energy has recently offered to donate to the Department of Climate Change, Energy, the Environment and Water (DCCEEW) a full set of current climate files for use in any future update of those effectively mandated-by-regulation data sets.”

In response to a query from a team member of the NatHERS Administrator indicating that an update was desired, our offer was made formally on 4 September under the heading “Provision of Current Climate Files for NatHERS – Gratis” setting out our peer-reviewed expertise, our transparency of process and track record and allowing the NatHERS Administrator to select the time line for the input weather data and recommending our initiative of using only the last 15 years to best be indicative of the climate now. Given the cost saving and program acceleration that we were offering, we were disappointed by an initial rejection of our proposal and the stated intention to begin again with the process they have used in the past.  

It turns out that this was last done in 2020 when New Zealand’s National Institute of Water and Atmospheric Research Ltd (NIWA) using weather data to the end of 2019 but for some reason this work never found its way into the NatHERS software. Perhaps it was difficult to convince the Ministry of the Morrison Government that the climate was actually changing and that designing dwellings for past climate patterns would be skewing designs against the climates in which those buildings would actually operate, defeating the purpose for which the NatHERS scheme was developed.

Some negotiation has followed that initial rejection and at this stage, the latest we can report is the statement from DCCEEW’s Energy Performance and Security Division | Home Ratings and Disclosure Branch | NatHERS Tools and Technical Section on 4 September is:

“At this stage, the Department has not made a final decision to procure the necessary climate file updates but … any decision to do so will be undertaken strictly in accordance with the Commonwealth Procurement Rules established under the Public Governance, Performance and Accountability Act 2013.”

Accordingly, we have now notified Shadow Minister for Energy and Emissions Reduction, the Hon. Dan Tehan MP, of this gross waste and failure of internal process.

Mr. Tehan’s office has expressed interest in this matter and will be exploring it further, now that the Coalition’s downplayed attitude to emissions reductions has been settled. They remain committed to eliminating government waste.

The likely interest of the Australian National Audit Office (ANAO) and/or the National Anti-Corruption Commission (NACC) has also recently been raised with the Department and the Assistant Minister for Climate Change and Energy, Hon. Josh Wilson MP.

So far, DCCEEW has not advised us of any progress in updating the NatHERS climate files. We will update this situation in the next edition of “Exemplary Advances”.

Worldwide, as greenhouse gas emissions are still increasing and temperatures are rising across land and sea, the latest CSIRO and Bureau of Meteorology State of the Climate Report  highlights that Australia’s climate is also continuing to warm.

Australia’s land and seas are now at record levels of heat. On land, Australia has warmed by an average of 1.51°C since 1910 and our oceans have heated up by 1.08°C on average since 1900.

As Australia keeps warming, extreme heat events will become more frequent and more extreme: extreme fire weather occurs more frequently and is more intense; sea levels are rising; marine heatwaves are becoming more intense and frequent; and oceans are getting more acidic. All of these come with serious consequences for Australia’s environment and communities. Extreme heatwaves cause more deaths in this country than any other natural hazard, peaking at 830 heat-related deaths during Australia’s hottest year in 2019. Globally, 2023 was the hottest year on record to date.

Almost all (90%) of the extra heat trapped by greenhouse gases has gone into the oceans. Oceans are getting rapidly hotter. This matters because ocean heat strongly influences weather patterns in Australia. Australia’s oceans are warming faster than the global average, and the oceans off south-east Australia and the Tasman Sea are a particular hotspot and are now warming at twice the global average. As the seas warm, they expand. This thermal expansion is one of the main contributors to rising sea levels. Around Australia, sea levels have risen 22 centimetres since 1900 – with half of that since 1970.

Climate change is driving a major divergence in where rain falls in Australia. In northern Australia, average wet-season rainfall is now about 20% higher than 30 years ago, but in southwestern Australia, rainfall in the cooler, growing-season months has declined 16%, and in the southeast by 9% in recent decades. More rain in these regions now falls in heavy, short-lived rainfall events.

These changes are also reflected in our rivers, with significantly lower flows for about one third of the gauges in the south. Australia-wide, only 4% of our river gauges are measuring increased flows, and almost all of these are in the north.

For the world as a whole, 2024 will be world’s hottest year on record, EU scientists say

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Homes receive an Energy Efficiency Rating (EER)[1] based on the amount of energy required for cooling in summer and heating in winter to stay comfortable year-round, with higher star ratings indicating greater comfort and lower operational energy costs. We offer a ready-reckoner on our website to estimate the annual costs of gas and electricity for heating and cooling any dwelling – house, townhouse or apartment – of your chosen size. Additional energy costs for ducted systems are separately estimated on the basis of a single-storey house with ducts in its roof space.

Originally established for Canberra ACT (NCC Climate Zone 7), this has now been expanded to include all eight Australian capital cities. The calculations are based on current gas and electricity prices released in July 2024 specific to each location, and include the option of all-electric home conditioning.

Users are able to input a preferred home size between 75 and 500m² to compare the estimated energy costs of heating and cooling a home corresponding to an EER using appliances of varying energy rating. The matrix covers the following five NCC Climate Zones (CZ), and results are indicative of other locations in the same CZ (for example, Canberra values for Armidale NSW and Ballarat VIC in CZ 7):

CZ 1 – Hot Humid Summer, Warm Winter (Darwin)

CZ 2 – Warm Humid Summer, Mild Winter (Brisbane)

CZ 5 – Warm Temperate (Adelaide, Perth, Sydney)

CZ 6 – Mild Temperate (Melbourne)

CZ 7 – Cool Temperate (Canberra, Hobart)

WordPress Data Table Plugin

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[1] The latest changes to the National Construction Code (NCC) which took effect from 1 May 2024 include the introduction of a minimum 7-star energy efficiency rating for new homes, and a Whole of Home energy budget rating that considers energy use in a home from appliances and equipment.

[2] Underlying Assumptions include NatHERS standard occupant numbers and behaviours, NatHERS star-band energy index values in MJ/m² of heating and cooling combined, and climate-appropriate ratios of heating to cooling to apply appropriate fuels and appliance efficiencies to those combined values. For NCC CZs 2 and 5, these ratios are estimated from the BASIX tables for all NSW NatHERS climate zones on the basis of this source.