Benchmarking Philosophy

eTool recently changed from offering numerous fairly localised benchmark options to a single international average benchmark for each building type.  The decision making process was interesting so I thought I’d quickly document it.

The purpose of the eToolLCD benchmark is:

  • To establish a common measuring stick against which all projects are assessed so that any project can be comparable to another (for the same building type);
  • To create a starting point, or “average, business as usual case” from which to measure improvements.

From the outset we’ve always understood that a benchmark needs to be function specific.  That is, there needs to be a residential benchmark for measuring residential buildings against etc.  The first point essentially addresses this.

The second point introduces some complexity.  What is, or should be, “average, business as usual”?  More specifically, are people interested in understanding how their building performs when compared compared locally, regionally, nationally, or internationally?

When we started trying to answer this question, some scenarios were very helpful.  If a designer wants to compare locally, the benchmark needs to reflect the things that are most important to the overall LCA results.  The two most critical things are probably electricity grid and climate zone.  Localising just these two inputs gets pretty tricky and the number of possible benchmark permutations starts to add up pretty quickly.  In Australia there are four main independent electricity grids (NEM, SWIS, NWIS and Darwin).  In the Building Code of Australia there’s 10 climate zones.  Accounting for which climate zones occur within each grid, there’s about 20 different benchmarks required.  To add to the complexity though, the NEM is split into different states (New South Wales, Victoria, Australian Capital Territory, Queensland, Tasmania and South Australia).  Generally, because the National Greenhouse and Energy Reporting guidance splits the NEM into different states, the NEM is usually considered as six different grids. So there’s upwards of 50 different benchmarks we’d need to create and maintain for Australia alone just to localise electricity grids and climate zone.

One disadvantage of this method is it’s still not all-accommodating.  It doesn’t account for remote grids of which there are many in Australia.  An example is Kunnanurra which is 100% hydro power.  So even in this scenario where we had 50 or so benchmarks for Australia, there’s still big potential for a designer patting themselves on the back for a great comparison to the benchmark when really it’s just a local condition, and vice versa.  The same can be said about an off grid scenario (effectively just a micro grid of it’s own).

The other disadvantage is maintenance of all these benchmarks.  Expanding the above scenario internationally there could easily be 1000’s of possible benchmarks.  There’s so many that it would be hard for eTool to initially create them, and even harder to subsequently maintain them.  Clearly the localised benchmark option had some big challenges.

At the other end of the benchmarking philosophy we considered just having generic benchmarks, or even one global benchmark.  This is perhaps a more user-centric, or building occupant sensitive system.  That is, the building occupants are probably more interested in this measure as it’s more about how they live compared to the global community.  So a building may be “average” compared to the local context, but actually be very low impact compared to the broader average (due to favourable local conditions).  Conceivably, the local conditions contributing to the ease with which a building can perform may be part of people’s motivation for living in a particular area.

The disadvantage of the generic benchmarking approach is that it isn’t as useful for a designer to compare their building’s performance against this as the local conditions (which may create a significant advantage of disadvantage) aren’t considered.  This was a big consideration for us, eToolLCD is a design tool, it has to be relevant to designers.  Interestingly though, the way eToolLCD is generally used is the base design is modelled, and then improvements are identified against this base design.  The benchmark is usually only used towards the end of the process as a communication and marketing tool.

Also, there’s no reason why the designer can’t model their own local benchmark, for example, a code compliant version of their own design.

This topic spurred some serious debate at eTool.  In the end, the deciding factors were:

  • A local approach couldn’t really be adopted without localising at least the grid and climate zone for each benchmark option.  That is, it would have been too difficult to go half way with localisation (for example, only localising climate zone and not grid), as this really just revoked the whole advantage of localising the benchmarks.
  • Taking the very localised approach was going to put a huge benchmark creation and maintenance burden on eTool which wasn’t necessarily productive
  • The choice of a generic benchmark didn’t detract from the function of eToolLCD as a design tool.
  • Greenhouse Gas pollution is a global problem not a local problem, we feel people probably need to measure and improve their performance against a global benchmark rather than a local one.

So the single global benchmark was the direction we choose.  Once this decision was made, we needed to determine how to statistically represent global averages.  We decided to choose an aspirational mix of countries to make up the global benchmark, that is, select the standard of living that we felt most people in the world aspire to and determine the average environmental impacts of buildings in these demographic locations.   This does mean the global benchmarks are generally higher than the actual global average building stock for a given function.  That doesn’t stop us from estimating what the sustainable level of GHG savings is against this aspirational benchmark (90%+).  It also enables us to strive for this level of savings without adversely effecting our standard of living aspirations (globally).  The global benchmark created using this approach is the residential benchmark.  More information about how this was conducted can be found here.

For those people or organisations that would like a customised benchmark, eTool can provide this service.  Please get in touch.

Brown Paper Background

eTool International Residential Benchmark (Methodology Summary)

Below is a summary of our approach to the International residential benchmark.  A full EN15978 report on the benchmark model can be found here.  International Residential Benchmark Weighted x10 dwellings v28

In light of eTool’s recent exploration into global markets, we thought it prudent to create a “global” benchmark for housing developments.  eTool will be using this benchmark for all future housing projects. The reasons an international statistically mixed use benchmark is the most robust model to compare designs against are as follows:

  • The planet does not care what kind of house you build only how close it is to zero carbon. A mixed use benchmark provides a fair comparison of performance across different house types be it apartments, detached, maisonettes etc.
  • The planet does not care where you build your building, only how close it gets to zero carbon. Climate change is a global problem, whilst regional benchmarks can be useful for comparing similar buildings in the same area they can produce unfair results.  For example, a house built in a low carbon grid area (e.g. Brazil) may have emissions of 2 ton/person/year.  This may only be a small improvement against the average Brazil house as they both have the benefit of a low carbon grid.  Conversely a building in WA may have higher emissions (say 3 ton/person/year)  but despite having higher emissions than the Brazil case could show a larger improvement against the average WA house.  A single benchmark is the only way to give correct credit for the true sustainability performance of a building.

Before getting into the nitty gritty, it’s important to understand the purpose of the eTool benchmark, which is:

  • To establish a common measuring stick against which all projects are assessed so that any project can be comparable to another.
  • To create a starting point, or “average, business as usual case” from which to measure improvements.

Benchmark Form and Structure

The benchmark has been created to represent an average dwelling built in a developed country, the statistics for a range of developed countries have been population weighted and combined into a single theoretical average dwelling.


The statistics used in the benchmark are based on data obtained for each country. The construction type and dwelling size statistics take new build data wherever available, as this data is generally reliable and represents a picture of the way buildings are currently being built across the developed world. For residential buildings there is a mix of houses and apartments. This is the latest breakdown of the new dwellings density mix across the countries considered in 2010:


The occupancy is calculated by dividing teh countries population by the number of dwellings to give an average. This is weighted by population to give a global average of 2.52.
For the single dwelling element (59% of our average dwelling) a building structure has been modelled taking a cross section of commonly used construction techniques. In this instance, the data was obtained for U.S.A.  The U.S.A makes up the largest proportion of new housing in the developed world and is considered to represent a fair “average house.”  Construction techniques are unlikely to differ significantly enough to impact on the overall modelling, whilst brick houses may be more common in the U.K. and Germany, timber framing is far more prevalent in Japan and Sweden.


A similar approach was taken with windows, internal walls, floors and roofs. The vast majority of those installed in new builds across America and Europe are double glazed and allowances have also been made for the smaller proportions of other window framing options currently in common use.


For the multi-family dwellings, a standard concrete frame structure has been taken with one level of car parking and typical auxiliary and common layouts, such that the apartment living area represents approximately 50% of the total floor area of the building.  The total impacts of this building have been weighted on a per m2 basis and 56 m2 has been added to the model to represent the apartment element.

Benchmark Operational

Existing data has been used for operational energy, and arguably new build data would be preferable, but total existing data is generally a lot more robust (and readily available). Whilst new build energy figures were available for some countries, the figures tend to be from modelling completed for regulatory purposes and are therefore theoretical. In many countries there is a perceived “performance gap” between modelling results and actual consumption mainly due to differences in occupant behaviour, but also because of limitations in software and methodologies used for the modelling. The hope is that there will be continued industry effort towards monitoring of new build housing performances. Until further data in this area is available, we have a robust snapshot of how average buildings are currently performing by taking existing housing data.

The data for total residential fuel consumption was divided by the total number of dwellings in each country analysed. This was then weighted according to population to give a final figure for the average energy consumption of a developed country dwelling.


End-use percentage estimates were then used to determine where this energy is being used in the dwellings.  Again, U.S. data[ix] has been used to represent the average.


Other impacts such as appliances and cabinetry and finishes have also been included by the estimated proportion of dwellings estimated to include these.

The global average water consumption is considered fairly consistent across most developed countries with America and Australia having higher water consumption due to larger garden sizes.  A conservative nominal 169l/person/day has been assumed for water supply and treatment.


[i] Populations by country 2010

[ii] Characteristics of New Housing U.S.A

[iii] Statistics Bureau Japan

[iv] EU Odysee Data 2008 downloaded on 11.7.2014

[v] Australian Bureau of Statistics Average floor area of new residential dwellings 2012

[vi] U.S. Energy Information Administration – Annual Energy Outlook 2014 – Energy Consumption by Sector and Source,ref2014-d102413a

[vii] Odysee energy database for EU and Norway (2008) downloaded from in July 2014

[viii] Statistics Bureau Japan Chapter 10 Energy and Water

[ix] U.S. Energy Information Administration Residential Sector Key Indicators and Consumption,ref2014-d102413a




eTool LCA Software Updates – Autumn 2014

eTool LCA for Any Project

We conducted a retrospective LCA on the harbour bridge a while back, which highlighted how versatile eTool LCA was.  It was clunky though.  Whilst setting up the harbour bridge project we had to answer questions in the eTool LCA interface like “Number of bedrooms”.  We weren’t quite sure how we were going to solve this little quandary once and for all.  There seemed to be an unmanageably large number of different types of structures with potentially unique functional attributes.  For example, in the OmniClass classification there’s 748 different “Facility Types”.  When you also add all the possible iterations of mixed type facilities we really started scratching our heads.  Why?  Here’s a few reasons:

  • The result was bigger than the biggest number that excel could calculate (1.79 x 10308)
  • If we provided the software uses with a drop down to choose from this list, the drop down would extend past he bottom of your screen, through the Earth, out of our solar system, out of the milky way and through a bunch of other galaxies.
  • If you could navigate through that list of different functions at the speed of light, and the one you wanted happened to be half way down the list, it would take you longer than the time between the big bang and now
  • The amount of data stored in that list would take your computer about the same length of time to retrieve the list from the internet

Anyway, we knew we needed another method.  We needed an ability to not only choose from the list of facility types, but enable custom combinations of these facility types in the one design.  For example, a mixed development with residential, retail and commercial space.

This feature also started us on our journey of BIM integration.  Thus far we’ve drawn on COBIE as our categorisation standard, but in the future we hope to map this to other standards so users can report however they see fit.  The flexibility of eTool LCA just exploded (without the clunkiness, or waiting until the next big bang for your list of facility types to download).

eTool LCA for Infrastructure

In our new list of possible design functions we have infrastructure elements such as roads, rail, air ports, bridges, stadiums etc.  We even have applicable functional attributes that users can choose for the appropriate infrastructure.  For example, a road designer may choose to measure their impacts per:

  • passenger transported
  • tonne of freight transported
  • workload unit (one passenger or 100kg of freight)
  • unit area of pavement
  • unit length of the road

Hopefully this drives some serious though about what the function of that infrastructure is, and how the movement of passengers or freight may be better done with lower carbon alternatives such as rail!  After all this is one of the beauties of LCA.

eTool LCA for Energy Generators

Another neat example of facilities that can now be assessed with eTool LCA is electricity generators.  Fancy running an environmental life cycle assessment of a wind turbine verse solar PV verses coal fired plant?  Knock your socks off!  The functional unit you’ll probably be choosing here is impacts per life cycle kWh generated.

eTool LCA for Data Centres

A little left field, but how to you compare the sustainability of data centres?  Have a go in eTool LCA!  You can choose from the below functional units to ensure you’re making fair comparisons between different options:

  • Annual data stored
  • Life cycle data stored
  • Annual data transmitted
  • Life cycle data transmitted
  • Net usable area

What next for eTool LCA?

For those who are rushing to check out the above functionality, bare in mind this is hot off the press and we’re yet to develop a library of templates that support these new types of construction entities.  This will come though, especially with the template validation functionality that is already helping our library grow.

In the mean time, software features continue to roll on.  The two big projects we’re working on at the moment is BRE IMPACT compliance.  We’re excited about this as it’s a third party verification system specifically designed for what eTool LCA does – LCA of Construction Projects.  Not only is this a big indication of the mainstreaming of LCA, it’ll also be really nice to have an official seal of approval on the accuracy of eTool LCA.

The other big project is a push on reporting.  We’re introducing a whole heap of cool new reports aimed at users to generate promotional and marketing ideas for their improved buildings.  Is this core to LCA, absolutely now.  Is it important to ensure that environmentally sustainable buildings proliferate?  Absolutely.  We don’t have our pulse on this globally but we hazard to guess the biggest impediment to truly sustainable buildings in Australia is a total disinterest within the real estate industry.  And eTool LCA is will hopefully spark this interest a little more by providing agents with really useful info to help them sell better buildings.

Past that, refer to our product roadmap which (although partially implemented) gives a good idea of where we’re heading longer term.


eTool LCA Software Updates – Summer 2014

EN15978 Compliance

The last few months have been hectic for our software development team. We brought the software into line with the European standard EN15978 – Sustainability of construction works – Assessment of environmental performance of buildings – Calculation method.  We undertook so eTool could be used to gain innovation credits in Green Star projects.  For out international audience, this is a environmental rating scheme managed by the Green Building Council of Australia.

Technically the update was a big challenge, EN15978 a very comprehensive standard with quite strict rules regarding how the LCA calculations should be conducted.  It’s a piece of work we planned back in 2012, we did need that little commercial push to undertake the change, and the opportunity to utilise eTool LCA for Green Star projects provided this.  We are really happy that we managed to complete this piece of work.  We really think the planet has a lot to benefit from through this standard, and hopefully through the use of eTool LCA.  Here’s some reasons:

  • EN15978 was written by CEN technical committee 350 who are also developing other standards to meet there overall mandate of delivering standards to holistically assess the sustainability of construction works.  This is really exciting.  It effectively draws a line in the sand and gives really solid guidance on how we should be assessing the buildings.  It includes social, economic and environmental considerations for sustainability.
  • A good Life Cycle Assessment is without doubt the best way to measure and improve the environmental performance of something.  This has been recognised by CEN TC 350 who have relied on it nearly exclusively for the environmental assessment of buildings.
  • CEN TC 350 also developed a standard for the assessment of building products.  These will be used by the new ECO EPD framework being developed in Europe which will align most of the major EPD Program operators.  Now this is exciting.  Finally, we have an international system that reports truly comparable data for construction products.  It’s equivalent to nutrition labelling for building products (substituting health info with environmental info).

All this means the stars are nicely aligning for low impact buildings.  There’s a huge opportunity to cut through the greenwash if industry uptakes this approach.  One of the things we love about this approach is it actually enables policy makers to set budgets in order to ensure we hit sustainability goals.  I’ve written about this concept and how it might be approached here.

Software Speed Improvements

Users during the last 12 months would have noticed that at times, particularly for very big designs, the software laboured.  It was getting pretty frustrating for our ops team who were working more and more on complex LCA models for large projects.  We’d delayed tackling this problem because it required a massive re-write of the back end.  There’s nothing worse than spending two months labouring on a software improvement project, then delivering the result which looks exactly the same!  It was a very nice change though, to give you an idea of the performance improvement, we had a large test design that was taking the best part of four minutes to save, now it’s taking just two seconds.  The big driver for this was actually to enable more features to be introduced to eTool LCA that would have otherwise slowed it down further.  There’s more coming!

Record Recommendations

This is probably  my favourite new feature.  It makes the job if modelling and tracking improvement ideas very easy.  I can honestly say this has enabled our operations team to significantly increase the research time we can allocate to identifying more improvement ideas.  Less time doing little admin tasks like copying and pasting data between eTool and spreadsheets, and more time focusing on reducing the impacts of the design.  All users need to do now is hit record, model the improvements, hit stop and every change to an impact due to that improvement will be recorded at different life cycle stages of the building.  And it’s recorded for every indicator too, so you can see how much carbon you saved verses how much money you saved.   I love using this feature.  Check it out.

EN 15978 and eTool LCA Normal System Boundary

EN 15978

In 2011 the European Committee for Standardisation (CEN) released a new standard for measuring the environmental sustainability of buildings.  We grabbed a copy of this standard, EN 15978 soon after it was published to understand how eTool stacked up against the requirements.  We breathed a sigh of relief, although we had a few things to tidy up, what we were happy with was that we actually needed to reduce the scope and system boundary of a normal eToolLCA to report to EN15978.

Background to EN15978

This standard was one of the first to be released by CEN Technical Committee 350.  It was part of a much broader project to fully define how to measure the sustainability of buildings.  Within TC 350 there were working groups determining how to measure a building’s:

  • Environmental Performance,
  • Social Performance, and
  • Economic Performance.

Impressive.  The full suite of sustainability covered under one set group of standards.  And it doesn’t stop there, there are also working groups covering civil works and construction products.  Incredibly, they are making very good headway through this arduous scope with 8 standards already published and another four under development.  EN15978 is the key to measuring the environmental pillar of sustainability.

How Does it Work?

Well, it’s kind of complex you have to read the detail of the standard, and a good number of the standards referenced.  That said, we will summarise as best we can.  The basic philosophy is to rely 100% on LCA as the method of measuring environmental performance.  So there is hence a heavy reliance on ISO 14040, 14044 and 14025 which eTool LCA software also heavily draws on.  The standard gives guidance on how to apply LCA to buildings.  It effectively defines the goal, scope and method for LCA practitioners working on buildings.

The System Boundary

The diagram below shows the system boundary of EN 15978 is shown below.  For existing users of eTool LCA, or those who rely on eTool ratings, our standard system boundary is also shown.  We think the EN 15978 have essentially done a fantastic job putting this together (with a few exceptions we discuss below).

EN 15978 and eTool LCA Normal System Boundary

EN 15978 and eTool LCA Normal System Boundary

The largest omission from the system boundary is what EN15978 calls “non building related energy use”.  They essentially include HVAC, domestic hot water and lighting but exclude all other energy used within the building.  This makes sense at first glance, after all, these areas are certainly the most heavily influenced by the building designers, and other energy use is very heavily occupant driven.  There are however some strong arguments for including all energy used within the building, a few of which are listed below:

  • A building designer can influence occupant behaviour, and as such these aspects should be considered by architects and engineers, for example:
    • Energy monitoring has been proven to influence occupant behaviour in both commercial and residential buildings and should be considered by the design team
    • In residential buildings, energy use per occupant generally drops off with higher occupants per dwellings due to the base loads (refrigeration, living area entertainment, standby loads, lighting and heat losses from hot water systems) being spread between more occupants.  Buildings that allow and encourage more occupants per dwelling will (all else being equal) use less energy per occupant, and hence should be differentiated.
    • In commercial buildings, an integrated fit out of work stations can have huge positive impacts on energy use through the use of central servers for data storage and processing and mini computers at work stations drawing very little power.  A seamless implementation of such systems may require architectural and engineering consideration during the design of the building so should be factored.
  • Building integrated renewable energy systems should if possible be sized to meet the entire load of the building, not just the base building loads, so designers should be aware of the entire loads.
  • Developers can have a large influence on the building performance (at least initially) through the final fit out of appliances (residential) and work stations (commercial) so this should be within scope so we don’t drop the ball on this opportunity.
  • Vertical transport (elevators, escalators etc) for medium rise buildings can be heavily influenced by design:
    • The building envelope needs to cater for the most efficient plant geometrically
    • The use of stairs or ramps should be encouraged through design to reduce reliance on plant
    • The building electrical systems should be designed to cater for regenerative drives etc
  • Communicating the total impact of buildings without accounting for occupant energy use is very misleading.  Imagine moving into a building marketed as ‘energy neutral’ building only to find your power bill only drops 25%

Environmental Indicators

The suggested list of reported indicators is quite comprehensive for EN15978 and is shown in the below summary table:

 EN15978 Indicators

EN15978 does state that not all indicators need to be reported, but the documentation must specify the reasons for omission.  Interestingly toxicity, land use, biodiversity are missing from the above list.  The standard states that this is due to there being no scientifically agreed calculation method within the context of LCA for these indicators.  We’ll watch this space as we know some of these missing indicators are of great interest to many users of eTool.

EN 15978 and eTool LCA

After we read EN15978, we documented the required changes, pushed them into our product roadmap we got back to other work.  It wasn’t for another year though before it hit us how important this standard was.  All of a sudden, we weren’t “those guys from Western Australia who think they’ve nutted out how to truly improve the environmental performance of buildings”, EN15978 established that LCA was indeed the most appropriate tool for profiling green buildings.  Standards such as this one lend huge credibility to solutions like eTool that were released prior to the standard.  We were definitely barking up the right tree when we naively stood in front of the cameras on the ABC’s New Inventors and demonstrated the humble beginnings of eTool!

The recent uptake of LCA by the Green Building Council of Australia in their Greenstar tool heavily references  EN15978.  This has prompted us to build a suite of reports that are compliant with the standard, and those it references.  Importantly, we’re not going to remove any functionality form eTool, or contract the scope or system boundary.  Users will simply have the opportunity to report to either the EN15978 scope or the more expansive eTool LCA scope.  Similarly we’ll continue to upload more indicators into eTool LCA, our focus for the next 12 months will be plugging the gaps for EN15978 reporting.  There’s likely to be a lot of low hanging fruit here, and some trickier ones that may take some additional programming so we’re not entirely sure when we’ll be reporting on all 22 indicators just yet.  Our reports will be compliant with EN15978 though by still listing these additional indicators with “INA” (Indicator Not Assessed) in place of the calculated values which is accepted in the standard.  We’ll also allow users to report indicators currently available in eTool that aren’t required by EN15978.  Our general position on indicators is that global warming is our biggest environmental problem and hence our main efforts will continue to focus on solving this.

LCA_Alex home_basic design

eTool and Internet Explorer

We’re pushing the envelope a little with what’s possible for web based software and Microsoft Internet Explorer has been a pretty challenging for us, it seems that we fix it up to work in one version, and those fixes break something in another version.  Needless to say, if you’re happy using safari, chrome, firefox or basically any other browser by MS Internet Explorer you shouldn’t have any issues.  If you’re stuck with MS IE, or love using it, here’s the work around for using the eTool app…


eTool LCA Software Updates – Spring 2013

eTool is always busy in the background updating the libraries available to users.  Lately we’ve ramped up the activities in a big with with some major updates to our libraries.  Even more exciting is that we’re improving the functionality of eTool with some big software development projects.  I thought I’d take some time to update you.

Library Updates

Earlier in the year we conducted a large LCA study on a cutting edge development in the UK, One Brighton.  The study was commissioned by Bio Regional who run the One Planet Living sustainable living framework.  We will be publishing the results of this study before the end of the year.  During the modelling we adapted a pretty cool approach to modelling the UK Benchmarks where we morphed a number of different density buildings, based on the new build mix, to create a weighted average density and size building.  Our previous approach to this was to pick the most popular density building and adjust it’s size and other characteristics appropriately.  We liked the new approach so have also applied that to Australia.  This was timely as the density mix in Australia is also changing pretty dramatically as we embrace higher density living, particularly in Sydney and Melbourne (Sydney is now building more apartments and semi-detached dwellings than detached).  The new residential benchmarks are loaded up into the eTool Library read to compare your project against.  We’re also working on some office building benchmarks also, and looking into community buildings.  Watch this space!

Out templates library is also undergoing a bit of an overhaul.  There’s more to come but essentially we’ve be consolidating the current templates library and adding new templates where needed.  This will be an eternally evolving project and we have some really cool ideas about how users can share templates that we’re mocking up at the moment with implementation in mind.

Our materials, transport, equipment and energy databases are about to get an overhaul to.  You may have heard the GBCA has introduced credits for LCA.  Some of the indicators they’ve chosen weren’t being tracked by eTool so we’re in the process of updating this data.  Some interim updates have been performed including updating electricity grid coefficients to match the latest NGERs figures in Australia, and updates to some water grid figures (notably Perth to account for the increasing reliance on desalination).

Software Updates

Some big projects are now underway to take the eTool software to the next level.  See our product road map to get an understanding of the long term goals.  The focus is on aligning eTool with relevant international standards (in particular EN15978).  In the process we’re also fixing bugs along the way and generally improving the user experience.  Recent or impending improvements are listed below.


Improved speed for the app.  You may have noticed that working on large designs the app started to labour a bit, or a lot if you were working on really big designs.  We’ve cut the save / clone time down by 75% which although is a good start is just the tip of the iceberg, we’re aiming to get a 95% improvement in performance in speed through a project that is revolutionising the back end of eTool.  I won’t go into the details, I’ll just say it’s a big project but is going to pay big dividends to users.

We’ve also changed the UI a little. Projects will soon be listed more conveniently (most recent on the top of the list when you log in).  There’s a big expansion in functionality for documenting project recommendations and our reports are about to get some serious attention also.

Bug Fixes

A few pesky bugs have also been fixed:

  • All design details now clone properly
  • Custom template details now clone properly
  • Reports on a design can be seen by all users accessing that design
  • Updates to certificate calculations to include PV generation and limit overall rating when gold savings aren’t achieved in both embodied and operational categories


Brown Paper Background

eTool Residential Benchmark For Australia

Before getting into the nitty gritty, it’s important to understand the purpose of the eTool benchmarks, which is:

  • Establish a common measuring stick against which all projects are assessed so that any report is comparable to another (for the same type of project).
  • Create a starting point, or “average, business as usual case” from which to measure improvements.

The benchmarks are not an average of existing stock but rather an average of new stock. Hence any efficiency requirements etc in the Building Codes etc are taken into account. When comparing to the benchmark, the target is pretty simple. Effectively Australia has to drop it’s GHG emissions by about 90-95% on a per capita basis for us to become sustainable global citizens. With this in mind, what we should be trying to do is drop our building’s emissions by 95% against the benchmark to ensure the building is stabilising the climate.

Creating the business as usual benchmark is pretty complex. For residential buildings in Australia there is a broad density mix from detached through to apartments. This is the latest breakdown of the new dwellings density mix in Australia (from ABS) over the last two years:

DetachedSemi DetachedLow Rise ApartmentsHigh Rise Apartments
Proportion of New Dwellings61%13%7%19%

For each of these density types, eTool have formulated a BCA code compliant building. We have then created a nominal statistical mix of  floor areas to match the average new dwelling size in Australia (214m2). In this way we come up with a “dwelling” that is a mix of densities and matches the size of the average Australian dwelling.

A similar approach is taken for operational energy. In this case we first research the most up to date residential energy estimates for Australia.  This data comes from ABARE Energy in Australia 2012. It gives us guidance on the total energy used per household (existing housing stock) in Australia and also the fuel mix split (electricity, gas, wood etc). We then use other end use percentage estimates to determine where this energy is being used in the dwellings.  The most commonly quoted breakdown of household energy use in Australia is from the “Your Home Technical Manual” which is actually a reference to the “Energy Use in the Australian Residential Sector, 2008”.  This report is commonly referred to as the “Base line report”.  This report itself actually states:

The study identified a paucity of end-use data for residential energy use in Australia, particularly in regional areas. Some of the appliance energy consumption estimates used in this study rely on research that is 15 years old or, alternatively, on work undertaken in New Zealand. 

The study recommends an comprehensive end use energy monitoring program which we believe is being undertaken. Until the results are out we’re a feeling our way in the dark a little.  Not withstanding this, the study is useful to guide the decisions about where we’re using our energy. To verify the Base Line Report figures we also took some state government studies (eg Sustainable Energy Development Office in WA) and statistics from other countries (notably the BRANZ HEET study and also stats from the US). The largest unexplained discrepancy seems to be in the estimates for heating demand.

The Base Line Report suggests that 38% of total end use energy in Australia homes is dedicated to heating and cooling purposes.  This seems very high given the following facts:

  • The comprehensive HEET study from BRANZ in New Zealand (a much colder climate, and one dominated by heating requirements) only calculated 34% of end use energy dedicated to thermal performance.
  • The WA SEDO estimate for thermal comfort energy demand is also much less, hence it’s hard to believe the additional demand is due to cooling.
  • A large percentage of Australia’s population (Perth, Sydney and Brisbane) all live in quite mild or warm climates where heating would not make up more than 50% of the thermal control energy demand (and less still of the actual end use energy demand)
  • Heating is the most end use energy intensive thermal comfort mode as cooling typically utilises either apparent cooling methods (evaporative or fans) or heat pumps, both of which have effective Coefficient’s of Performance of 2.5 or more. This means for every one unit of energy input, 2.5 units (or more) of heat is dissipated of pumped from the dwelling when cooling. Heating on the other hand requires more energy than the actual heat load demand theoretically required to heat a space (or at least the same amount). This is mainly due to flue losses.

The high estimate in the Base Line Report may be linked back to the ABARE Energy stats which are also questionable. The Energy in Australia 2012 document from ABARE gives a biomass figure for residential energy use that equates to 6280MJ / household /annum.  When this is calculated in terms of mass of wood, it works out at 400kg of timber per household in Australia.  Even if one in every 5 houses (studies suggest it’s more like one in every 10) is using a wood heater that was their primary source of heat, that’s 2t of wood per annum they would need to be burning in order for the ABARE data to reconcile. To give you an idea, an average small box trailer full of wood is about 250kg. We’re not convinced there’s 2 million households in Australia receiving 8 trailers of wood per annum to heat their homes. The BRANZ HEET study further supports the proposition that ABARE have overestimated biomass consumption in the Australian residential sector.  BRANZ calculated that each wood heater uses 4,500kWh (one tonne) of wood per annum.

Without making any adjustments to either the end use demand figures, or the top down supply figures the numbers don’t reconcile very well. For example, trying to “fit” the biomass, gas and LPG energy into the end use break down “squeezes” electricity out of the hot water and space heating categories. There simply isn’t enough low grade heat requirements in dwellings to account for all the biomass. However, when we aligned the biomass use predictions with BRANZ, and adjusted the demand figures to better match some of the competing studies we got good reconciliation.

This also supports the total residential demand estimate in the Base Line Report which is quite a bit lower than the ABARE stats.

Once we knew the amount of energy the existing housing stock were using, we then determine how this would differ in new dwellings.  Some energy use would remain pretty static (eg appliance use and refrigeration). Lighting, hot water and heating and cooling have relatively new BCA code requirements focussed on energy efficiency. For these end categories appropriate adjustments were made to account for the newer technologies and associated demand.

Heating and Cooling (Thermal Control)

The heating and cooling energy requirements are the most complex, as there are very few stats on what equipment is being deployed in new houses. The NatHERS system does help this situation and we make an estimate of the deployment of heating and cooling technologies in the current housing stock as follows:

  1. Estimate the heating verse cooling loads for buildings in the top 20 populous NatHERs climate zones (85% of Australia’s population). This works out to be 60% heating and 40% cooling.  
  2. Estimate the efficiency of each type of heating and cooling technology
  3. Estimate the deployment of each type of heating and cooling technology
  4. Adjust estimates such that total energy consumption matches our adjusted ABARE figures and the split in thermal demand matches the NatHERs weighted average for Australia

This then informs our decisions about what people are likely to choose for new houses.  The summary is found in the following tables:

Electric Heat PumpElectric Fans or Evaporative Coolers
Existing Stock Cooling Demand50%50%
New Housing Stock Cooling Demand60%40%

Electric Heat PumpElectric RadiatorsGas FluedGas Internal HeaterWood Heaters
Existing Stock Heating Demand20%10%17%51%2%
New Housing Stock Heating Demand35%0%20%40%5%

For each major BCA climate zone or population centre then simply divide the NatHERs energy demand estimates for a 6 star dwelling for the building between these categories and apply appropriate efficiency or COP figures to determine what the end use energy demand will be.

Hot Water

The building codes have now banned the use of electric resistance storage hot water systems in all residential buildings apart from class 2 building (strata buildings). Some state governments also discourage the use of electric heaters in class 2 buildings. This has led to a huge shift from electric storage hot water heaters to gas, solar, and heat pump units. This is a great thing for reducing the carbon intensity of the delivered hot water to dwellings (see more explanation on hot water fuel types here).

Using the same reconciling procedure between the end use energy estimates and the adjusted ABARE data we get the following mix of fuel uses for meeting demand in Australian existing housing stock:

Fuel Contribution to Water Heating Demand of Existing StockFuel Contribution to Assumed Water Heating Demand of New Stock
Natural Gas and LPG77%79%

Note, this doesn’t imply that 77% of water heaters are gas fired, it implies that 77% of energy used by water heaters is gas. The difference is that gas water heaters have lower efficiencies than electric resistance heaters (99%) or heat pumps (approximately 270%). With a gas water heater, depending on the age of the heater, it may be as low as 50%, and won’t get much better than 85%. So the mix of heaters installed in existing buildings is actually more slanted towards electric.

New buildings will tend more towards gas due to the current BCA requirements. With this in mind, we’ve used the figures in the right hand column for the split in fuel use for new dwellings.


eTool LCA Software Updates – Autumn 2013

eTool LCA has been getting a bit of attention lately, and there’s some changes in the wind so we thought we would update everyone. An update on updates! Most of the recent changes have been updates to our libraries which are now getting pretty extensive.

New Electricity Grids

We’ve added a number of new electricity grids to our library to extend the reach of eTool LCA. The data was gained from public information which varied in quality, however where there was a discrepancy between reported direct emissions CO2 intensity, the fuel mix was updated to ensure consistency. Transmission and distribution losses are also accounted for for each individual grid, and upstream emissions associated with provision of fuels to power plants etc.

  • Ten new US grids including: Alaska, Florida, Hawai, Midwest RO, Mid East States, Northeast PCC, South East States, South West PP, Texas and Western ECC.  
  • Thirteen new European grids including: UK, Germany, France, Italy, Spain, Sweden, Finland, Denmark, Poland, Netherlands, Belgium, Czech Republic, Austria, Romania

At present in eTool software for life cycle cost calculations the electricity prices are linked to a grid, in development we are going to split this so that each grid can have a number of tariffs. We’ll also be introducing some functionality that enables a default grid to be selected at the project level to avoid the painful process of updating the grids after an operational energy template has been added.

New Water Grids

With the introduction of fresh water use as an indicator in eTool LCA, users now have the ability to calculate and compare the water footprints of their designs (embodied and operational). Further to this, the other impacts associated with water supply (take energy and CO2e to pump and treat water) are automatically calculated for users that add water use to the mix. The labelling of the “Demand” column in the operational energy section of eTool LCA is very clunky at the moment (the units state MJ or kL as we’ve got both energy use and water use in the same list) and we plan to separate this out into a new section on the design home page. In the meantime though, we’re excited about the ability to measure impacts associated with water supply and treatment and as of July 1st 2013 these impacts will be included in the standard eTool LCA scope. We’ve run some testing and there are some significant changes to the life cycle impact assessments results (particularly residential).

New Materials

Our LCA of One Brighton for BioRegional in the UK prompted a bit of an overhaul of our materials database, we’ve added a number of new material categories and individual materials (about 100 in total so too many to list). These new updates were a mix of generic LCA data (for example, much more granularity in blast furnace slag and fly ash concrete mixes) and EPD data. We’re happy to say that adding the EPD data was pretty straightforward and we’re now well and truly open for business for materials manufacturers who want to add materials to the eTool LCA database. Our stance on data quality at the moment is that as long ast he EPD has been registered with a reputable EPD program operator we will likely enter it into eTool software.  Longer term, once Europe releases the product category rules for the EcoEPD project, this is likely the methodology we will adopt. At that point we’ll give materials suppliers a 12 month grace period to update their data sets to match this standard.

Upcoming Changes:

As of 1st July 2013 we’ll be changing the way we account for a few things in eTool LCA. These changes are to ensure the decisions being driven by eTool LCA are robust. After all, it’s always been our goal that eTool LCA is used as early in the design phase as possible to make positive changes to designs, we don’t want it to be post mortem that just highlights lost opportunities!

The most significant changes will be the forward counting of electricity grid intensity figures. At present eTool LCA assumes the grids will maintain their current mix of fuels for the life of the buildings which is a very pessimistic forecast for the planet. Potentially in an LCA on buildings drawing from fossil fuel dominated electricity grids, this puts perhaps too much emphasis on reducing the use of electricity at the expense of increased gas use or additional embodied impacts. For this reason we’re going to account for depreciating fossil fuel.

Want to give eTool LCA a go? Register for your free account today!

eTool V2 Part 1 Complete

Our first step of course was to prioritise the improvements which was quite a task. Although we would love to press the magic button and fulfil the “holy grail” of sustainable design (3D optimisation of thermal performance and embodied impacts of materials) baby steps are required.

We asked you guys what you wanted to see; surveys went out to past clients who we have conducted LCAs for, and also our users (who are growing in number and geographical diversity every day).

The key enhancements that people flagged for us were:

  • More reporting functionality (particularly involving costs)
  • More environmental indicators (not just carbon and energy use)
  • More transparent user interface (simpler, clearer)
  • More templates, materials and equipment options in our libraries

So this is where we’ve been focussing our efforts.
If you log into eTool V2, you’ll see many features aimed at tackling the above key enhancements, and we’re not done yet! We will be continuing development on V2 until September.

Here’s a quick summary of what’s been implemented:

  • A better materials categorisation system and over 50 new materials to make selection easier.
  • Ability for materials manufacturers to submit their own materials for listing in eTool LCA.
  • Addition of new environmental impact categories (see this listed in the current release, we’re currently populating the data bases so these will become functional over time).
  • Default costs for all materials, equipment, grids and energy sources. As well as the existing detailed carbon and energy metrics, you now also get an LCA cost estimation by only entering in quantities of materials, equipment run time and operational energy.
  • Financial performance comparison chart for buildings to highlight maintenance and operational cost benefits or excesses.
  • Improved user interface for templates, and allowing “nested” templates for much faster LCA projects.
  • Share LCAs with other users.
  • More transparent and editable distance calculations for materials.
  • Annual energy cost summary.
  • Additional grids (all Australian grids now entered).
  • Expression builder for some fields e.g. you can now build a template for operational energy that takes the number of occupants and fully enclosed building area into consideration within a formula to calculate your energy demand.
  • Improved calculations and coefficients for better accuracy.
  • Ability to calculate operational water consumption.

And what’s still to come before we wind up development in September:

  • More reports!
  • Additional Environmental Impact intensities (e.g. embodied water, toxicity etc)
  • Regional LCI databases (data availability / access pending).
  • Ability to add custom distribution grids.
  • Still more templates, materials, equipment, distribution grids etc.