Redução do Impacto do Ciclo de Vida do Edifício – LEED (Portuguese)

Análise de Ciclo de Vida (ACV) é uma metodologia usada para avaliar os impactos ambientais associados a todas as etapas da vida de um produto ou serviço. É uma abordagem holística que engloba a extração dos materiais, processamento, fabricação, distribuição, uso, reparo, manutenção, descarte e reciclagem ao fim da vida útil. A ACV quantifica os impactos ambientais e compara a performance por meio da funcionalidade do produto ou serviço. A performance de um prédio comercial, por exemplo, pode ser avaliada por meio do impacto ambiental por m2 de área locável por ano (kgCO2/m2/ano). O estudo de ACV permite identificar as potenciais áreas para aumento de performance e redução de impacto ambiental, podendo também incluir recomendações de melhoria para a equipe de projeto. A ACV é regulada pelo padrão internacional ISO 14044 (e EN15978 especificamente para edificações) e a aplicação na área de construção civil é utilizada mundialmente para promover desenvolvimento sustentável.

Na certificação LEED, o objetivo do crédito Redução do Impacto do Ciclo de Vida do Edifício é otimizar o desempenho ambiental de produtos e materiais e permite obtenção de até três pontos. Apesar da metodologia permitir avaliar impactos relacionados a todo o ciclo de vida do projeto, este crédito LEED (opção 4) tem o foco apenas na estrutura e recinto do edifício, durante período de 60 anos. Ao comparar a performance do projeto proposto com o modelo de referência (Baseline), a equipe de projeto deve demonstrar redução de impacto de no mínimo 10% em pelo menos três categorias de impacto (por exemplo: aquecimento global, depleção da camada de ozônio e eutrofização).

A eTool, empresa Australiana especializada em avaliação do ciclo de vida de todo o edifício, desenvolveu o software eToolLCD que atende aos requisitos técnicos da norma ISO 14044 e pode ser utilizado na certificação LEED. A eTool iniciou operações em 2012, já completou mais de 300 análises internacionalmente e é pioneira no uso de ACV para certificação na Austrália (Green Star). Atualmente, está expandindo os serviços na Europa (BREEAM) e nas Américas. Os projetos LEED que utilizaram o software eToolLCD incluem: King Square 2 – Cundall (Austrália), Wildcat Building – Arup (Dinamarca) e ENOC Tower – AESG (Dubai).

“A única forma de garantir redução de impacto ambiental é quantificar a performance ao longo da vida útil do projeto e a metodologia de ACV foi desenvolvida para auxiliar na tomada de decisões. Este crédito LEED será muito importante para as equipes de projeto trabalharem de forma ainda mais integrada e o software eToolLCD facilita muito esta análise”, afirma Henrique Mendonça, engenheiro da eTool que está de volta ao Brasil depois de passar cinco anos na Austrália e se especializar na prática de ACV de toda a edificação.

Saiba mais sobre nossos projetos recentes aqui.

 

 

LCA – More than just easy credits

Since being awarded IMPACT compliance in Christmas 2015 eTool now have many clients successfully using eTool on either a consulting basis or as LCA software providers.  With an IMPACT compliant LCA they can guarantee the two bonus LCA Materials credits in Breeam New Construction 2011/2014. These credits are awarded as a bonus to the Green Guide materials credits and awarded for completing an LCA and reporting on the results. 6+1 credits can also be achieved under Breeam Fit-out/Refurbishment/International, up to 23 credits in HQM and 3 under LEED.  The tool can also be used to assist in life cycle costing Man 2 credits, and Mat 06 Resource Efficiency.  The Bre are trying to encourage uptake in LCA and for the time being the credits can be applied at any stage of the design – effectively points for trying.

Below are just some of the clients who we have been working on LCAs with to date.  Although the primary motivation is often Breeam related, LCA is also providing some fantastic learning outcomes for design teams.

etoolclients

“We have been using eToolLCD for the last year and have completed 3 certified assessments.  As with any new software there is a learning curve involved but the training and level of support has been excellent and we can now complete an IMPACT assessment on our project in a couple of days (depending on complexity).  This has enabled us to give our clients and design teams valuable information on the environmental impacts of design options as well as giving an additional 2% to the projects BREEAM assessment once the eToolLCD model has been certified.” David Barnes, Volker Fitzpatrick 

Find out more about our recent projects here.

 

 

Closed Loop Recycling and EN15978 – how does it work?

I’ve heard its complicated why is that?

We need to reward recycling but also have to be careful not to double count the benefits (at the start and end of life for example).  The approach under EN15978 is as follows:

  • to reward “design for deconstruction” as the key driver that determines the net results over the whole life of a building
  • to allocate economically, so if a product is a waste product at the end of the buildings’ life (there is no market for it, so it costs money to remove it from site rather than having some sort of scrap value) then any benefits associated with recycling that product are picked up by the next person who uses it.  So essentially, recycled timber is all rewarded at the start of the building’s life.  Recycled aluminium is all rewarded at the end (in net terms)

Allocation of reused products from other industries are also done economically, one example of this is recycled fly ash or blast furnace slag in concrete.  Because Blast Furnace has some value, it’s not as attractive environmentally as fly ash

The rules for recycling allocation under the EN15978 methodology were initially somewhat mind-boggling for me.  To understand them you will  likely need to take a number of re-visits and you should try to wipe out any preconceptions you may have on recycling.

So how does it work?.

Lets start with what is included in the scope of En15978 first,

boundary

Note that Module D is actually a form of “System Expansion” and one could argue is outside of the life cycle of the building.

Before we look into recycling allocation further we also need to understand a few definitions.

Recycled content is the proportion of recycled material used to create the product, the global industry average recycled content of aluminium today is approximately 35%. This means that in 100kg of aluminium 35kg comes from old recycled aluminium and 65kg comes from new raw material.

Recycling rate is the proportion of useful material that gets sent back into the economy when the product comes to the end of its life. The global industry average recycling rate of aluminium today is approximately 57%. This means that in 100kg of waste aluminium 57kg will be recycled into new aluminium products and 43kg will be sent to landfill.

Closed loop recycling, whereby a product is recycled into the same product (e.g. steel roof panel recycled into steel reinforcement).  The loop is closed because when the steel product comes to the end of its life it can be recycled into a new steel product (theoretically this can happen continually forever).  Closed loop is more straightforward to calculate as the emissions are directly offset by the new product that would have been required to be made from scratch.

Open loop recycling is when the product is used to create something new (e.g. old plastic bottles recycled into carpet).  The loop is open because the plastic now in the carpet required other material inputs to create the carpet and cannot be recycled further (if a process is developed that can continually recycle the plastic carpet then it becomes closed loop). We use economic allocation to understand the impacts that are being offset.

Now lets focus on a closed loop recycling example of a standalone 1000 kg of ‘General Aluminium’ modeled in eTool.  Under EN15978 scope impacts under module D – Benefits and loads outside the system boundary are quantified.  This includes closed loop recycling which is not directly related to the actual physical boundary or life cycle of the building.

The life cycle stages for the aluminium are shown below

alum recy 1

Kg CO2e by LC stage for 1000kg of general aluminium 

Hang on, the impacts are bigger for the 100% recycled content option???

Well, there is an initial saving in the product stage of 18,280 kg CO2e from using 100% recycled content aluminium versus using a 100% raw material. The no recovery option also gets a small advantage for transport of waste (C2) because landfill sites tend to be closer to a building than recycling sites on average. The no recovery option is also (very slightly) penalised for disposal impacts, if the aluminium is recovered it has 0 disposal impacts because it is sent to the recycling plant and these impacts are counted in the A1-A3 stage of the new aluminium product. The interesting result though is in the closed loop recycling.  We have a credit applied to the aluminium that is recovered and put back in the economy. This is effectively offsetting the assumed extraction requirement for the new aluminium to be used in the (aluminium) economy – for example in the next building.  Likewise aluminium that is not recovered causes a higher net demand for new aluminium.  To determine the ‘credit’ or ‘penalty’ at the end of the building’s life, the net increase in new aluminium required due to the use of the aluminium in the building is calculated.  In the 100% recycled content, 0% recovered the material is penalised by the equivalent mass of new aluminium which will need to be extracted to supply the next building.

Hmmmmmm…

Yes it may seem counter-intuitive but try to think of the world aluminium economy as a single life cycle entity.  If everyone used only 100% recycled aluminium that has 0 end-of-life recycling rate (ie it ends up in landfill) then we would soon run out of recycled aluminium available.  We would have to go back to using raw aluminium (maybe even start digging it back out from landfill!).  By encouraging recovery of the aluminium EN15978 is trying to discourage the overall extraction of the raw material.

O.K. That wasn’t too bad

So far so good but it gets trickier! Lets imagine we have fully recycled content and fully recovered aluminium,

Well you get the best of both worlds – reduced product stage and closed loop credits right?

Wrong!  Here is what happens….

alum recy 2

Kg CO2e by LC stage for 1000kg of general aluminium 

The minus CO2e credit at end of life can not be applied in this instance because you are already using 100% recycled aluminium. There is no material extraction in this case to offset and your end-of-life credit is 0. You don’t get penalised for the added extraction for the future building but you don’t get credit for it because that has already been given in the product stage. Under EN15978 there is actually a very similar amount of carbon associated with a 0% recycled/100% recovered aluminium scenario and a 100% recycled/100% recovered aluminium.

Whoa, that’s deep.

Its a tricky one and there is certainly an argument to say this is not encouraging the right behaviour but the emphasis on end-of-life treatment means that the impacts are accounted for and credit is given without double counting.

So what do we take from all of this?

Recycling content and rate is an important consideration in buildings but it is no silver bullet. Every little helps in sustainability though. Focus on the durability and deconstructability of the product over the recycled content which under EN15978 has a relatively small impact on the environmental performance.

*Note figures show are taken from eToolLCD September 2016

References: Recycling Rates of Metals, T E Graedel, 2011

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.

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A Rough Carbon Budget For Buildings

Why A Carbon Budget?

As we learn more about greenhouse (GHG) pollution and global warming we’re getting better at understanding cause and effect. There’s lots of complexity, obviously. However, the variables are slowly being identified, tested, and fed back into the models. Last year the media latched onto a story that global warming had ceased. I wish the stories indeed did debunk climate theory. Unfortunately not. We’re just in a period of warmer oceans and cooler atmosphere. Will Steffen explained this in a very objective manner when questioned in the Senate Committee on Extreme Weather Events (see page 12 of this transcript). Anyway, all the scientific research into climate change now enables us to make predictions of warming based on the volume of GHG we release into the atmosphere. And we’re even able to make predictions about what effects this may have. The below infographic is an incredibly good summary of these predictions, and the background data is rock solid if you’re interesting in looking into this further.

KIB_Gigatons_CO2_Apr14_A4

 

It’s pretty clear we need to try to limit warming to two degrees. The big reason for this is that there are tipping points for our climate, which trigger events that force more warming. Some examples include melting of arctic tundra and stored methane, release of methane from sea bed methane clathrates or the collapse of the amazon due to drought and fire. We don’t actually know at what point these events will happen and they may even happen before we get to two degrees warming. What we do know, is that it’s highly likely they will happen if we keep warming the planet. Even without these events occurring, we’re on track for four degrees of warming by the end of the century. Four degrees will probably put so much pressure on food resources there’ll be major global conflict. Not over land, or oil, but over food. It could get very messy.

A Per Capita Carbon Budget

So, we need to work out how much more carbon we can release to avoid these events, we need to set a budget. There is actually a level of GHG pollution that the planet can happily cope with naturally through chemical and biological sequestration. It’s a rubbery number, but sits at about 2.0 tCO2e per person. In 2050, accounting for population growth, we really need to be aiming for approximately 1.0 t CO2e per person per year which would actually enable us to reduce the GHG in the atmosphere. This, then, is our sustainable level of GHG emissions on a per capita basis. Some calculations on this here and here (with slightly different results).

Apportioning to Economic Sectors

Relating this to buildings is a little difficult because we don’t really know how the economy is going to decarbonise. There might be breakthroughs in certain sectors that enable it to effectively zero its GHG emissions, whilst others may find it very hard to shake the existing thirst for fossil fuels (or land use change). If however, we assume that all major sectors of the economy decarbonize together, then we can essentially take each sector’s current percentage of GHG emissions and multiply it by 1.0 t CO2e to yield the per capita budget for each sector. This is one of the best diagrams I have come across to explain GHG flows through the economy. It’s taken from a great publication called Navigating the Numbers.

GHG Flows

GHG Flows

In the diagram, the column “end use activity” is what we need to focus on to determine how current GHGs are apportioned across our economy. Directly, buildings are responsible for 15.3% of GHGs. However, there are a lot of indirect emissions that relate to buildings if you take a life cycle approach to measuring an impact of a building. These include transportation of materials to the site, transportation of equipment and labour, construction energy, emissions relating to materials production, further transport, and equipment use to maintain the building. Then deconstruction, demolition and landfill emissions. There may also be land use change emissions associated with some building products, or urbanisation as well. If we make the below assumptions regarding the allocation of these indirect emissions to buildings (which are not based on research, but I believe are reasonable), we land at a number of 26% of total GHG emissions relating to buildings.

  • 60% of building energy use relates to electricity to determine distribution and transmission losses
  • 70% of coal is used for electricity or downstream processes attributed to buildings
  • 30% of oil and gas gets used for electricity or downstream processes that can be attributed to buildings
  • Unallocated fuel combustion is proportionally attributed to all end uses
  • 1% of air transport and 10% of all other transport relates to building construction, maintenance, design or management.
  • 50% of iron, steel and cement is used in building construction or maintenance
  • 10% of chemicals are used in building construction or maintenance
  • 25% of aluminium and non ferrous metals are used in building construction or maintenance
  • 10% of other industries are providing materials or services to building construction or maintenance
  • 25% of land use change emissions due to harvest and management of forests relate to construction and maintenance of buildings
  • 15% of all landfill gas emissions relate to disposal of construction waste
  • 75% of waste water treatment emissions relate to building waste water

Building Related Emissions

These assumptions and calculations at this point are moving pretty quickly towards “back of the envelope”. The only way I can really justify this is that there are no numbers out there telling us what is a sustainable level of GHG emissions for buildings. So don’t hang your hat on these numbers, however, in lieu of more robust calculations, here’s a starting point.

A Carbon Budget For Buildings

We can now set a rough carbon footprint for environmentally sustainable buildings at 260kgCO2e per year per capita. This will be split between residential dwellings and other buildings. If we assume the split is the same as the direct GHG split in the “Navigating the Numbers” flow chart, that gives us a budget of 168kgCO2e per year per capita for residences, with the remainder of building related GHG distributed to workplaces, hospitals, civic buildings etc. We haven’t done any work on how to distribute the remainder amongst these other buildings as it gets pretty complex but watch this space. For residential buildings in Australia, we have a lot of work to do to achieve this budget. See the below chart for a visual on that.

Australian Residential Buildings

Close

Although these numbers require more work to confirm, they provide some guidance in lieu of other sources. They display the extent of the challenge. In particular, note in the last chart that the target is many times less than even the embodied GHG of current “average” buildings in Australia. I extend on this topic in this post, exploring some lateral thinking to solving the challenge of hitting our carbon budget for buildings. Note, this is an update on the video attached to the next post so you may spot a difference in the figures.

 

 

Vote for eTool in GE’s Ecomagination Challenge

GE’s Ecomagination are looking for breakthrough ideas, technologies and innovations to help lower ANZ’s carbon footprint. They launched a competition back in August to search for the brightest ideas and there are only a few days left with the deadline closing in fast this Friday.

We’ve added our LCA software into the mix and would love your support!

All you have to do it head over the website here, log in via Facebook, Twitter or LinkedIn (only takes a second) and then hit the ‘I support this idea’ button. If you’re feeling inspired, leave a comment about our LCA and how you think it can help lower ANZ’s carbon impact!

Energy efficient fridges – a waste of money or saving the planet?

Although energy efficiency appliances have improved dramatically over the past decade, we’re always a little cautious about recommending highly rated energy efficient fridges to our clients, as the main focus is on temperature performance to keep food fresh for longer periods, which can become problematic when looked at a little more closely.

Let’s explain what we mean exactly…some fridges save on energy by having longer “compressor-off cycles”, which causes the temperature inside to fluctuate. Ice-cream is a good indicator of temperature fluctuation, as it can partially melt during the off cycle and then form gritty crystals when it refreezes – we’ve all been there! Poor uniformity may mean that there is a 3°C average in the fresh food compartment, but more than 5°C in other parts, such as the door shelf. This can result in milk going off much faster than you would expect or are happy about.

In terms of environmental impact, the embodied energy of the food is likely to be at least 10 times more than the energy consumed by the fridge, so sometimes a fridge which is actually less efficient and uses a bit more power can extend the life of food quite considerably, making it the more sustainable option! So what can you do to make a lower rated fridge even more sustainable?

Well, properly ventilated fridges can represent large savings in energy efficient houses and when considered as part of the kitchen design, it’s very simple to achieve. Clever options include sealing the fridge into the cabinets and making use of the cool air and exhaust ducting; the closed space keeps cold air inside and around the fridge, away from the kitchen. The air that becomes hot as it passes through the refrigeration mechanism is drawn either up to the ceiling and exhausted outside the house or over the top of the refrigerator and can be ventilated into an upstairs room such as bathroom or laundry to dry the towels.
The ability to increase the efficiency of a fridge with well designed cabinetry and ventilation is not related to the fridge specification, however, so is something we can comfortably model in our LCAs.

In addition to being wary of the energy rating and trying to implement the refrigeration air flow in your home,  we would always suggest buying the right sized appliance to suit your needs. A large model with the same star rating as a smaller model uses more energy and generates more Greenhouse Gas, and if you think about it, do you really need a gigantic fridge?
A cool cupboard will keep most of your fruits and vegetables in good nick in most climates, allowing you to choose a smaller fridge. Cool cupboards should be located in the coolest part of the house (usually your kitchen or pantry) and have good airflow in at floor level and out through the ceiling.

We know it’s become a bit of a habit in Australia, but try and think of a way to do without a second fridge to save on both the cost of buying and running it and the environmental impact of its use, manufacture and disposal.

Ongoing running costs can easily exceed the original purchase price of an appliance, so always add the purchase cost and the lifetime running cost together to get a more accurate picture of the total cost of an appliance. For example, a fridge that consumes 1kWh extra per day represents over $800 extra operating costs in a decade, without even considering potential energy price increases.

One last tip – especially if you have kids at home – hang a sign on the fridge door that says ‘Only open when necessary!’ Opening fridge doors only when you need to get something out or put something back in, as opposed to leaving it open whilst your make a sandwich, will save between 5-10% in running costs.

References:

http://sustainablehouse.com.au/ Michael Mobbs’ Book

http://www.choice.com.au/reviews-and-tests/household/kitchen/fridges-and-freezers/fridges-review-and-compare.aspx

http://www.yourhome.gov.au/technical/fs64.html