Nobody cared much about this a few years ago. They do now.
In October, 2018 the UN Intergovernmental Panel on Climate Change (IPCC) released a report which concluded that we have until 2030 to cut our carbon emissions enough to prevent global heating to a maximum of 1.5°C.
For many, the report changed the thinking about what has been called "embodied energy", which was described a few years ago:
“It’s a line in the sand and what it says to our species is that this is the moment and we must act now,” said Debra Roberts, a co-chair of the working group on impacts. “This is the largest clarion bell from the science community and I hope it mobilises people and dents the mood of complacency.”
Embodied energy is the energy consumed by all of the processes associated with the production of a building, from the mining and processing of natural resources to manufacturing, transport and product delivery. Embodied energy does not include the operation and disposal of the building material, which would be considered in a life cycle approach. Embodied energy is the ‘upstream’ or ‘front-end’ component of the life cycle impact of a home.
We have been talking about it on TreeHugger since at least 2007, and went through at least a decade of readers calling me an idiot for going on about plastic foams. Even people who acknowledged the issue of embodied energy didn't think it was the most important issue; John Straube, an expert on these things, wrote in 2010:
Issues of recycled content, low embodied energy, and natural ventilation are not unimportant. However, if these concerns distract so much that a low-energy building does not result, then the environment is risked. ...The operational energy use of buildings is their biggest environmental impact. Green buildings, which must be low-energy buildings, need to be designed to respond to this reality.
How big is the CO₂ bucket for 1.5°C?— Glen Peters (@Peters_Glen) December 13, 2019
Well, the bucket is about to overflow in a few short years, unless we:
1. Turn off the tap (urgently)
2. Put a hole in the bottom to remove CO₂ (negative emissions)#COP25 #CarbonBudget @FutureEarth @gcarbonproject https://t.co/ycYcuFSPdF pic.twitter.com/o7JwZt7GlX
But in 2018, with the IPCC report, that reality changed. Scientists have told us that we have a carbon budget of about 420 gigatonnes of CO2, the maximum that can be added to the atmosphere if we are going to have any kind of chance of keeping warming below 1.5 degrees. Suddenly, the way we thought about embodied energy had to change.
In all of this, we should never forget that the world goes on after 2030 and we have to reach net zero emissions by 2050. Operating emissions matter as much as ever. But we have been ignoring or downplaying the upfront emissions and we really cannot.
Forget about Life-Cycle Analyses, we don't have time.
Most discussion around embodied energy involved a life-cycle analysis that would determine whether using a material like foam insulation saved more energy over the life of the building than the embodied energy of making the stuff. In most cases, over the fifty years, the foam insulation looks pretty good, as does concrete because of its inherent durability. But as Will Hurst noted in the Architects Journal,
Until now, many have also argued that concrete is a sustainable material because of its relative longevity and high thermal mass. When assessed purely in ‘whole life’ terms, they have a point. But if you accept the scientific consensus that we have little more than a decade in which to keep global warming to a maximum of 1.5°C, then embodied energy becomes the most pressing requirement for a construction industry responsible for 35-40 per cent of all carbon emissions in the UK.
Readers don't get this, and complained that "it's always a good idea to reduce CO2 emissions where possible, but making choices between materials needs a life-cycle analysis to be sure the reductions are real." I responded that we don't have time for life-cycle analyses. We don't have a long term to deal with this. "We have to concentrate our minds on reducing our carbon dioxide output by half in the next dozen years. That is our life-cycle, and in that length of time the embodied carbon in our materials becomes very important indeed."
More in TreeHugger.
Let's rename "Embodied Carbon" to "Upfront Carbon Emissions".
One of the problems I had in discussing embodied energy or embodied carbon is that the name is so counter-intuitive. Because, it's not embodied at all; it's out there in the atmosphere right now. We can't lose sight of operating emissions, we do have to invest now in preventing them over the long run, but as John Maynard Keynes noted, "In the long run we are all dead." I concluded:
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Upfront Carbon Emissions is a very simple concept. It means that you should measure the carbon generated by producing materials, moving materials, installing materials, everything up to the delivery of the project, and then make your selections on the basis of what gets you where you want to go with the least Upfront Carbon Emissions.
What happens when you plan or design with Upfront Carbon Emissions in mind?
This is my choice for my most important post of the year, when I started thinking about how this is much bigger an issue than just buildings. What happens when you start taking it seriously? I will summarize it here. To start with, Maybe you don't build things that we don't actually need, like that silly Tulip proposed by Architects Declare member Norman Foster. Fortunately it got cancelled.
You don't bury things in concrete tubes when you can run them on the surface. In Toronto where I live, they are spending billions on a new subway and on burying a light rail line because the late Rob Ford and his brother Doug don't like taking away space from cars. Millions of tons of concrete, years late, because of stupid obsessions. The same goes for Elon Musk and his silly tunnels.
You stop demolishing and replacing perfectly good buildings. The worst example of this is JP Morgan Chase in New York City, which is taking down a quarter of a million square feet of tower to rebuild it twice as big.
You would replace concrete and steel with materials with far lower Upfront Carbon Emissions wherever possible. That's why I like wood.
You would just stop using plastics and petrochemicals in buildings. That's why I don't like foam.
You would stop building so many cars, whether ICE, electric or hydrogen, and promote alternatives with lower UCE. That's why I think promoting electric cars is a problem, each has its own big burp of upfront carbon emissions, and the bigger the car, the bigger the UCE. This is why we have to design our cities to allow people to bike and e-bike safely and comfortably. "Seriously, we have to look at what the most efficient ways to get around are, in terms of both an operating and an upfront carbon footprint, and cars ain't it, even if they are electric."
World Green Building Council calls for radical reduction in Upfront Carbon Emissions.
Carbon emissions are released not only during operational life but also during the manufacturing, transportation, construction and end of life phases of all built assets – buildings and infrastructure. These emissions, commonly referred to as embodied carbon, have largely been overlooked historically but contribute around 11% of all global carbon emissions. Carbon emissions released before the building or infrastructure begins to be used, sometimes called upfront carbon, will be responsible for half of the entire carbon footprint of new construction between now and 2050, threatening to consume a large part of our remaining carbon budget.
The WGBC document is actually a must-read for the path it lays out for sustainable building. My review: "They have also set tough but realistic deadlines. They have not been dogmatic. What they propose is achievable. And most critically, they are stressing the significance of Upfront Carbon in a way that I have not seen before. This is ground-breaking and important stuff."
Architectural critic: Embodied energy matters
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It’s as if architects believe that embodied energy, which is, of course, invisible, can be wished away (or at least offset with minimal effort). This idea is reinforced by designers who declare their buildings green while either ignoring embodied energy or claiming that operational efficiencies somehow make it irrelevant—a kind of fairy tale some of us are all too happy to believe. I’m equally disheartened that architecture critics have, for the most part, failed to expose this myth in their reporting.
Embodied Carbon called "The Blindspot of the Buildings Industry"
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Of course, it’s undeniable that reducing carbon emissions from operational energy use is extremely important and should be a key priority. But our industry’s single-minded focus on operational energy efficiency raises the question: What about the greenhouse gases emitted during the construction of all these new buildings? If we really are adding another New York City to the mix every month, why aren’t we thinking about the environmental impacts associated with the materials used to construct those buildings? Well, actually, we are— or at least, we’re starting to.
Landmark study shows how to change the building sector from a major carbon emitter to a major carbon sink.More in TreeHugger and more on Chris Magwood in What is "the conventional wisdom about environmentally friendly construction"?
RIBA guide outlines radical plan for a sustainable future.
Finally, the Royal Institute of British Architects produced a really significant proposal for how we should be building everything now, with very strong language:
The time for greenwash and vague targets is over: with the declared climate emergency, it is the duty of all architects and the construction industry to act now and lead the transition to a sustainable future that delivers the UN Sustainable Goals.
I stress again why this is so important right now:
Buildings take years to design and years to construct, and of course have a lifespan that goes on for years after that. Every single kilogram of CO2 that is emitted in the making of the materials for that building (the upfront carbon emissions) goes against that carbon budget, as do operating emissions and every litre of fossil fuel used to drive to that building. Forget 1.5° and 2030; we have a simple ledger, a budget. Every architect understands that. What matters is every kilogram of carbon in every building starting right now.
The RIBA challenge covers all aspects of building, but devotes a lot of attention to upfront carbon emissions. Everyone in architecture and design should read it. (TreeHugger summary here)
The absolutely key point of these documents is that 2030 is the imperative that we have to act not in 2030 but immediately. We have a bucket of carbon that is almost topped out and we have to stop adding to it. As Gary Clark, chair of the Sustainable Futures Group of RIBA concludes:
This is our last chance to avert a climate disaster. We must act now.