What matters is what is being emitted now, and it has to be measured to be managed.
We talk a lot about embodied carbon or embodied energy, which I have defined as "the carbon emitted in the making of building products." I have also written that "embodied energy is a difficult concept but we have to start wrestling with it every day."
It is a difficult concept because everyone has been relating it to life cycle analyses, trying to determine if, say, adding insulation saves more carbon over the life of a building than is created by making the insulation. But it is not necessarily so complicated; Geoff Milne wrote for an Australian guide to sustainability back in 2013:
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.
A few months ago I began to question the way we discuss embodied carbon, writing Forget about Life-Cycle Analyses, we don't have time.
We don't have a life-cycle to analyze, we don't have a long term. The IPCC laid it out when they said we have 12 years to limit climate change catastrophe. That means we have the here and now to stop putting CO2 into the atmosphere...That is our life-cycle, and in that length of time the embodied carbon in our materials becomes very important indeed.
Then this weekend I was in a long Twitter exchange, discussing the carbon "burp" of making stuff, when Elrond Burrell picked up the theme:
All important, but the emissions burp/vomit/spike for product manufacture & construction literally happens when a building is built, not over the lifetime. It's not "embodied" it's *already* emitted. So it's critical in terms of keeping CO2 out of the atmosphere this decade.— Elrond Burrell (@ElrondBurrell) March 31, 2019
And it hit me: Embodied carbon is not a difficult concept at all, it is just a misleading term, because as Elrond notes, it isn't embodied. It is in the atmosphere now.
Agree, and I also wonder how much people dismissing embodied carbon is the way we talk about it. Instead of embodied carbon, perhaps we should consider renaming it as upfront emissions. https://t.co/h5oql4bqHy— Jorge Chapa (@jochapa) March 31, 2019
Jorge Chapa of the Green Building Council Australia nailed it, I think, with his suggestion of Upfront Emissions. Because that is exactly what we should be measuring. Through the course of writing this, I have concluded that it should be Upfront Carbon Emissions, or UCE.
Sure but other emissions such as op’ energy, repair occur over life. To compare options could look at net present value of emissions and discount future emissions. If op energy not low enough now, need another retrofit burp later— Nick Grant (@ecominimalnick) March 31, 2019
Nick Grant is correct to note that we shouldn't lose sight of operating emissions, that 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."
Couldn’t agree more. Worrying about the impact from facade replacement in 50 years’ time is not going to save us.— Edward Vaughan Dixon (@canonburyking) March 31, 2019
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. I can think of many examples of how this changes how one thinks about buildings, and will have more on this in a subsequent post.