Why NOW carbon emissions matter more than LATER

Thoughts from the Portugal Passivhaus Conference, from John Maynard Keynes to avoided hamburgers.

In 2019 I was invited to speak at the Passivhaus conference in Aveiro, Portugal; in 2024 I was invited back to discuss what had changed in the five years since I called for Four radical steps for the Passivhaus revolution. It has been five years of plague, economic upheaval, and increasing climate chaos, but things are not all gloomy!

Here were my four radical steps from five years ago. I believe that there has been progress in many of these, some of which were not on anybody’s dance card in 2019. I am excited that they are today.

• Radical Efficiency, or adoption of tougher standards for building efficiency. There has been some progress here; Many countries have been cranking them up; some like Scotland are even considering Passivhaus with a few tweaks.

  

• Radical Decarbonization, which included both the energy supply and the shift to renewables, and also decarbonization of building materials and addressing the problems of upfront and embodied carbon. This should have been two separate steps, but embodied carbon was just appearing on radars at the time. But there has been progress on both; In Portugal, you can see the green bars representing wind, solar and hydro dominating electrical generation, growing every year. This is happening everywhere, even in Texas. We have also had the heat pump revolution, which will significantly reduce the need for heating with fossil gas.

  Upfront carbon emissions are now on almost everybody’s radar in the building industry, with reporting requirements and regulation coming soon just about everywhere. And of course, we have the boom in mass timber, straw, and other lower carbon ways of building.

  

• Radical Simplicity was a call for rethinking design, quoting Dieter Rams’ 10th principle: “Good design is as little design as possible… back to purity, back to simplicity.” Not much has happened here, and while I think it is still important, I now would consider it a subset of sufficiency- how many bumps and jogs do you really need?

  

• Radical Sufficiency, where we ask how much do we really need, and how much is enough. This is finally getting some traction; people are beginning to see that there have to be limits, that a 5,000 square foot Passivhaus is not necessarily a good thing, and in the words of engineer Will Arnold, we simply have to use less stuff. Sufficiency is in the IPCC’s 2022 mitigation report; it’s in the Declaration de Chaillot that was signed in Paris by 74 countries; the group I was involved with in Paris is presenting at COP29: “We can’t meet Paris goals without Sufficiency — avoiding demand for resources while delivering well-being for all.“

My preoccupations have all come together in the SER (Sufficiency, Efficiency, Renewables) framework developed by Yamina Saheb of the IPCC- we need all three working together. (another reason I am dropping simplicity, SER is the future)

NOW vs LATER emissions

I started this post with my slide of John Maynard Keynes, because I believe that the discussion of upfront/embodied carbon has to evolve. The accepted definition of embodied carbon has come to include emissions in the use stage and in the end of life stage, with upfront carbon being a subset of embodied carbon. The entire reason for coming up with “upfront carbon” was to simplify things, and it’s getting complicated. Our problem is NOW carbon emissions, where every gram or kilogram bring us closer to 1.5 degrees of warming. I am not worried about replacing the carpeting in ten years or deconstruction of the building- what matters is NOW.

Hence John Maynard Keynes. Perhaps I am feeling my age; I literally do not have time for whole lifecycle analyses. We don’t have a long run. My core message of Aveiro was that we have to worry about now rather than later, and we can fix this with sufficiency, efficiency, and renewables.

On the radar: Avoided Emissions

Another thing nobody talked about five years ago was “avoided emissions,” defined as “the difference in total lifecycle GHG emissions between a company’s product and some alternative product that provides an equivalent function.” Or in buildings for example, using mass timber instead of concrete.

I fear this will be a big bandwagon in the next few years- many are talking about calling them “Scope 4 emissions.”

I used to think they were a terrible idea, but I have come to like them; I can justify my flying to Portugal by not using an alternative product, a hamburger responsible for 3.3 kilograms of carbon. I promise to not eat 484 hamburgers, which given the American average of 154 hamburgers per year, will take 3.14 years, but will avoid the emissions equivalent to my flight. I don’t eat many hamburgers, but avoided emissions are imaginary anyway, so why not count them? They want me to come back to Portugal next year, so I had better promise to eat fewer imaginary pizzas too.

In the discussion after my talk, I was asked by moderator Marlene Roque if I was an optimist or a pessimist about our chances of getting through this crisis. I responded by noting that I am not a doomer; I am sitting there under my final slide, a quote from climate journalist Amy Westervelt, writing about the 2022 Mitigation Report from the IPCC: “The technologies and policies necessary to adequately address climate change exist, and the only real obstacles are politics and fossil fuel interests.”

Coincidentally, Kjell Anderson said much the same thing yesterday but I didn’t have time to add it to my slideshow, so I will add it here: “Naivety is thinking that some future tech will stop climate change. We know the problem, and have nearly all the solutions we need. We only need the will to actually solve the problem and not get distracted by the fevered dreams of techno-utopias.”

Summary and conclusion: No more distractions. No more delays. We know what to do, and when.