What Are "Locked-In Emissions" and Why Do They Matter?

Also called "carbon lock-in," it's about time.

That's my fancy efficient Laars gas boiler that I installed in my house five years ago during my "green" renovation. It is way better than the one it replaced, and I justified it because I was breaking the house into two apartments so the per-capita emissions were going way down.

But this furnace wasn't cheap, and has a life span of about 20 years, so I have now "locked in" its CO2 emissions for that time. After mentioning locked-in emissions in a recent post, I thought I would look at its history. The proper term is apparently "carbon lock-in" and was first used in 1999 by Gregory C. Unruh in his doctoral thesis, writing, "This condition, termed carbon lock-in, creates persistent market and policy failures that can inhibit the diffusion of carbon-saving technologies despite their apparent environmental and economic advantages."

More recently, Peter Erickson, Michael Lazarus and Kevin Tempest wrote a paper, Assessing carbon lock-in, where they note:

Carbon lock-in is an example of the phenomenon of path dependence—'the tendency for past decisions and events to self-reinforce, thereby diminishing and possibly excluding the prospects for alternatives to emerge...Specifically, carbon lock-in refers to the dynamic whereby prior decisions relating to GHG-emitting technologies, infrastructure, practices, and their supporting networks constrain future paths, making it more challenging, even impossible, to subsequently pursue more optimal paths toward low-carbon objectives.

They raise the question that policymakers should ask, but also that every person who buys a house or a car or a furnace should ask:

Shall they further invest in fossil-fuel producing and consuming technologies now, hoping these investments can be 'unlocked' later, if and when low-carbon alternatives are cheaper or political conditions more favorable? Or, shall they increase investment in low-carbon technologies now, even if near-term economic costs and political barriers appear high?

Peter Erickson, Michael Lazarus and Kevin Tempest /CC BY-NC 3.0

So, as this graph notes, I bought a gas furnace because the cost of gas was so much less than electricity or insulating the entire big old house, and will probably be stuck with it for 20 years. People who buy gasoline powered cars are locking in their emissions for about 15 years, and building a cement plant locks them in for forty years. The cars in particular are important because there are so many of them: "Continued investment in conventional ICE vehicles risks further entrenching these technologies at the expense of fostering alternatives, such as electric vehicles, and the systems that support them, such as recharging infrastructure."

Another study led by Chris Smith of the University of Leeds determined that if we started right now at replacing existing infrastructure at the end of its useful life with zero-carbon alternatives, "we could limit peak temperature rise to 1.5°C – as long as we start now." They are talking about everything:

Alongside power stations, cars, ships and planes, we also applied the “asset lifetime” assumption to meat cattle. Cows produce a lot of methane, so if we ate them all over the next three years without breeding any more, we could certainly reduce our greenhouse gas emissions considerably while having a gluttonous time doing so.

Carbon lock-in is adding a time component to operating emissions, a recognition that if we build something that puts out CO2 we are essentially stuck with it.

• That's one reason I have become such a fan of Passive House for building. They actually lock in carbon savings, and will never need much energy to run or emit much CO2.
• That's why we need to ban gas hookups to houses right now; builders will be forced to design homes that can run cost-effectively on electricity.
• That's why we have to stop building sprawl, where we are locking in the need for cars to get anywhere.
• That's why we need a massive investment in safe bike infrastructure, to get more people thinking that they can replace that ICE powered car with a bike or e-bike.
• That's why people like me should think twice about buying fancy efficient gas furnaces; I was just fooling myself.

I like the term "locked-in emissions" better than "carbon lock-in", thinking it more self-explanatory, but then I have been pushing "up-front carbon emissions" instead of the more accepted "embodied carbon." They are both emphasizing the emissions. Whatever they are called, we have to think about both together to really deal with this problem. And we have to start doing this right now, before we are locked-in to a disaster.