Time for the Carbon Half-Life?

Net zero is too fudge-able, we need to drive action now.

In 2012 Futerra worked with Kingfisher – owners of B&Q, Castorama and others – to build their sustainability strategy around the concept of net positive. At the time, the idea to do more good than harm across your major, material impacts, was world leading. Central to this landmark strategy was a fundamental mindset shift; a shift from picking targets and goals that took their starting point from what was considered practical and manageable (and frankly, not too inconvenient), to an approach where targets would be set based on what was necessary to be truly sustainable. With CEOs and Heads of State recognising that it is the natural world that gets to determine how much carbon is too much, the mindset shift, from, “what do we want to do?” to, “what needs to be done?” has been central to the recent and rapid spread of commitments to contribute net zero carbon to the atmosphere.

Since 2012, and especially in the last few years, net zero carbon commitments have gone mainstream with over two thousand of the worlds’ major businesses and 2/3 of global GDP now covered by a net zero target. However, what should be cause for great celebration is starting to feel like a potentially hollow victory. While the net zero concept could be applied to many resources or emissions, net zero carbon goals have come under scrutiny and scepticism, especially since several oil majors have recently joined in the fun with their own commitments.

While a few idealists call for ‘real zero’ targets (where businesses release no greenhouse gases at all), the most common critique of net zero is not aimed at the goal itself but at the strategies put forward by companies to deliver on it. While net zero is a goal that must come with a deadline, it is agnostic as to how you get there.  This has meant that many of the heaviest polluters that have committed to be net zero by 2050, plan to continue to expand their emissions today while promising dramatic cuts in a decade or two once promising new technologies (hopefully) reach attractive scale and cost thresholds. In short, net zero, critics argue, provides cover for greenwashers to keep pumping out emissions when we most need to cut them.

And yet, I believe that the remarkable uptake of net zero commitments is a sign of great progress. A core concept of sustainable business has gone from being leading edge to being considered a table stake for any major organisation wishing to manage its ESG risks. What is more, a cross-sector consolidation around an approach to managing carbon with a common language and framework, is an incredibly valuable foundation for concerted, co-ordinated action on climate change.

While it would be a waste to throw away the progress made on net zero, not addressing its flaws risks a wave of scepticism towards sustainable business in general. To meet this challenge, I believe we need a new concept, one that overcomes the loopholes and get-outs of a net zero commitment, by focusing strategies on near-term emissions reductions. One that will drive action on the most urgent and immediate first step of the climate challenge – peaking emissions and bringing them down.

With that in mind, I propose a new term that should be coupled with every net zero strategy:


The Carbon Half-Life – The date at which a business will emit half as much carbon as it did at its peak.


I believe this will give a much clearer picture of the pathway a business is on and enable us all to spot those who are using net zero as a cover for delaying action. The two commitments can be easily combined: e.g. we have a goal to be net zero by 2040 with a Carbon Half-Life of 2032. There is also, the enormous advantage of bringing the focus for action much closer to the present moment. It’s easy to commit to change in 20 or 30 years’ time, but if you need to halve your emissions in ten years, then you probably need to peak them in the next 2-3, which is the sort of time frame modern business can just about deal with.

To make the Carbon Half-Life commitment as meaningful as possible, I believe there are 3 necessary components:


Inset, not offset

We need a commitment that will complement net zero and compensate for its key weakness. By excluding any carbon reduction or sequestration outside of the value chain, we can start to get a clear picture of a business’s direct contribution and trajectory. While a Carbon Half-Life should be entirely exclusive of offsetting, it should allow for in-setting: carbon capture and storage/utilisation, directly related to the business’s operations.


Absolute, not relative

While it is possible that, like with other carbon metrics, a carbon half-life could be a relative/productivity metric (carbon per unit sold / carbon per $ value created), the purpose of proposing it is to ensure that we are making real-world progress towards a stable climate. Therefore, it should only and always be an absolute carbon metric (total carbon emitted, regardless of the organisation’s economic growth).


Peak, Not Baseline

Many carbon targets today, both business and national, are rendered very difficult to compare and comprehend due to the free-for-all on baseline years (the year against which the reduction is measured). For example, which of the following targets is better: The UK’s commitment to cut 68% by 2030 on a 1990 baseline, or the US commitment to cut 52% by 2030 on a 2005 baseline? To overcome this, the Carbon Half-Life should be orientated to the business’s peak emissions, not a reduction from its self-chosen baseline. As well as making commitments more comparable, this will have the added benefit of driving a nearer-term focus on a peak emission date, overcoming some of the can-kicking behaviour of those trying to fudge net zero.



I’m not claiming to have thought this through to all it’s possible ends and potential uses and abuses. Instead, I am simply offering it out to the community for discussion, refinement, and testing. Perhaps, once a business has reached its Carbon Half-Life, it can then declare it’s Carbon Quarter-Life, the point at which it will have halved again its remaining emissions? Perhaps the half-life is not even a self-created goal – it could instead be an independently assessed trajectory based on the action taken by the business so far and the future spending it is committed to? Businesses could have their Carbon Half-Life audited as part of their sustainability reports, or even certified. On one hand, this might raise credibility, on the other, it could slow uptake. Perhaps it’s best to get the ball rolling and then increase the sophistication once buy-in starts to gather pace? I am, as always, open to suggestions.

Back to Top