All emissions commitments are for zero, but is “zero” the same for all?
As part of our ongoing research programme, we have spoken to dozens of operators globally about their plans for net zero emissions. Most of those we have spoken to have made commitments to reduce to zero their direct (scope 1) and electric energy (scope 2) greenhouse gas emissions by a certain date. Some claim to have achieved this already. Most acknowledge that their indirect embedded emissions (scope 3) are their largest emissions, most difficult to tackle and will take longest time to reduce. We will discuss scope 3 in our forthcoming report.
For various reasons, operators tend to focus (initially at least) on emissions from the electricity that powers their networks (scope 2). Commendably, they look at introducing energy optimisation measures and not rely only on using ‘greener’ electricity. Partly, this is because electricity is something that they already measure, or should be measuring. Partly, there is also a strong cost saving incentive in reducing energy, so they can more readily justify this as meeting simple business logic. And partly, it just appeals to an engineering mindset as an addressable engineering problem.
The “zero-emission” claim
While these measures may secure cost benefits, they may not be progressing emissions objectives as intended. It turns out that the way operators (and any other electricity consumers) ensure that the energy they buy is zero-emission varies considerably. Indeed, there is a hierarchy of mechanisms for claiming use of zero emissions electricity with a list of new acronyms to accompany these (much to the delight of those in an industry already awash with acronyms) each with an arguably greener claim to zero emissions (see the table below for our take on the hierarchy).
Main mechanisms to claim zero emissions generated power for networks and operations (not exhaustive)
At the heart of this hierarchy is to what extent these different mechanisms are genuinely additive and generating new non-emissions electricity and to what extent are they simply displacing the bad stuff onto others. At their worst, they may be undermining genuine projects.
Is 100% zero emissions achievable?
Even where the most genuinely additive mechanisms have been adopted, there is doubt as to whether they can claim to be 100% zero emissions. With the possible exception of a handful of countries with abundant hydro, geothermal (or arguably nuclear) power, renewables energy is either from biomass (burning non-fossil fuels, which creates CO2 emissions albeit more recently extracted from the atmosphere) or from non-emissions but fickle renewable sources: solar and wind power.
The simple truth is that networks need a continuous power supply to work. Even where operators have purchased 100% renewables energy, their 100% renewables suppliers have usually had to ‘borrow’ some electricity from another (typically fossil fuel based) source when the sun isn’t shining, and the wind isn’t blowing. This energy ‘loan’ is then given back later so that the result is 100% net renewable. An elegant accounting trick that does not actually reflect the reality of what happens.
And this problem doesn’t go away if we increase renewables generation capacity because windless, dark days still mean energy has to come from somewhere else. Storage (in batteries or as hydrogen or by pumping water back up into dams) can potentially alleviate this and get away from accounting trickery to more genuinely 100% renewable sources, but this is hypothetical.
Even if and when storage is possible, there will be some embedded carbon required to build and install the generating and storage facilities (in the worst cases hydro-electric dams can have many years of carbon payback embedded in civil works, concrete and lost carbon capture of submerged ecosystems).
All this to say that operators are right to keep emphasising optimisation and energy efficiency and reducing the power they use to run their networks. However, those operators furthest on their net zero emissions journey are now also tackling the scope 3 elephant in the room that is the embedded carbon from their supply chain. With the risk of mixing metaphors, this is altogether a far tougher nut to crack.