Feasibility of decarbonising electricity in G7 by 2035
G7 countries commit to decarbonise electricity by 2035
At the annual G7 summit in 2022, G7 countries and the European Union committed to achieve “fully or predominantly decarbonised” electricity by 2035 (hereafter “G7” includes EU). This political pledge presumably follows the International Energy Agency’s recommendation for G7 to decarbonise electricity by 2035 and the rest of the energy sector by 2050 in order to keep the 1.5 °C global goal within reach. In other words, decarbonising electricity by 2035 is a critical stepping stone not only for G7 but also for the rest of the world to mitigate the risk of climate change.
Is this target feasible?
Ambitious political commitment is only meaningful if it is actually implemented. But how feasible is it for G7 to achieve this target and what would it exactly require?
In order to answer these questions, we looked at the evolution of electricity sectors in G7 in 1960-2020. We traced the type, direction, and speed of transitions over time and particularly compared the transitions before and after 1990 when the global climate regime first emerged, gradually strengthening since.
Figure 1 shows that the electricity transitions in G7 in 1960-2020 can be broken into two major periods:
Figure 1: Evolution of electricity sectors in G7 in 1960-2020 (Methods note at the end)
(1) 1960-2005: highly fossil dependent ‘energy additions’ when different electricity sources were built ‘on top’ of rather than replacing each other; within this long period:
the growth of fossil-based electricity has slowed from over 3% of the total electricity supply in 1960-75 to 1-2 % or less in 1975-2005;
there was a short period around the early 1980s when the expansion of nuclear power brought the growth of fossils to a halt; subsequently, nuclear power stagnated and the growth of fossils resumed.
(2) 2005-2020: low-carbon transitions with modern renewables replacing fossils under stagnating electricity demand.
Interestingly, the recent growth of modern renewables in 2015-2020 at 1% of the total electricity supply per year is still lower than the expansion of nuclear power in 1970-1985, which was generally over 1.5% while achieving the historical max speed at 2% in 1980-1985. In other words, the increasing concerns over climate change post-1990 have not accelerated the growth of low-carbon electricity as compared to its historical maximum.
Figure 1 also shows that the recent decline of fossil fuel use in electricity in G7 is due to the stagnation of electricity demand rather than to a fast growth of modern renewables (grey shaded area).
In contrast, the transition envisioned to achieve decarbonised electricity by 2035 is strikingly different: it envisions a growing electricity demand enabled by the growth of low-carbon electricity at 4.5% per year (4.5 times faster compared to 2015-2020) and the decline of fossil-based electricity at 2.6% per year (2 times faster compared to 2015-2020) in 2020-2035.
Such rapid energy transitions have been extremely rare: comparable rates over 5-year periods were only observed in about 10% of historical low-carbon transitions in developed countries at the individual country level (see the bottom half of Figure 1 and the Methods note at the end of this blog). In the future, not only this speed needs to be achieved by all G7 countries at the same time, but it must be sustained for 15 years between 2020 and 2035.
Are G7 on track?
Decarbonising electricity in G7 by 2035 is an extremely challenging target and there is no time to waste as any delay would require even higher speed of transitions in the future. Are G7 now on track to the target?
Unfortunately, not at all.
Figure 2 shows that last year in 2021, most G7 countries actually moved in the opposite direction from the target, by increasing the use of fossils and slowing down the growth of low-carbon electricity. The only exceptions are EU member states (shown as “EU” in the figure, excluding France, Germany, and Italy which are analysed separately) and Japan who expanded low-carbon electricity at 3.5% and 4.1%, respectively. It is also notable that only Japan reduced the use of fossils in 2021, though at a lower rate than in 2015-2020.
Figure 2: Latest developments of G7 countries in 2021 *France and Canada are excluded as their electricity systems are almost decarbonised already.
Prominently, in Germany and the UK, which are often considered as leading countries in low-carbon transitions, low-carbon electricity not only stagnated but declined from -2% to -4%. While this is partly due to non-favourable weather conditions, it is worrisome as achieving the challenging 2035 target does not have room for such yearly fluctuations: the high transition speed must be constantly maintained or compensated with even higher speed in the following years.
Conclusion
Achieving decarbonised electricity in G7 by 2035 requires overcoming three unprecedented challenges: (1) low-carbon electricity needs to grow 4.5 times faster at 4.5% per year than the most recent rate at 1% in 2015-2020 (equivalent to doubling the speed of nuclear power development in 1980-1985), (2) fossil electricity needs to decline 2 times faster at 2.6% per year than the most recent rate of 1.3% in 2015-2020, and (3) these rates need to take place immediately (we are already in delay), across all G7 countries, and continuously towards 2035. This means replicating the top 10% low-carbon transition speed historically observed over 5-year periods in developed countries, and sustaining such speed instead for 15 years.
Looking at the historical evolution and the latest development of energy transitions in G7 countries, achieving their decarbonised electricity target by 2035 is extremely challenging. As our previous analysis on the feasibility of Germany’s new renewable targets argued, overcoming this challenge would require ground-breaking changes rather than incremental accelerations of transitions. Examining the underlying conditions for what made it possible for G7 countries to achieve the historical max growth rate of low-carbon electricity with nuclear power in 1980-1985 may provide suggestions, though this historical rate still fall short of the speed necessary in the next decade. Whether replicating and reinforcing such conditions is feasible today is an open-end question but it may be this level of change that must take place to decarbonise electricity in G7 by 2035.
This blog entry summarises the research poster presented at Scenarios Forum 2022. Please cite as:
Suzuki, M., Jewell, J., and Cherp, A., 2022. Evolutions of electricity transitions in 1960-2020: Gap for achieving net-zero in G7 by 2035. [Poster]. Scenarios Forum 2022, 20-22 June, Vienna.
Methods note, Figure 1:
Each pie represents 5-year changes in supplying electricity (i.e. 65-70 at the top refers to the transitions in 1965-1970. The size of pies represents the log-transformed size of the electricity system. Four transition types are based on the interaction between the changes in low-carbon and fossil-based electricity (ie. “energy additions” where both sources grow at the same time, “low-carbon transitions” where low-carbon electricity grows but fossil-based electricity declines). Speed zones for low-carbon transitions are delineated so that ”Regular” zone subsumes 70% of low-carbon transition episodes over 5 years in developed countries (G7 and all European member states, Switzerland, Norway, Lichtenstein, Australia and New Zealand), “Rare” zone the next 20%, “Extremely rare” zone top 10%.
