Renewable Energy Institute’s Comment on the Government’s NDC Proposal Proposed "60% Reduction Target by 2035" Only Represents 49%A Shortfall and Missed Opportunity for a Developed Nation

in Japanese

At a joint meeting of the Ministry of Economy, Trade and Industry (METI) and the Ministry of the Environment (MOE) held on November 25, the two ministries announced a draft proposal for the upcoming Nationally Determined Contribution (NDC) set to be submitted to the United Nations in February next year. The draft proposes reductions of 60% by 2035 and 73% by 2040, described as part of a "linear pathway to net-zero by 2050." 

Domestically, some earlier discussions suggested allowing greater emissions (overshooting) in 2035 and 2040, with more significant reductions or atmospheric carbon removal occurring later. In this context, some may have positively received the decision to propose a linear pathway.

However, while the government’s draft appears to align with the IPCC’s suggested 60% reduction by 2035, it only achieves an actual reduction of about 49% from the 2019 baseline used by the IPCC. This level of ambition falls short of fulfilling Japan’s responsibilities as a developed nation.

The 60% reduction target only amounts to 49%

In March last year, the IPCC released its Sixth Assessment Report, highlighting the urgency of the climate crisis with the statement: "Climate change is a threat to human well-being and the health of the planet. The window of opportunity to secure a livable and sustainable future for all is rapidly closing." Alongside this warning, the report outlined global greenhouse gas (GHG) reduction pathways required to limit warming to within 1.5°C with a probability of less than 50%, either without overshoot or with minimal overshoot. The target for global GHG emissions under these pathways is a 60% reduction by 2035 compared to 2019 levels (Table 1).

Table 1: Reduction rates of GHG and CO₂ raised by IPCC 

In response, the government proposal presented this time is based on the year 2013. When compared to the IPCC's reference year of 2019, the reduction rate until 2035 would be a 53% decrease. The reason the reduction rate being relatively small is that 2013, which Japan uses as its reference year, was the year when the Fukushima Daiichi nuclear disaster led to a zero reliance on nuclear power, increasing dependence on thermal power generation and causing a sharp rise in emissions¹.

Furthermore, another issue is that Japan's NDC adopts an uncommon method to calculate emission reduction. It uses gross emissions for the reference year and net emissions (gross emissions minus absorption from forests and other sources) for the target year, known as the gross-net method². While there was indeed absorption in the reference year of 2013, these are not counted in Japan’s method, and only added to the target amount. With this approach, the calculation for achieving the 2035 target not only allows for the increase in absorption during the 2013–2035 period to be counted, but also includes the total absorption up to that point, in addition to the emissions reductions.

The government explains that the gross-net method is recognized under international rules. Indeed, under the Kyoto Protocol, some countries used this method, but it is now hardly used among developed countries. The Climate Action Tracker, an independent think tank initiative that evaluates the NDCs of various countries, criticized Japan's use of the gross-net method in its review of Japan's NDC, stating that it "undermines the objectives of the Paris Agreement"³.

While the government's proposal does not specify how much absorption is estimated for 2035, the actual figures since 2013 have been around 50 to 60 million tons per year. If this amount is counted, the necessary reduction rate of emissions to achieve the government's proposal, which was a 53% reduction based on 2019, would become 49%⁴.

Thus, while the government proposal may seem to align with the IPCC's suggested 60% reduction by 2035 at first glance, when evaluated against the IPCC's 2019 standard and compared using the same concept of emissions (gross-to-gross), it remains at a 49% reduction.

The Government's Proposal Fails to Fulfill the Responsibilities of a Developed Nation 

As shown in Table 1, the IPCC’s suggested 60% reduction corresponds to the median (49–77%) of pathways that limit global warming to within 1.5°C with less than a 50% probability. The government may believe that a 49% reduction just barely falls within this range.  

However, it is crucial to remember that this is a global target for emission reductions. Developed nations, which have historically emitted large amounts of GHGs, are expected to aim for reductions higher than the global average. According to the Climate Action Tracker, Japan, as a developed country, should target an 81% reduction in emissions by 2035 compared to 2013 levels (net basis; 78% gross). This translates to approximately a 72% reduction compared to 2019 levels⁵.  

On January 20 next year, the Trump administration, which is expected to turn its back on climate action, will take office in the United States. While climate initiatives will continue domestically through the efforts of state governments, cities, and local governments rallying under "America Is All In," it is unrealistic to expect the Trump administration to play the international leadership role previously held by the U.S. federal government in the fight against the climate crisis. In this context, Japan’s responsibilities as a developed nation, alongside the EU, the UK, and Australia, will become even more significant. An NDC that only meets the bare minimum of the IPCC’s global reduction range cannot enable Japan to lead, let alone, follow the world in climate action.

What We Need Now is an Ambitious NDC and Accelerated Expansion of Renewable Energy and Energy Efficiency

At COP29, UK Prime Minister Keir Starmer garnered attention by announcing an increase in the country’s reduction target to 81% compared to 1990 levels. One key factor enabling this ambitious goal is the complete phaseout of coal-fired power, achieved this September, made possible by the significant expansion of renewable energy. The share of renewables in the UK’s electricity supply, driven by wind power, is approaching 50%. The Labor Party’s manifesto, led by Prime Minister Starmer, includes highly ambitious targets: doubling onshore wind, tripling solar power, and quadrupling offshore wind by 2030.  

In contrast, the previous Conservative government announced a strategy to supply 25% of electricity from nuclear power by 2050. However, nuclear power's share has been declining annually, reaching a historic low of 13% in 2023.  

In Japan, where renewable energy adoption has lagged and energy efficiency efforts have stalled, emission reductions have not been "on track" at all. What is urgently needed now is to set ambitious NDCs and align them with an accelerated energy transition toward decarbonization, outlined in a comprehensive energy plan.

Given that the revised energy plan targets 2040, constructing new nuclear power plants is unfeasible, as the government itself explains that such projects require a lead time of 20 years. Even achieving the current 2030 goal of 20–22% electricity from nuclear power appears challenging, especially as aging reactors continue to deteriorate. Setting higher targets for nuclear power in 2040 than in 2030 is simply unrealistic.

Japan’s decarbonization can only be realized through the maximum acceleration of renewable energy expansion and energy efficiency improvements. In light of the escalating climate crisis, the Japanese government is strongly urged to propose NDCs that fulfill its responsibilities as a developed nation and to formulate and implement a practical energy transition strategy to achieve them.