Japan struggles for balance in pivot to renewables
Infrastructure constraints confound efforts to close thermal power plants
Like many countries, Japan has to juggle the current reality of power supply with its net-zero goals. While there’s no going back to the primacy of fossil fuels, Japan is taking small steps to resolve immediate energy issues and hoping for a lucky break in future ‘dream’ technologies to meet its 2030 and 2050 emissions reduction commitments — but challenges abound, writes Mayumi Watanabe.
The expansion of Japan’s renewable energy sector has resulted in transmission capacity bottlenecks, causing solar output curtailment. At the same time, moving to a system in which thermal power plays a supporting role to renewables throws up technical and economic issues.
In June, the government hopes to shed light on how those issues might be resolved by publishing a new Clean Energy Strategy. It will act as a roadmap for how to achieve the 46% carbon reduction from FY2013 levels Japan has promised, a vow based on a doubling of renewables’ share and a halving of thermal capacity.
The Strategy will need to rally the entire energy sector so that disparate actors learn to work together. Without that spirit of cooperation, Japan faces an unnecessary waste of time and resources, and the clinging on to short-term fixes, such as extending the life of half-century old thermal units to survive peak demand periods.
Coal saves Tokyo, again
As the climate becomes more extreme, major population and industrial hubs like Tokyo and Chubu face stronger cold spells and summer heat. In recent years, these regions have weathered such periods largely thanks to old coal, gas and oil-fired plants commissioned in the 1960s and 70s. Without these plants, lights would go off.
Whenever supply margins tighten, for example when LNG becomes scarce or snow blankets Tokyo and solar generation collapses, power systems across several regions ramped up thermal output to avoid blackouts.
Yet, the segregation in Japan’s grid (which operates at two distinct frequencies) means that even help from other regions is limited by the narrow volumes that can be moved nationwide.
Since the January 2021 LNG supply crunch, METI has been slowing plans to scrap thermal plants. If utilities decommission aging equipment as standard, Japan could lose 16.77 GW of thermal power by 2030. Most are oil-fired. Coal capacity, however, will increase by 1.87 GW by 2030.
METI’s actions to slow decommissioning may help for a few years, but no longer. Japan’s coal-fired plants alone could eat up the CO2 allotment for the power system in the 2030 emissions plan.
The other side of the problem
While METI tries to keep older thermal capacity afloat to meet today’s needs, national energy policy calls for a wider rollout of renewable energy. However, as more solar and other intermittent energy sources hook up to the grid, they are not integrated in an efficient manner.
Kyushu area is a good example. Since 2015, solar operators have been asked to cut output as the area’s power generation exceeded demand and transmission capacity.
Kyushu Electric expects that from April 2021 to March 2022, some 580 GWh of solar power will be curtailed. The forecast for the next fiscal year is worse: 730 GWh of solar generation to be curtailed in Kyushu, about 440 MWh in Shikoku and 976 MWh in Okinawa.
Without a solution, the trend of wasting energy will only exacerbate as Japan moves to establish an offshore wind industry, with licenses for 10 GW of capacity to be awarded by 2030.
The most promising offshore wind zones are in Japan’s north, the Tohoku and the Hokkaido regions, which have no power shortages. In fact, the Hokkaido projects have yet to progress to tender stage because the regional power transmission operator says there’s no room in the local grid.
The solution for Kyushu, Tohoku and Hokkaido is to send excess power to regions such as Tokyo and Chubu which face a dearth of energy. That will require expanding power transmission capacity, a process expected to take 10-15 years and require massive investments.
In the short-term, local grids in areas with excess electricity from renewables will ask thermal power plants to operate at lower run rates, giving solar and wind energy more space. But power grid operators say the best way to harmonize disparities is on a central basis, rather than a micro or area basis.
Japan bets on ‘dream’ technologies
METI hopes technology can resolve the disconnect between thermal power-backed energy security and underutilized renewable resources. The biggest potential is seen in enhanced storage batteries and in utilizing redundant renewable power to make hydrogen, ammonia and synthetic fuel to be used for co-firing of coal power plants.
These ambitions are supported by R&D financing from the Green Innovation Fund. This June, PM Fumio Kishida is expected to announce a Clean Energy Strategy with more details, building on the scenario stated in the 6th Basic Energy Plan.
Experts, however, warn that it’s risky to place the country’s future in technologies that don't yet operate commercially. An example of how this can go wrong occurred two years ago. METI placed much hope in Integrated Gasification Combined Cycle coal plants, which boasted 46-50% energy efficiency and were heralded as miracle technologies. Two IGCC plants came online in 2020 but following multiple technical issues in 2021 they were excluded from the 2022 power supply plan.
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The goal that Kishida’s government wants to achieve with the Clean Energy Strategy is to cut power sector emissions to 219 million tons/year, from the present 422 million tons/year. But for that to happen the deeper underlying issue that has to be resolved is how the traditional energy system can work together with the new one that’s based on variable renewable energy.
Unless these two disparate systems can find a way to coexist and cooperate over the next 10-20 years, the overall goal of net-zero by 2050 will be nothing but a pipe dream.
This article first appeared in Japan NRG Weekly, a Tokyo-based platform for information and analysis on energy and electricity markets in Japan. Reproduced here with permission. Find out more at www.japan-nrg.com.