The Russian invasion of Ukraine has drastically changed the global energy situation, upping the urgency to pursue decarbonization and still ensure a stable energy supply.

Japan has started facing problems of an unstable fossil fuel supply and soaring energy prices.

In the upcoming Upper House election, the ruling coalition and some opposition parties are pushing hard for restarting idle nuclear power plants. Depending on the outcome of the election, the nation's energy policy may change considerably. Voters need to think very carefully.

From a long-range perspective on energy security, the importance of domestic renewable energy sources continues to grow.

The lessons we learned from the Fukushima nuclear disaster 11 years ago must never be underestimated. While action is needed to address immediate needs, we must not lose sight of where we want our society to go.

FOCUS ON EXPANDED USE OF RENEWABLES

As scientific proof of global warming continued mounting, decarbonization became an accelerated trend in various nations. Reducing the use of coal in particular--a major generator of carbon dioxide--came to be seen as a matter of utmost urgency.

Since the Russian invasion of Ukraine, however, natural gas and oil supply chains have been badly shaken, forcing nations around the world to review their energy policies.

Japan, with its low energy self-sufficiency rate of only 10 percent, has been impacted. A recent record heat wave caused a power crunch. To secure a stable supply of electricity, reform of the supply system is urgently needed.

Many political parties are emphasizing a stable power supply for now in their election campaign platforms. But they remain vague on nuclear power generation and other core election issues, leaving the undeniable impression that they have not thought everything through.

What each party needs to do is to present its vision of a carbon-free society in 2050 and offer a carefully-planned strategy that differentiates short-term actions from mid- to long-term undertakings.

Dependence on renewable energies will be the key to realizing a carbon-free society and a stable energy supply. The use of renewables can be expanded considerably, and their prices will gain a greater competitive edge as the costs of fossil fuels continue soaring.

At least on their party platforms, all the parties are effectively in agreement that the development of renewables is their top priority.

But to accelerate this trend, certain issues must be addressed first, such as to further bring down the costs of renewables, make offshore wind-generated power and storage batteries more readily available, reinforce the grid and introduce a carbon tax.

The parties should compete on specific policies, including those for promoting technological development and reviewing the current systems.

NEED TO VISUALIZE 'EXIT'

Even with all the above attempts, however, it will not be possible to immediately achieve a new system that relies primarily on renewables.

In keeping with the progress of the utilization of renewables, thermal and nuclear power plants need to be decommissioned in stages, starting with the oldest, so that society can steadily reduce its dependence on conventional methods of power generation.

In the event of a supply crisis, it may become necessary to minimize its impact on society by reverting to those conventional methods for as long as necessary.

But even in such an eventuality, it is crucial that the situation be understood as strictly temporary, and that the "exit" through which society will eventually return to its normal state be clearly indicated.

In the meantime, what are we to do about nuclear power generation? Recent developments have raised the decibel levels of calls to speed up the restart of nuclear power plants.

The reality, however, is that plants that have not yet resumed operation cannot be relied on this summer and coming winter, because the Nuclear Regulation Authority is still screening them or having necessary work done on them. To ignore the rules of the NRA would be out of the question.

But what about the plants' mid- to long-term prospects?

Nuclear power plants do not generate carbon dioxide. And if their existing facilities are used, the immediate cost of power generation will go down.

But if a new plant is to be built, the government's cost estimates for 2030 show that industrial solar power generation will be cheaper. In other words, nuclear power generation offers only limited economic advantages.

One thing that must never be forgotten is the catastrophe that resulted from the 2011 core meltdowns at the No. 1 Fukushima Nuclear Power Plant operated by Tokyo Electric Power Co.

Once an accident has occurred, the ensuing damage will be tremendous and irreparable.

Because the mechanism that triggers natural phenomena--such as earthquakes, tsunami and massive volcanic eruptions--is still not fully understood, there is no realistic answer for how to be prepared.

The same goes for how to handle high-level radioactive waste. The prospects of finding disposal sites are dim at best, and Japan has the added problem of being unable to fully confirm the long-term stability of underground sites.

We also need to squarely face the risk of an armed attack on a nuclear facility, which became a reality with the Russian invasion of Ukraine.

NO PIECEMEAL RETURN TO NUCLEAR POWER

In its Upper House election campaign platform, the Liberal Democratic Party pledges to "make maximum use of nuclear power that has been confirmed to be safe."

But that does not seem to jibe with the nation's Basic Energy Plan, which calls for "reduced dependence (on nuclear power) as much as possible."

Will the LDP approve reconstruction of plants and new additions? If the party's intention is to leave its basic policy vague for the national election and later proceed piecemeal to restore nuclear power generation, that would be unforgivably irresponsible for a ruling party.

Also disconcerting are the LDP's calls to "improve the efficiency of NRA screening" and "consider a long-term (nuclear power plant) operation policy."

The highly independent nature of the NRA and the rule of "40-year operation, in principle" are the results of the lessons learned from the Fukushima disaster. Where safety is concerned, no compromise should ever be allowed.

In the meantime, the Constitutional Democratic Party and other opposition parties are advocating an end to nuclear power generation in their campaign platforms. But the parties should go into greater detail and be more persuasive in their arguments for prioritizing the use of renewables and what to do with thermal power generation.

Where coal-fired thermal power generation is concerned, Japan has been criticized by the rest of the world for refusing to set a deadline for ending it.

Many opposition parties are calling for the introduction of new technologies to reduce carbon dioxide emissions. But the bar is still quite high for the commercialization of such technologies, and the parties should discuss the issue in earnest.

Energy is an issue that is deeply embedded in our daily lives and the nature of our society, and the road to reforms will be long. We need to decide which party has the most reliable set of policies.

--The Asahi Shimbun, July 6