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Japan bets on Wattway

Special issue : n° 177 - On the Roads of the Future

Politique Internationale — A few words of introduction about TOA Road Corporation…

Takashi Matsumura — TOA Road is one of the oldest companies in Japan specialising in road building. Founded more than 90 years ago, TOA is known in particular as the first company to manufacture and sell asphalt emulsion. The emphasis on roads came a little later during Japan’s post-war reconstruction, which was synonymous with solid growth in infrastructure sites. And the results lived up to the task: TOA Road established itself as a key industrialist for manufacturing road materials and road building.

P. I. — Can you go into a little detail about your products?

T. M. — Modified asphalt and asphalt mixture are our two main products, accounting for about half our sales on the domestic market. But we have also developed other segments: cement and asphalt emulsions, and surfacing materials for landscaping and sports installations. For example, we use the emulsions technology on the Shinkansen railroad, the Japanese high-speed train. As for surfacing materials, we supply all the velodromes in the country. Suffice it say that TOA Road covers a wide range of activities. In addition to these products, we are active in road works and civil engineering for most types of infrastructure: roads, airports, railways and sports grounds – and even for more targeted facilities such as tennis courts. Added to this are our consulting missions, which account for a large part of our industry.

P. I. — There is a danger that people will object that this broad range of activities is not very carbon-efficient.

T. M. — We are perfectly aware of the environmental problems. That is why, for several years, we have been stepping up technological innovations for reducing the CO2 footprint: roadways at ambient temperature, heating at medium temperatures and technology for regenerating materials. We are making constant progress; in fact, we are currently testing a surface substitute that is entirely of plant origin.

P. I. — When did TOA Road start taking an interest in solar roads?

T. M. — The foundations were laid a little over two years ago when work began on the Wattway system technology. Last year, we joined forces with Colas Japan to submit a joint bid for an expression of interest issued by the Japanese government on: New technologies for improving the resilience of Michi no Eki (“roadside stations”) in the event of disaster. The wind is favourable because another show of interest is coming with the public authorities determined to assess the durability of solar road surfacing. We should be candidates once more with Colas Japan. In the meantime, it is not just a matter of making progress in solar road technology and coming up with tangible improvements: we also need to continue raising awareness among all stakeholders about Wattway’s potential. It is worth noting that in June we started to sell the Wattway Pack throughout the country (Editor’s Note: a readymade solution that ensures the autonomy of electrical equipment on the sides of highways).

P. I. — In a country like Japan, how long will it take for solar roadways to be ramped up?

T. M. — It is never easy to set a specific timetable. I don’t know whether it will need time or not, but I think solar roads will probably take root long-term in Japan, quite simply for reasons relating to energy policy. If we go back in time a little, we can see that the Japanese have a very ambivalent feeling about nuclear power. This can be explained firstly by the destruction of Hiroshima and Nagasaki. However, faced with the scarcity of energy resources in the country, Japan set out to develop the civil atom in the post-war years. To reconstruct the country, all available energy sources had to be harnessed. And then, the Fukushima disaster happened in March 2011: from one day to the next, nuclear power stations stopped operating, and reliance on fossil energies grew automatically. Increasing the use of fossil energies was undoubtedly inevitable, but it could only be temporary: history shows we are heading towards a drastic reduction in CO2 emissions.

P. I. — More than 10 years have passed since the Fukushima nuclear disaster: are we now heading towards a rebalanced energy mix?

T. M. — In 2021, Japan promised the international community that it would stick to the 2050 carbon neutrality goal. Although the gradual resumption of the nuclear industry is part of this framework, the Japanese population is unwavering in calling for electricity production to be boosted from renewable sources. Photovoltaic fulfils this aspiration, but not just any photovoltaic. In effect, conventional photovoltaic faces significant obstacles: Japan is a small, largely mountainous country where it is difficult to prepare the ground to build solar energy plants. Moreover, public opinion is increasingly hostile, both for environmental reasons and because of geological threats – especially landslips like last year’s in the Kanto region. There is also the question of safety when it comes to installing solar panels on roofs: these metal structures, especially if they are heavy, cannot be mounted on buildings built to resist earthquakes. In general, we need to bear in mind that Japan is a country prone to natural disasters.

P. I. — In the face of this rise in natural disasters, what energy schemes should be prioritised?

T. M. — Well, the government is now promoting a “national resilience policy”. The call for expressions of interest mentioned earlier – New technologies for improving the resilience of Michi no Eki (“roadside stations”) in the event of disaster – comes under this framework. The aim is to maintain continuity in electric power in the event of a natural disaster. Typically, it is imperative to guarantee the functioning of communications systems on an isolated site. In other words, the solar Wattway surface is perfectly compatible with this requirement: it is a technology that is ecological, guarantees the best use of space and is resistant to natural disasters. To reiterate what I said in my opening comments: Wattway has the potential to provide an efficient solution to Japan’s energy issues. In 2025, the city of Osaka will host the World Expo, an event where the focus will be firmly on environmental challenges and the work underway to respond to them. We already consider Osaka 2025 to be a critical stage in Wattway’s development in Japan.