From Japan to the world: Artificial photosynthesis can illuminate global solutions

Artificial photosynthesis represents one of humanity’s most ambitious scientific frontiers — an effort to replicate the process that has sustained life on Earth for billions of years. Using only sunlight, water and CO₂, this technology seeks to generate fuels and materials in ways that could redefine our energy systems.

Japan has been pursuing a broad portfolio of climate technologies — from thin-film photovoltaics to energy-saving semiconductors — to tackle the climate crisis and maintain global competitiveness. Among these efforts, artificial photosynthesis deserves particular attention because it produces clean fuels and holds the promise of actively removing carbon from the atmosphere, offering one of the few truly negative-emission pathways available to the world.

I have personally dubbed this initiative the 'Japanese Apollo Project.' It is a grand endeavour designed to address Japan's challenges, but it will also be applied to those that face the whole world. The Japanese Apollo Project seeks to artificially replicate the process of photosynthesis, transforming the world's abundant sources of carbon dioxide and water into organic compounds using solar energy.

The name carries a double resonance: it evokes Apollo, the Greek god of the sun and recalls the US Apollo Space Program — a symbol of human determination to achieve the seemingly impossible. Artificial photosynthesis embodies this same spirit; it harnesses the power of the sun to change humanity’s trajectory.

The greatest challenge the world faces today is climate change. The Intergovernmental Panel on Climate Change, after 30 years of effort and the combined wisdom of scientists worldwide, has confirmed beyond doubt that global warming is real. Tackling climate change is, therefore, an obligation for all humanity.

Recent years have shown us its devastating impact — torrential rain, hurricanes, wildfires and, in Japan, record numbers of heatstroke alerts. Last year, global average temperatures rose 1.5°C above pre-industrial levels. It's vital we take steps to mitigate and adapt to climate change now.

Energy underpins economic activity, yet its use has driven atmospheric CO₂ from 280 ppm before the Industrial Revolution to 430 ppm today. In Earth’s 4.5-billion-year history, CO₂ levels were once as high as 96%. Through photosynthesis, life gradually balanced atmospheric composition to its current form. But humanity’s accelerated fossil fuel use over just 250 years — equivalent to 1.75 seconds if Earth’s history were compressed into a single year — has destabilized this balance.

The Earth receives vast amounts of solar energy — enough in a single hour to meet all of humanity’s annual energy needs. Plants use only a fraction of this through photosynthesis, evolving over billions of years to sustain life. Replicating this process artificially is difficult, but not impossible.

With energy demand surging, accelerated by the rise of artificial intelligence and data centres, renewable energy alone will not be sufficient to power the Earth. Artificial photosynthesis offers a transformative solution: generating fuels and materials directly from sunlight, water and CO₂.

As Minister of the Environment, I convened the Study Group on Early Social Implementation of Artificial Photosynthesis to chart a path forward. On September 2, 2025 we released a roadmap that sets out the technological, economic and societal challenges, as well as milestones for 2030, 2035 and 2040.

The vision is clear. We need:

By 2030, partial social implementation of artificial photosynthesis.

By 2040, mass production of base materials and high-value substances.

The roadmap identifies advances in electrocatalysis and photocatalysis as critical. It also calls for financial support for demonstration facilities and a platform for collaboration among industry, academia and government.

Artificial photosynthesis is already being undertaken. It can produce valuable compounds, such as fragrances, using only sunlight, water and CO₂, but the costs make it impossible to do this on an industrial scale. The true breakthrough will come when ethanol can be produced at a price equal to or lower than that of fossil fuels. Achieving this will enable a new energy source and active removal of CO₂ from the atmosphere, a genuine mitigation measure against climate change.

The hope is that, beyond climate solutions, artificial photosynthesis will revitalize Japan’s economy. In 2000, Japan ranked second globally in GDP per capita. But by 2024, we had fallen to 38th. With an ageing and shrinking population, raising productivity is essential to sustain social welfare and economic security.

Innovation is the key driver of potential growth. If ethanol from artificial photosynthesis becomes cheaper to produce than bioethanol or gasoline, global demand will be enormous. Since CO₂, water and sunlight are universally available, production facilities need not be confined to Japan. This positions artificial photosynthesis as a global growth engine and one that could generate entirely new industries across continents, from Africa to Asia, while reducing geopolitical tensions rooted in fossil-fuel dependency.

Just as the US Apollo Space Program spurred unexpected innovations across industries, Japan’s Apollo Project will trigger breakthroughs beyond energy, fostering entirely new technologies and industries and ultimately boosting Japan’s productivity and competitiveness. Its broader significance lies in catalyzing a worldwide shift towards sustainable prosperity, where climate stability and economic dynamism reinforce each other.

Japan’s technological capabilities in artificial photosynthesis are at the same level as US space technology at the start of the Apollo Space Program — world-leading, but still far from full realization. With sustained effort and the right investments, the timeline to commercialization could be accelerated from 2040 to 2035.

This requires national commitment, potentially to the order of ¥1 trillion ($6.78 billion) annually, equivalent to what the US invested in the Apollo missions (adjusted to today’s values). Such an investment will enable Japan to become a global energy-producing nation through artificial photosynthesis. And, help close the emissions gap identified by the IPCC and provide the world with a scalable, negative-emission technology essential to meeting the Paris Agreement’s temperature goals.

The Japanese Apollo Project is a bold and necessary national mission — one that can raise Japan’s growth potential, restore its place in global leadership and, most importantly, accelerate the world’s transition to a climate-safe and economically resilient future.