LITTLETON, Colorado, Feb 19 (Reuters) - The fuzzy characterisation of bioenergy as a clean power source has fuelled its expanded deployment in global power systems in recent years, often as a replacement for coal in countries committed to cutting fossil fuel use in power production.

Bioenergy plants burn organic matter known as biomass to generate power, and are often lumped in with solar, wind and hydro plants as a form of renewable energy.

However, due to the rapid rise in the use of wood pellets as the main source of biomass in large power stations, the continued growth in bioenergy capacity poses a fresh climate threat as it potentially promotes further deforestation.

What's more, the United Kingdom and Japan have the largest bioenergy capacity pipelines under construction outside of China, which means that fully developed nations will play a key role in driving biomass use to new highs in the coming years.

GROWING PIPELINE

The UK and Japan have only a combined 10% share of currently operating bioenergy capacity, but account for nearly 30% of the bioenergy capacity under construction, according to Global Energy Monitor (GEM).

Japan's 1,200 megawatts (MW) and the UK's 875 MW of bioenergy capacity under construction fall short of the 3,400 MW at the same development stage in China.

However, those development totals will nonetheless lead to sharp rises in total bioenergy capacity in both Japan and the UK once construction is finished.

Japan's total bioenergy capacity is set to jump by 36% while the UK's capacity will grow by 20% once the new projects come online, GEM data shows.

Those capacity expansions are the largest among all major current bioenergy producers, and will serve to expand the clout of bioenergy plants within national power generation systems.

EXPANDING SHARE

Bioenergy power plants have been steadily increasing their share of electricity production in both Japan and the UK over the past decade.

In 2024, Japan's bioenergy plants accounted for a 6% share of total electricity output, while in the UK that share was 8%, according to data from energy think tank Ember.

In both countries, 2024 was the highest bioenergy electricity generation share on record.

In absolute generation terms, Japan's bioenergy plants produced nearly 46 terawatt hours (TWh) of electricity in January through October of 2024, which is up 7% from the

same months in 2023 and a record.

In the UK, bioenergy-fired electricity output was 18.8 TWh during 2024, which was the second highest total since 2021's record 19 TWh.

More significantly, the UK total was 41% greater than the bioenergy generation tally of 2023, due to a sustained climb in production late last year as bioenergy plants helped offset the halt in generation from the UK's last remaining coal plant.

EMISSIONS IMPACT

The growing volumes of bioenergy power production has yielded a commensurate swell in plant emissions.

In Japan, bioenergy plants discharged 10 million metric tons of carbon dioxide during January to October, which was up 7% from the same months in 2023 and the highest on record.

In the UK, bioenergy plants discharged around 4.3 million tons of CO2, which was just shy of the 2021 record of 4.4 million tons.

Those totals pale in comparison to the discharge from fossil fuel plants over those same period: Japan's fossil fuel-fired total was 330 million tons while the UK's was 41 million tons.

However, while fossil fuel use in both countries has likely already peaked, bioenergy pollution looks set to keep climbing, especially once new capacity projects reach completion.

What's more, significant deforestation in key woodland areas will likely take place to produce the biomass needed for the bioenergy plants in the UK, Japan and elsewhere, which will place an additional toll on regional and global climate systems.

Indonesia's ancient rainforests are the primary source of Japan's wood pellet imports, while the forests of Canada and the Unites States are the main suppliers wood pellets and chips in the UK.

That means that the impact trail of bioenergy plants in Japan and the UK will extend well beyond their international borders, and may drive additional climate change through the acceleration of deforestation in other parts of the planet.

The opinions expressed here are those of the author, a market analyst for Reuters.

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https://www.reuters.com/markets/commodities/uk-japan-bioenergy-capacity-plans-pose-fresh-climate-threat-maguire-2025-02-19/