Patent filings in energy exceeded other sectors, IEA says

China, Korea, and Japan dominated global energy patent filings.

One in ten global patents relates to the energy sector, exceeding patent counts for chemicals, pharmaceuticals, and transport, according to a report from the International Energy Agency (IEA).

China, Korea, and Japan led global energy patent filings, with batteries accounting for 40% of energy innovation activity in 2023, reflecting a shift towards energy security and industrial competitiveness.

China increased its share of lithium-ion battery patents and expanded its presence in energy storage and industrial efficiency, whilst Japan focused on batteries, perovskite solar cells, hydrogen-based fuels, and fusion energy, IEA said.

It also listed 150 technology updates, including sodium-ion batteries, solid-state air conditioning, and next-generation geothermal systems. Perovskite solar cells comprise 70% of solar cell patents by material.

Global public energy research and development spending reached $55b in 2025, a 2% decrease from the previous year. Corporate research and development growth also slowed to 1% in 2024.

Venture capital investment in energy start-ups dropped to $27b, whilst artificial intelligence ventures received 30% of global venture capital funding in 2025, the report said.

European public energy research intensity reached 0.08% of gross domestic product, whilst the United States accounted for half of energy venture capital.

Government funding supported floating liquefied natural gas and lithium-ion batteries. Evidence shows energy innovation delivers economic and security benefits over decades through fuel savings and lower equipment prices, according to IEA.