Investments in a range of clean energy technologies are poised to increase in Southeast Asia over the coming decades, but growth really skyrockets if the world gets on a path of limiting Earth’s temperature increase to 1.5 degrees Celsius, according to a new report by the International Energy Agency.

Countries in this region, including Indonesia, Thailand and Vietnam, are still growing their economies and thus their energy demand is set to increase under all scenarios.

But outlooks diverge widely depending which pathway the world pursues: one that includes significantly more aggressive government policy that limits the Earth’s temperature rise to 1.5 degrees Celsius or another, less aggressive pathway that reflects countries’ current and announced policies.

Clean energy technologies increase in both scenarios, but demand for oil, natural gas and coal increase only in the latter, less aggressive pathway.

Among new energy technologies, batteries are set to increase the most, particularly in a 1.5-degree scenario.

Market size estimates include average market prices and sales of tradeable units of the core technologies listed, IEA says. This differs from investment or spending estimates that include things like installation costs.