Just a few years ago, politicians and environmental groups in the Netherlands were thrilled by the early and rapid adoption of “sustainable energy,” achieved in part by coaxing electrical plants to use biofuel — in particular, palm oil from Southeast Asia.

Spurred by government subsidies, energy companies became so enthusiastic that they designed generators that ran exclusively on the oil, which in theory would be cleaner than fossil fuels like coal because it is derived from plants.

But last year, when scientists studied practices at palm plantations in Indonesia and Malaysia, this green fairy tale began to look more like an environmental nightmare.

Rising demand for palm oil in Europe brought about the clearing of huge tracts of Southeast Asian rainforest and the overuse of chemical fertilizer there.

Worse still, the scientists said, space for the expanding palm plantations was often created by draining and burning peatland, which sent huge amounts of carbon emissions into the atmosphere.

Considering these emissions, Indonesia had quickly become the world’s third-leading producer of carbon emissions that scientists believe are responsible for global warming, ranked after the United States and China, according to a study released in December by researchers from Wetlands International and Delft Hydraulics, both in the Netherlands.

“It was shocking and totally smashed all the good reasons we initially went into palm oil,” said Alex Kaat, a spokesman for Wetlands, a conservation group.