An application to build a biofuel power station at Avonmouth, capable of powering 25,000 homes, has been refused by city councillors.
The plant, which would had been fuelled initially by palm oil, was attacked by critics who blamed the demand for palm oil for rainforest destruction.
The meeting was told the decision had to be made according to material planning considerations, not emotions.
But councillors went against advice from planners and voted 6-2 against it.
Legal officers reminded councillors they would have to justify their reasons if the company behind the application, W4B, decides to appeal.
More than 1,100 written objections were raised before Wednesday's meeting.
The Avonmouth plant was one of several plants around the UK under consideration; one in Weymouth has already been approved.
BBC West business correspondent Dave Harvey said Bristol's decision was being closely watched as there were several similar applications for biofuel power stations around the country.
"If Bristol's decision stands then local councillors have every right to consider the international environmental issues and not just the immediate local planning questions."