Liberal Democrats have been urged to rule out the building of any more nuclear power plants.
Mr Baker said sustainable energy sources were the future
The party's environment spokesman, Norman Baker, said there should be more use of renewable energy sources, to cut carbon dioxide emissions.
Nuclear power was "enormously expensive" and should be dumped for "better long-term returns".
The party's conference in Blackpool also discussed bringing in a system of road user charging.
The Lib Dems want to reduce UK carbon dioxide emissions by 60% by 2050.
Mr Baker said: "The sooner we close the debate over nuclear power, the sooner investment in renewable can grow."
He added: "Climate change is the greatest threat facing the planet. A threat of such global proportions must be tackled through international action.
"The environment must be at the heart of government, not out on a limb."
The government has not ruled out building more nuclear power stations to help it meet carbon emission targets and plug the energy gap created by the closure of ageing plants.
Mr Baker said: "If we are comparing the effect on the landscape of wind farms and nuclear power, I know which one people would choose."
Meanwhile, the Lib Dem transport spokesman, Tom Brake, called for vehicle excise duty and fuel tax to be replaced by road user pricing.
He said: "The United Kingdom has the dubious honour of having the most congested roads in Europe.
"We find ourselves in a situation where our high streets come to a virtual standstill, our motorways go at a crawling pace.
"Without proper action, things will only get worse."