As he has throughout his bid for the presidency, Biden emphasized a shift to renewable energy, saying his $2 trillion clean economy jobs program would create more than 18 million jobs.
"The oil industry pollutes," Biden said. "It has to be replaced by renewable energy over time. ... I'd stop giving federal subsidies to the oil and gas industry."
Trump, sensing an opportunity to appeal to voters in battleground states with strong fossil fuels ties, pounced on the comment.
"That's the biggest statement," Trump said, turning to look directly into the camera. "Will you remember that Texas? Will you remember that Pennsylvania? Oklahoma? Ohio?"
Trump also reiterated a trope of the fossil fuel industry, calling a shift to renewables a "pipe dream" and saying that wind turbines kill "all the birds." In a muddled response, he misleadingly suggested that the construction of wind turbines "is more than anything that we are talking about with natural gas."
Biden responded, "Find me a scientist who says that."
Trump also attacked Biden's climate plan, falsely saying it would cost $100 trillion.
"They want to take buildings down because they want to take bigger windows and make them smaller windows," Trump said, referring to the proposal. "Little tiny windows and many other things."
The proposal says nothing about shrinking windows.
Trump also attacked Biden on his statements on fracking and natural gas, falsely accusing the Democratic candidate of supporting a ban on fracking and changing his position to court voters in Pennsylvania, a natural gas-intensive and critical swing state, won narrowly by Trump in 2016.
Biden corrected Trump, saying he would only ban new oil and gas permitting on public lands, but supports fracking elsewhere as necessary while the country transitions to a clean energy economy — a position that has been criticized by climate advocates.
Biden framed addressing climate change as an ethical matter and part of a broader shift to rejoining global peers
"We have a moral obligation to deal with it," he said. "We don't have much time.
"We're going to choose science over fiction. We're going to choose hope over fear," Biden said, saying that he'd advance an economy "motivated" by clean energy. "We can grow this economy," Biden said. "What's on the ballot here is the character of our country."
Environmental activists largely applauded Biden's performance, even as many vowed to push him to take bolder steps.
"We are committed to holding a Biden administration accountable to stop fracking and protect our communities," said 350 Action North America Director Tamara Toles O'Laughlin. "Indigenous, and communities of color continue to bear the brunt of Donald Trump and his fossil fuel lies. It's time for a just transition for workers across the industry. The planet can't take four more years of Trump's deadly mismanagement and plain incompetence."
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