People can still be environmentalists if they drive, fly and eat meat, the leader of the Green Party has said.

Zack Polanski, who was elected in September and has overseen a surge in party members to a total of 184,000 by mid-December, said that too much onus was put on individuals tackling climate change rather than action by companies and governments.

“There is far too much focus on individual responsibility,” he said. “Shell and BP in the Seventies and Eighties knew what they were doing to the planet through their actions, so they created the idea of the carbon footprint to move the focus away from systemic change from governments and businesses and focus on individual responsibility.”

AKIRA SUEMORI FOR THE TIMES

Polanski, who is a London assembly member living in the capital, is vegan and does not fly or drive. “I have the privilege and the time to be able to make those choices,” he told The Times. “Someone can be an environmentalist and still not be able to make those choices.

“Because you can care about the planet but still need to drive your kids to school because there’s not an alternative option that’s affordable.”

Polanski has led the Greens to almost level with the Tories in polling and ahead of other parties among young voters, powered in part by his social media presence. The politician said that he was spending about an hour a day personally replying to people on social media, including on Instagram, where he said his posts had had 29 million views in a month. He recently celebrated his podcast, Bold Politics, hitting a million plays a month.

However, he said that it was not just the medium but his message that was resonating with people. At an event in November where the naturalist Chris Packham and scientists spoke of the dangers of climate change to an audience of about 150 MPs and peers, and celebrities from Jarvis Cocker to Jennifer Saunders, Polanski received the biggest cheer of any speaker.

“I think that message, first and foremost, is a message of hope,” he said.

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There is unease among some in his party about environmental issues being less prominent in his public comments, but Polanski rejected the idea that he was not talking about green issues.

“Nothing matters more than the environment,” he said. “So it’s nonsensical to ever suggest that the Green Party doesn’t care about the environment or it’s not one of our number one priorities.

“What has changed is the way that we talk about it. If people listen to me for more than 30 seconds, the environment is there. It’s just [that] the first thing that comes out of my mouth is always about bills and cost of living.”

After the bump in Britons intending to vote Green, he is rethinking his campaign goal of winning 30 to 40 seats in the next general election, up from the present four. “It’s an active conversation,” he said.

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If a coalition government was formed with the Greens, Polanski said his party’s longstanding opposition to nuclear power would see it try to block a fleet of “mini” nuclear power plants being developed by Rolls-Royce.

However, he would not be drawn on blocking large reactors already under construction at Hinkley Point in Somerset and Sizewell in Suffolk, saying the decision should be deferred to local citizen’s assemblies.

Polanski said that Labour would “lose all credibility” on climate change if it gave a green light to Rosebank, a major oil field that was licensed under the previous government. “The only reason why you’d make this decision on Rosebank [approving it] is because you’re in the pockets of fossil fuel companies,” he said.

Polanski at the party’s conference in Bournemouth in October

FINNBARR WEBSTER/GETTY IMAGES

Instead, Polanski said, Britain should be investing in wind and solar power projects owned by local people. “I believe we have the creeping rise of fascism in this country, and I think community energy is one of the tools — not the only tool — to be able to challenge that,” he added. “One of the reasons why we’re seeing people move to right-wing or even far-right ideas is because they feel like politics is being done to them rather than with them.”

The Greens leader said that he wanted to work closely with farmers as they were vital for food security and nature. He said that it was an “open question” as to whether the Greens in government would keep Labour’s reforms to end an exemption from inheritance tax for farmers, which has triggered protests and anger.

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In addition to nationalising water companies, Polanski said that the Greens in power would be interested in giving rights to rivers to help clean them up, something the nature writer Robert Macfarlane has called for. “I’m really interested in the rights of nature campaign,” Polanski added.

In the meantime, he is learning to cope with the “weird” experience of being recognised in shops and being stopped by other cyclists for selfies. “I’m finding it very surreal that just going to the supermarket has become an event,” he said.