Jeremy Corbyn has called the Labour leadership campaign the "most exciting period" of his life ever, as the deadline for voter registration draws near.
Speaking at the launch of his energy manifesto, Mr Corbyn called on his supporters to "harness the excitement and optimism" of his campaign, and consider the party's failure in May when deciding their vote.
He said: "Think about the role our party can play, have a think about why we didn't succeed in winning the last general election. I believe fundamentally because we weren't offering a clear enough economic and social alternative. Whatever happens on September 12 the cork is out the bottle, the candle is burning bright, the ideas are shining and there is a change in the air."
While Mr Corbyn conceded he didn't have a large number of rich friends himself, he reiterated his comments in this morning's Independent newspaper that rich people would be happier paying more tax, and added "all of us are vulnerable".
He said: "I would say to people that are very, very rich, I'm sure you would be happy to contribute a little bit more to ensure fellow citizens live a bit better.
"All of us could have a car crash, all of us could have a road accident, all of us could suffer mental illness, all of us could suffer grave disability or life threatening conditions. Then we need the health service, then we need social services, then we need emergency services."
Speaking at the Camley street national park, a nature reserve in central London, Mr Corbyn promised to make "radical" commitments to the energy sector and pledged a "fundamental shift in UK energy thinking" if he is made Labour leader.
"I would bring together a coalition of the majority, to move on from wasteful, polluting and unequal economic approach to our environment and instead democratise our economy to reduce inequality and promote sustainable development within the Earth's resource limits."
Addressing the news today that Labour membership numbers are rising by the fastest rate in 64 years, the backbench MP said the news was positive, but he only wants those genuinely interested in the future of the party on board.
Mr Corbyn said: "It is a point of joy that so many people, particularly young people want to join the Labour Party and become registered supporters. But I want them to be genuine supporters and I want them to stay in the party."