This week, Nick’s letter is about his speech to the Green Alliance. It summarises what he said, but doesn’ t link to it. Just as well we put it in full here, then. The aim is to drive people to shiny new “Why I am Green” Nationbuilder site. 1329 people have already given their reasons. He’s losing no opportunity to explain why Ed Miliband’s energy price freeze just doesn’t cut it. He’s modified the language a bit, putting in a bit more detail, but is still describing it as the con that it is.

This week I made one of my most important speeches of the year. Miss it? I wouldn’t be surprised: it was on the environment – an issue that used to be the height of fashion across Westminster but has now fallen out of the political vogue.

I met with green groups so that they could hear direct, from me, that the Liberal Democrats are as committed as ever to the green agenda. Back when the Coalition formed, the Conservatives said they wanted this to be the greenest Government ever. We haven’t forgotten and every day we’re holding them to their word.

It doesn’t make for a particularly quiet life in Whitehall. To be honest, I think the Tories find it baffling. They’ve decided that there are no longer votes in green issues because people are too busy worrying about the economy – and they can’t fathom why we still care. And yet last month all of us sat to hear Sir Mark Walport, the Government’s Chief Scientific Advisor, set out the threat of climate change in the plainest possible terms. He said politicians need to stop asking if climate change is happening, or if humans are responsible for it. We need to get on with tackling it. What more do the doubters need?

You would, on this occasion, expect Ed Miliband to get it. He is a former Climate Change Secretary after all. But Labour’s populist promise to temporarily freeze energy bills would be a huge blow to our green commitments. Not only is it a con – with the energy companies bound to hike up prices before and after the freeze – but it would also massively undermine investment in our renewables industry, threatening clean energy and thousands of jobs.

So it’s up to us to keep pushing policies that protect our environment – whether that’s our 5p charge on plastic bags, cutting greenhouse gases, or getting more low carbon cars on our roads.

I’m green because I want to hand on the best world possible to our children and grandchildren – tell me why you’re green too.

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