Jonathon Porritt: Economic growth at all costs is just not sustainable

Governments still adopt increases in economic growth as the overarching imperative and everything else really plays second fiddle. The consequence of this is that an awful lot of other policy areas tend to get downgraded. Our fear is that the costs of generating prosperity in consumption-driven economic growth actually outweigh the benefits of the growth itself.

Greenhouse-gas emissions, the impact on people's health of increasingly unhealthy lifestyles, the impact on communities, which suffer if we put economic growth before all else – these are all big costs. And they all lead to negative impacts on people's lives.

The Government has put in place an impressive set of foundations to produce a more sustainable society, but at the same time we've seen a lot of indicators heading in the wrong direction. We have more negative impacts than we have positive impacts, so the overall report card would read good progress in some areas but, overall, not a good picture.

I feel some disappointment because I would have wanted to see faster progress. The Government will be launching an Energy White Paper on 13 July, which is the sort of thing they could, and should, have done four or five years ago. And Lord Adonis, the new Secretary of State for Transport, came back recently from a visit to mainland Europe full of praise for integrated transport polices around cycling and walking. But this is basic stuff and we could have been doing what other countries have done 10 years ago.

We have a terrible record of leading the world on rhetoric and then failing to deliver in our own backyard, and that's particularly true on climate change. The new Climate Change Act is a significant step forward but I doubt that the Government is going to be blowing its trumpet very loudly about its overall record on sustainable development at the next election because I think it knows it would be on very dodgy ground.

It takes quite a long time to turn an economy from unsustainable economic growth to genuinely sustainable economic development. That is the journey we're on. I am confident that we're moving in the right direction; it's just happening much too slowly.

I'm still a member of the Green Party and I'm anxious to take on a more campaigning role. We've wasted too much time, and people know we need to move a lot faster. I'm looking forward to playing a role in ensuring that happens.

Jonathon Porritt is the outgoing SDC chair