Ten years ago, Anna D'Arcy made a small, positive change at her students' union. This was the first of 250,000 actions carried out through Green Impact across the world. 

Anna D'Arcy was first part the student movement in the 90s, and she left education feeling confident that sustainability was mainstream in student politics.

She returned to university a few years later and was surprised to find the environmental movement had become a back seat issue again.

This is the story of the student who founded Green Impact.

What gave you the idea for Green Impact?

In my final year at university, second time around, the students' union opened a pizza place, and they gave you a box whether you were taking it away or not. I went there in the first week and ordered a pizza and sat in there, watching the queues, watched the cleaner go around with a black bag and shoving the pizza boxes in to it for disposal.

I did the mental maths. At minimum, 200 pizzas each lunch time, 5 days a week. That was 1000 pizzas boxes at least going in to landfill, then based on a 36 week university year at a minimum that was 36,000 pizzas boxes going into landfill just from this one place. I knew that the franchise had opened elsewhere at other unions in the county too.

I stood outside the students' union dressed as a pizza box, asking students to ask for a plate.

The students' union staff and the general staff and student population got right behind the issue. The union elections were also a few weeks away; this resulted in all the candidates coming to see me to find out more about the issue and unanimously all pledging in their manifestos to sort the issue out - a certain Spike Reid was elected as president and he and the staff team stuck to their word.

That's a great story about how simple campaigning can drive a positive change. But it wasn't just about pizza boxes though, right?

Right. I realised that there was a bigger issue a national picture that needed to improve. Students' time at a university is one of the last times they will get to be influenced before they go out into the world.

I felt NUS should be doing something - but what?

I know it's simplistic and old hat now, because there are so many green awards, but there were hardly any green awards or competitions at that time. There were two that I knew of and they were not even widely known about.

I thought of an awards scheme, that would evolve each year, being owned by the current student intake, improving each year and giving students some competition and reason to dress up and celebrate And the other thing I was very sure about was the NUS had to front it, to give out the right message.

So that night I had a very strong vision of an awards night with officers all dressed up, celebrating all the great things they had done and it being run by NUS and with involvement of The Ecologist; mitigating their negative impact and improving their positive impact; this was the goal and where the 'Impact' part of the name came from.

What was the moment you realised that it was becoming something transformative, and could make a national impact?

The first year was amazing, and the second year we had even more unions sign up. We got excited each year as applications closed to see the increase in numbers.

There are a few milestones when I realised I had successfully let my baby go and grow and that it had become something beyond and transformative, from the IEMA Accredited Auditor training and qualifications for the student auditors, to the movement of Green Impact into other arenas such as universities, local councils, health authorities even a fire brigade.

But thing I am most proud of and when it really hit home was when I got an email from NUS after they spoke to the Parliamentary Environment Committee last year, and were able to tell them that Green Impact an environmental accreditation and awards scheme in over 105 students' unions, and had clocked up 70,000 pro-environmental actions in that year alone.

What have you been up to in the ten years since?

For the first few years I assisted with the Green Impact audits alongside my masters' degree and working as an environmental consultant to business.

I worked with my children's schools on waste awareness and did talks to children about the pizza box issue, the beauty of the talk is that I would get 8 year olds to make up flat pack pizza boxes. 20 of them stacked is about the size of an average 8 year old. I would then ask 10 children to come and stand by the stack of 20 pizza boxes and it gave them a visual idea of what the size of 200 pizza boxes going into landfill each day would look like - they really got it and it sparked something off in them.

About 5 years ago, I relocated-to New Zealand to work for a regional council as their Business and Corporate Sustainability Manager; last year, I was shortlisted for the New Zealand Government Green Ribbon Awards - Public Sector Leadership Category for a sustainable procurement project with a $80 million annual spend...

Have you kept an eye on Green Impact?

Yes, very much so, I was involved in the first few years as a Green Impact Auditor but since then I have kept a motherly distant eye. I keep in contact with the team, who keep me in the loop. I am subscribed to the Green Impact updates and take a keen interest in how it is looking, who has won what, who is involved this year; I love hearing all the news of its progress.

As we look back on ten years of Green Impact, we're also looking to the decade ahead. How would you like to see the programme develop over the next ten years?

That is the beauty of the scheme: the students involved at the time will direct its evolution and you have to trust that they will develop it with the innovative, brave and unencumbered hearts that the student movement has.

I am still not aware of any such programme in the world that has achieved as much as Green Impact. The student movement is global and it would be great to see how this develops, to showcase and share this living breathing scheme to other countries.

The training, development and business partnerships is another area I would like to see progress; there are now a number of former Green Impact student auditors who have followed a sustainability career path because of their involvement in Green Impact - the more of those people out there in the world, the better.

And of course, my eldest daughter will start university next year and is already looking forward to being part of Green Impact, which is a real buzz for me.