A “ONCE-in-a-lifetime opportunity”. That’s how some people described the independence referendum that electrified Scotland in 2014.

The day after the vote, it briefly felt like that really might be the case. Everyone who campaigned so hard for our country to gain the right to decide on its own future felt deflated, shattered and disillusioned. The votes were in, but for many people the result was crushing.

A year on from that day it’s clear that the debate isn’t over. Polls consistently show that rather than people’s hopes for independence being wiped out, they have grown stronger. Maybe that’s because some people have had time to reflect, and feel their reluctant No vote was a missed opportunity. Some others voted No because of the promise of deeper devolution, a promise which even Gordon Brown now believes is being broken.

But whatever the reasons, many people on both sides of the independence debate now recognise that 2014 wasn’t the end of the story. Scotland will ask itself the question again some day, and even those who sat uneasily together in the Better Together camp last year seem to understand that it’s a matter of when, not if.

The Scottish Greens campaigned for independence last year because we wanted a chance to make the radical changes needed to build a socially just, sustainable society. The victory of the No camp didn’t change these aspirations, which is why our party believes that when the time is right, Scotland should have a second independence referendum.

That question, of when the time is right, is an important judgment. Some people can’t wait to get started on a second campaign, while others want the debate to move on rather than simply seeing a repeat performance of the same arguments. In my view there are some key policy areas in which greater clarity will be needed, if people are going to reach a different view and give the decisive majority which would be desirable.

One of the issues most often discussed is currency. The SNP still holds to the view that the currency union proposal was the right one, and that it would still be the best option if Scotland was to opt for independence. But even those who agree should acknowledge that it takes two to tango. If we’re to have this debate again, it should be from a position of strength knowing that the groundwork has been done to create a Scottish currency which people can have confidence in. As others like the New Economics Foundation and Common Weal have shown, exploring alternative currency systems even in the context of devolution has real potential to allow Scotland to defend itself against austerity. This is an agenda which needs to be developed now, well ahead of any future referendum. That’s why this weekend the Greens are launching our own proposals for a crowd-funded research initiative on Scotland’s future currency.

Europe is also mentioned by many people as a potential game-changer. I remain confident that an independent Scotland would be welcomed into the EU, but if the rest of the UK votes to leave it will result in a worse context for an independence vote, not a better one. There would be even tougher questions facing us about retaining a Common Travel Area with a non-EU rUK, and about whether we could inherit the current UK terms of membership. So joining with others who want a progressive, social and environmental Europe instead of David Cameron’s free market version, and winning the referendum throughout these islands, will be hugely important.

The First Minister has said she never wants to experience the feeling she had the morning after the No vote again, and truth be told, neither do I. We need to make sure that a second referendum is only held once the Scottish people really want to have it.

The SNP have continuously said the next referendum should be decided by the people, not by politicians. It’s time to put some detail to that principle.

The Scottish Greens believe in democracy at local, regional and national level. We don’t need to rely on party politics to determine the timing for the next vote on independence. That’s why we’re proposing that new democratic ideas, such as a “citizens’ initiative”, should be considered as the means of deciding the timing. If a million of Scotland’s voters say they’re ready to see another referendum, surely this would be more powerful than the say-so of politicians alone.

So Greens will back that approach, putting the ball into the voters’ court. Meanwhile we’ll continue to hold the government to account, proposing transformational policies for the Scottish Parliament and setting out how more powers, and independence, could achieve even more.

Nicola Sturgeon: Scotland’s new spirit of hope is the legacy of an extraordinary independence campaign

The National View: Why we're still Yes ... and will fight on

Letters to The National, September 18: Should we 'move on' from the indyref and accept our lot?

Wee Ginger Dug: 'I felt connected to Scotland's beauty, even as I mourned the death of my beloved partner Andy'

Gordon MacIntyre-Kemp: The battle may have been lost but not the war

Sturgeon tells Cameron he’s ‘on borrowed time’ as she calls for PM to listen to Scotland’s voice

Project Fear: Story of how the Better Together campaign nearly fell apart

Jeanne Freeman: The indyref created a space to reinvigorate gender politics