The debate offered a prime opportunity to win favour with voters looking for stronger action to protect the Great barrier reef, better climate change targets and stronger laws to protect nature.
Unfortunately, what we got was a mostly unedifying display of tired party lines that failed to inspire confidence from either side.
Despite recent polling showing that climate change is one of the top four issues for voters at the upcoming election – debate showed that thus far both leaders are relegating serious action on the environment to the too hard basket.
Let's break Sunday's leaders debate down. The two candidates were asked seven questions by three selected journalists. Climate change only made its way into the debate on a few occasions including in response to a final question focused on the government's climate change policy.
We might have expected Bill Shorten to jump on the opportunity to talk up the massive potential to boost the Australian economy and create new clean energy jobs through renewable energy technologies, particularly given the fact that global investment in new clean energy reached a record high of US$329 billion in 2015.
We know Australians love renewable energy because Australia has the highest uptake of solar panels in the world.
Over 15 per cent of Australian homes now have solar panels on their roof.
Moreover, Labor's recently released climate policy represented an important step towards cleaning up Australia's energy sector including welcome measures to close dirty coal-fired power stations, build new clean energy, clamp down on land clearing and invest in renewable energy – but Mr Shorten seemed shy of selling these policies in the national debate.
With both major parties talking about innovation as a major part of growing our economy, how is it possible that clean technologies were not connected to that message?
Despite referring to himself in the debate as someone "who is committed to action on climate change", Mr Turnbull repeated the disingenuous lines we have been hearing from the Environment Minister, Greg Hunt, that his commitment is to ensure that Australia meets the targets agreed in Paris.
Yet the pollution reduction target Mr Turnbull was referring to – 26 to 28 per cent pollution reduction by 2030 based on 2005 levels - is hopelessly inadequate and completely out of sync with the Paris Agreement goal of limiting global warming to 2 degrees and to pursue a limit of 1.5 degrees.
In fact, simple analysis shows that if other developed countries had similarly low ambition we would be in line for a catastrophic 3 to 4 degrees of warming.
Later in the debate, Bill Shorten attacked Malcolm Turnbull for supporting the Direct Action Plan and Emissions Reduction Fund, which are policies inherited from Tony Abbott's days and which as a backbencher in 2009 Mr Turnbull famously described as "Bullshit."
What remains mystifying is that Malcolm Turnbull spent the debate repeating his 'jobs and growth' mantra like a broken record, yet failed to mention the massive opportunities inherent in the growth of renewable energy and related technologies for a truly agile future for this country.
Clean, renewable energy = jobs and growth!
Instead, Mr Turnbull took the defensive position of renewables - attacking the ALP for their more impressive 50 per cent renewable energy target by 2030.
Despite a recent series of statements from the Government about innovation as a driver for jobs and growth, these have been largely undermined by actions such as removing the Australian Renewable Energy Agency's (ARENA) remaining funding from the budget and removing their grant making function and abolishing climate jobs from the CSIRO.
Maybe this explains why Malcolm Turnbull did not talk about renewable energy as a driver for his often-repeated 'jobs and growth' agenda, because it would expose him to being caught out on the Government's record.
Bill Shorten had an opportunity to criticise the government on its record and to talk up the ALP's own more ambitious climate policies, but like much of the debate itself, it remains a missed opportunity.
This inaction on serious environmental policies is born out in ACF's election scorecard, released today, which was only able to give the Liberal/National coalition 11 per percentage points out of 100 (woefully low), while the ALP scored 53 and the Greens 77.
Clearly there is room for improvement all round.
Yet with a whole month to go between now and election day – we can only live in hope that both leaders take the opportunity now to improve their environmental policies and give voters something to really believe in.