If the scriptwriters of the film Apollo 13 got a dollar every time somebody quoted their dialogue, they could probably fund the next space mission themselves: "Houston, we have a problem"; "Failure is not an option". But my favourite line hardly ever gets an airing.
It comes from the key scene in which the astronauts and mission controllers struggle to find the tiny amount of power - just four amps - required to restart the command module's systems and bring the crippled spacecraft safely home.
"Ken - you're telling me what you need. I'm telling you what we have to work with."
For me, the scene provides a perfect analogy for the challenge of achieving sustainable development we face today. In both, the mission is life-or-death important and resources are critically constrained. The astronauts and engineers work together to solve the problem by fundamentally rethinking their energy systems, and we must do the same.
By 2030, the UN's Sustainable Development Goals commit us to abolish poverty and hunger; provide good healthcare, education, decent work, gender equality and access to clean water for all; and to promote affordable clean energy, sustainable cities, infrastructure, climate action, economic growth and responsible consumption.
The problem is that western standards of living have been achieved through reckless resource depletion, pollution and greenhouse gas emissions. If everyone on earth took the same route, we would quickly need the resources of three planets, and even if we could conjure up those resources, climate change would soon snuff us out.
We cannot deny the legitimate aspirations of billions. Our aim has to be a world where everyone can live well and within the sustainable limits of our planet. Increasing demand is a given, resources are finite and time is against us. This is our Apollo 13 moment.
That means going back to first principles. Instead of asking how to improve the efficiency of incumbent technologies by a few percentage points, we need to start from the other end of the problem, and ask what services we need, and how we can redesign the system to meet them within our available natural resources.
This is nowhere truer than in cooling - the invisible pillar of civilisation. Without cold, the supply of food, medicine and data would simply break down. But conventional technologies are also energy intensive and highly polluting and cooling demand is growing at a furious pace, driven by population growth, rising incomes and changing lifestyles in developing countries. On current trends, by 2100 the electricity needed for global air-conditioning alone will equate to around half the power generated for all purposes today.
We cannot simply green this volume of new electricity. To reconcile this demand with finite resources, we need transformational thinking. We need to bring together the key stakeholders to deliver a system-level approach that fundamentally rethinks our delivery of cooling.
Currently when we talk about energy, we often mean electricity, and when we talk about energy storage, we default to batteries. This blurring of concepts matters because it fails to recognise that much of our energy is already consumed as heat or cold; that cooling will be one of the fastest growing sources of energy demand for the rest of this century and that cooling would often be better served by energy carriers other than electricity and batteries. So like the astronauts, we urgently need to rethink our energy systems. And, like the Apollo 13 team saving the lives of three astronauts, clean cold will help bring the world's consumption of primary resources safely back down to earth.