In the run up to the Copenhagen conference, a UK broadcaster has been soliciting opinions from scientists in response to the question “Which idea, policy or technology do you think holds the greatest promise or could deliver the greatest benefit for addressing climate change?”. Here’s the answer given by myself and my colleague Tony Ryan.”
We think the single most important idea about climate change is the optimistic one, that, given global will and a lot of effort to develop the truly sustainable technologies we need, we could emerge from some difficult years to a much more positive future, in which a stable global population lives prosperously and sustainably, supported by the ample energy resources of the sun.
We know this is possible in principle, because the total energy arriving on the planet every day from the sun far exceeds any projection of what energy we might need, even if the earth’s whole population enjoys the standard of living that we in the developed world take for granted.
Our problem is that, since the industrial revolution, we have become dependent on energy in a highly concentrated form, from burning fossil fuels. It’s this that has led, not just to our prosperity in the developed world, but to our very ability to feed the world at its current population levels. Before the industrial revolution, the limits on the population were set by the sun and by the productivity of the land; fossil fuels broke that connection (initially through mechanisation and distribution which led to a small increase in population, but in the last century by allowing us to greatly increase agricultural yields using nitrogen fertilizers made by the highly energy intensive Haber-Bosch process). Now we see that the last three hundred years have been a historical anomaly, powered by fossil fuels in a way that can’t continue. But we can’t go back to pre-industrial ways without mass starvation and a global disaster
So the new technologies we need are those that will allow us to collect, concentrate, store and distribute energy derived from the sun with greater efficiency, and on a much bigger scale, than we have at the moment. These will include new types of solar cells that can be made in very much bigger areas – in hectares and square kilometers, rather than the square meters we have now. We’ll need improvements in crops and agricultural technologies allowing us to grow more food and perhaps to use alternative algal crops in marginal environments for sustainable biofuels, without the need to bring a great deal of extra land into cultivation. And we’ll need new ways of moving energy around and storing it. Working technologies for renewable energies exist now; what’s important to understand is the problem of scale – they simply cannot be deployed on a big enough scale in a short enough time to fill our needs, and the needs of large and fast developing countries like India and China, for plentiful energy in a concentrated form. That’s why new science and new technology is urgently needed to develop these technologies.
This development will take time – with will and urgency, perhaps by 2030 we might see significant progress to a world powered by renewable, sustainable energy. In the meantime, the climate crisis becomes urgent. That’s why we need interim technologies, that already exist in prototype, that will allow us to cross the bridge to the new sunshine powered world. These technologies need development if they aren’t themselves going to store up problems for the future – we need to make carbon capture and storage affordable, and to implement a new generation of nuclear power plants that maximise reliability and minimise waste, and we need to learn how to use the energy we have more efficiently.
The situation we are in is urgent, but not hopeless; there is a positive goal worth striving for. But it will need more than modest lifestyle changes and policy shifts to get there; we need new science and new technology, developed not in the spirit of a naive attempt to implement a “technological fix”, but accompanied by a deep understanding of the world’s social and economic realities.