Too late for renewables: By 2050 half the world’s population will be living in megacities like Tokyo (pictured), powered mainly by fossil fuels (photo: Morio CC BY-SA 3.0)

During a period as a scientific adviser in Whitehall, I quickly learned the elements of sound advice given to politicians — a process that is quite distinct from lobbying. A well-briefed minister knows about the general area in which a decision is sought, and is given four scenarios before any recommendation. Those scenarios are the upsides and the downsides both of doing nothing and of doing something. Those who give only the upside of doing something and the downside of doing nothing are in fact lobbying.

This flaw is well exemplified by Nicholas Stern in his latest book Why Are We Waiting? The Logic, Urgency, and Promise of Tackling Climate Change (MIT Press, 376pp, £19.95), which is based on lectures given in 2012 at the London School of Economics. In his introduction he makes it clear that he has consulted many scientists, businessmen, philosophers and economists, but in his book I find not a single infrastructure project engineer asked about the engineering reality of any of his propositions, nor a historian of technology about the elementary fact that technological breakthroughs are not pre-programmable. Lord Stern’s description of the climate science is an uncritical acceptance of the worst case put by the International Panel on Climate Change (IPCC), one from which many in the climate science community are now distancing themselves. There is no other complex, multi-component, closely coupled, highly non-linear and chaotic system for which we make any forward predictions, let alone those of 35 years ahead, and the poor record to date is no surprise. The absence of the promised temperature rises over nearly 20 years now is blunting the credibility of their longer-term predictions in the eyes of the public, as many polls show. The response to all this is not more science — it is engineering and technological reality, as well as economics and ethics.

Indeed, it is worse than that. Those of us who doubt this catastrophic scenario are not sceptics of climate change, as history and geology give the clearest evidence that the climate has changed continuously. But Stern accuses us of being selective in examining the data, when he is guilty of just the same. For example, the IPCC report on extreme weather, on which he relies, chooses to start its data baseline in 1960, conveniently overlooking the wealth of empirical data showing that extremes of almost all forms of weather were much worse in the first half of the 20th century than the second, before the onset of man-made climate change.

Nor does Stern look at the data that is in on the physics of renewable energy sources, which shows that they will never be more than a bit player (of the order of 10-20 per cent) in providing the world’s energy. David MacKay, author of Sustainable Energy — Without the Hot Air (UIT, 2008), makes this abundantly clear for the UK; where the data is in for Germany and Spain, a dispassionate analysis undermines much of Stern’s tendency to see renewables through rose-tinted glasses. There is no counter-example to the fact that government subsidies for the premature roll-out of these new technologies have been a disaster. In the past, hard times have resulted in a roll-back of these subsidies, as in Spain, Portugal and Greece. Spain, for example, is indebted by €100 billion because of energy subsidy commitments, a sum three times greater than the €36 billion bail-out of its banks a few years ago. Now the UK, Germany and others are rolling subsidies back because they threaten both social cohesion (through the rising cost of energy for the poor) and industrial stability. The Green Deal and other subsidies for which Stern pleads are already being dismantled. Technology historians will show that energy and other major infrastructure projects develop on a 40-year timescale. Even if there was a technical breakthrough today to tame nuclear fusion — and we have been seeking one for 60 years now — it would be 2050 before 10 per cent of the world’s energy supply came from that source.

In Germany €200 billion has been invested in renewables, yet wind and solar energy each produce about 8 per cent of electricity per annum. For large parts of winter they produce little or nothing, and so there is no relief for the fossil fuel and nuclear plants (if the latter are given a reprieve) to produce the peak annual demand. The combined cycle gas turbines, with shafts designed to turn on and stay on, providing base-load electricity, are uneconomic when run in load-balancing mode: not only do they produce less and so have to charge higher prices, but more worryingly, the constant acceleration and deceleration shortens the lifetime of the shafts. Some turbines are being turned off until they are needed for baseload applications sometime in the future.

The starkest fact, hidden in Stern’s chapter on ethics, is the plight of the world’s poor. One of the most positive aspects of the last 20 years has been the doubling from 1.5 billion to 3 billion of the number of people in the world living in what the World Bank calls “the middle class”: those who have electricity and running water in the dwelling they call home. BP data shows that this has coincided with a 40 per cent increase in global energy demand, 88 per cent of which has been provided by fossil fuels, and less than 1 per cent by renewables. The World Bank predicts that by 2035 the middle class will grow from 3 billion to 5 billion out of a total population of 8 billion. BP estimates that the world demand for energy will increase by another 40 per cent in total; more than 80 per cent of that will again be provided by fossil fuels.

It would be immoral to stop that process. Even if the developed world was to halve its CO2 emissions over the next 20 years, the overall global emissions will grow as China, India and Africa continue their rise out of grinding poverty into a middle class existence. By 2050 more than half the world’s population will live in megacities, where local renewable energy will only serve people living on the top floor of high-rise buildings, and where nearby land is already dedicated to food production. Only fossil fuels and nuclear energy will power megacities in 2050, and it is too late now to expect anything substantially different. Over the last decade, as 600 million people left the Chinese countryside for high-rise cities, the growth in primary energy sources was more than 140 million tonnes of oil equivalent (toe) per annum while the best of the renewables was in the last year which saw a growth of only 10 million toe. This will continue for at least another decade in China, while India and Africa will start a phase of urbanisation that will last at least 20 years.

On the upside of CO2 emissions, ministers should bear in mind just one fact and one prospect for the future. The world’s biosphere has greened considerably — by more than 10 per cent over the last 30 years — because of the extra CO2. This figure takes into account the contrary impact of deforestation and land-use change and much of it has taken place where it is needed, such as in the Sahel. While the climate science community has been focusing on one source of global warming, it has been largely silent on the behaviour of the sun, and dismissive of those who point out that the pattern of sunspots is now mirroring that last observed at the outset of the Little Ice Age from about 1300 to 1850. The most recent work of the solar physics community has been reinforcing this message. As I pointed out in The Times in 2010: “One possible scenario for 2050, no less possible than any projected on the basis of climate models, is that we are in the middle of a deep solar minimum, and it is only the CO2 pumped into the atmosphere over the previous 100 years that is staving off cold climates that would lead to crop failure and mass starvation. The uncertainty is not only in the science and in the scenarios, but in what is a reasonable response today.” Remember there will be about nine times as many people on the planet in 2050 as there were during the Little Ice Age.

If the engineers can show that a Western-style livelihood is possible with half the CO2 emissions per person per day, then where is the sociology of persuasion to change lifestyles because profligate consumption is widely deemed to be antisocial? If we were to drive less, fly less, source food and goods from more local sources, we could have a real impact on CO2 emissions. Instead, all we have is misplaced technological optimism. There is no free lunch, however, as the implied reduction in transport and economic activity would produce its own downsides. I was relieved that the Pope in his recent encyclical focused on profligacy and waste and urged the development of the poor ahead of halting climate change if the two should conflict.

Those building the biblical Tower of Babel, intending to reach heaven, did not know where heaven was and hence when the project would be finished, or at what cost. Those setting out to solve the climate change problem now are in the same position. If we were to spend 10 or even 100 trillion dollars mitigating carbon dioxide emissions, what would happen to the climate? If we can’t evaluate whether reversing climate change would be value for money, why should we bother, when we can clearly identify many and better investments for such huge resources? The forthcoming Paris meeting on climate change will be setting out to build a modern Tower of Babel.

Lord Stern answers his own question — why are we waiting? — most eloquently in chapter five, “The Ethics of Intertemporal Values and Valuation”, which is a positively theological discussion with other economists asking by how much we should discount future values. If the response now to the perceived challenge of climate change has any relation to discount rates, we should wait until this debate is settled. The empirical data shows that investments in first-generation renewables are wasted if the justification is solving the climate change problem, as only 1 per cent of global energy comes from these since R&D started in the 1970s after the first oil shocks, and we are over halfway to 2050 when they are supposed to have reduced our carbon emissions by 80 per cent from 1990 values.

Past pessimists such as Thomas Malthus, William Stanley Jevons and Paul Ehrlich have been proven comprehensively wrong in their predictions of gloom, and I am confident that Nicolas Stern will join them. As Patrick Allitt observed in A Climate Of Crisis: America In The Age Of Environmentalism (Penguin, 2014): “Few people have paused to ask: How would we benefit now if our grandparents and great-grandparents had exercised more self-restraint and self-denial? Would we live better if they had exercised greater prudence and self-control?” The wise response now and for the foreseeable future is to continue to develop the world using mainly fossil fuels, to pursue R&D towards alternative low-cost energy sources, and to adapt as and when future changes in climate actually emerge.