On the subject of energy decarbonisation, there are moonfaced optimists who insistently claim that net-zero emissions can easily be achieved by 2050, and “realists” like Vaclav Smil and Mark Mills, who warn that a transition away from society’s dependence on hydrocarbons, in Mills’s words, “is not feasible in any meaningful time frame”.

Hannah Ritchie comes off as a centrist and realist with an obsession for diligently researching facts – and she is optimistic.

If you read only one book on climate change and the energy transition, read Ritchie’s recent book, _Clearing the Air: A Hopeful Guide to Solving Climate Change – in 50 Questions and Answers_. Ritchie is a data scientist and senior researcher at the University of Oxford, and deputy editor at Our World in Data. Her graphs and charts are highly respected and widely cited. For example, her chart on global primary energy production by source in the last 200 years has been referenced innumerable times. She does careful research to reach her conclusions and is regarded as a reliable source for facts and data.

Therefore, close attention should be paid to her optimistic take on the future of the energy transition. She is not, however, a moonfaced optimist, but a realist. She avoids, indeed explicitly shuns, the absolutist terminologies used by the most unrealistic optimists, which are intended to imply that “net zero” is just around the corner. She says, “when I say ‘clean energy’ throughout this book, I really mean ‘cleaner energy’ because no energy source is completely pollution- or impact-free.” She advises, “Stop obsessing over arbitrary targets [such as, for example, net zero by 2050] and focus on how 2you can help to reduce our carbon emissions as quickly as possible.” She says, “A completely fossil-free world is not going to happen overnight. Not even in the next 20 years. We should be upfront about that. It is a transition, not an on-off switch.”

Ritchie is frank about the benefits — and the continued need for — fossil fuels. “Fossil fuels,” she says, “have brought huge benefits to humans. I know this is a controversial thing to say in a book about climate change, but you and I are probably here because of them.”

And poor countries are going to need fossil fuels to develop. But the impact of that increasing use won’t be intolerable because their emissions are very small compared to those of the rest of the world. If the poorest countries’ carbon emissions increase substantially while the richer world is decarbonising, it will have very little negative impact on that decarbonisation. And in the longer run, as the technologies of low-carbon energy improve, poorer countries may be able to leapfrog to those better technologies.

I’ll admit I have been reluctant to embrace solar and wind to lead the energy transition. I am a wilderness-loving environmentalist in the tradition of John Muir, who advocated preservation of wilderness in the US, accompanying president Theodore Roosevelt on wilderness jaunts and driving the creation of national parks. When I saw photos of seemingly endless expanses of solar panels, I thought that I didn’t want to see so much land taken up that way.

What I didn’t reckon with was a comparison with the amount of land taken up by agriculture – about half of it with the feeding of animals and the decarbonisation-inefficient creation of biofuels. Ritchie says, “The US uses 2.5% of its land — an area the size of the UK — to produce bioethanol, which provides 10% of its motor petrol supply. If it used that land for solar farms instead the US could generate enough electricity to power itself two to three times over. Yes, you read that right.”

On nuclear power, unlike too many solar and wind advocates, she gets it right. She says, “If the world had fully embraced nuclear power and stuck with it, we’d be burning far fewer fossil fuels and have much less polluted air than we do now.” And, she says, “There is still time for a comeback, but it will need a dramatic shift in public and political support, and major reforms to make it possible to build nuclear plants cheaper and faster.”

It bears constant reiteration, as she says, that, “You never see the headline ‘Fossil fuels killed 11,000 people from air pollution’ yesterday, yet a single accident at a nuclear plant that killed no one would be one of the year’s most talked about events.”

Such is the illogic of the too often fact-challenged energy dialog.

Ricthie is forthright when a recommended energy transition technology is too costly. For example, she says that heat pumps, one of the technologies that is always recommended — not in the future, but now — as part of the “electrify everything” energy transition strategy, is too costly right now without subsidies.

Building solar, wind, and nuclear will require a lot of mined materials. Some people, such as Mills, claim it is utterly unrealistic to believe that we can get enough of the required minerals. But Ritchie says we have enough of most minerals and we keep finding more. “It’s not about whether there are enough minerals in the ground,” she says, “it’s whether we can get them out in time.” On this topic, I would love to see a debate between Mills and Ritchie. Both are highly credible, yet there appears to be disagreement on this.

On geoengineering, such as stratospheric aerosol injection, Ricthie states the issues, objections and rebuttals as clearly and succinctly as I have ever heard them stated. Arguing for putting some resources into researching geoengineering, she says, “A huge climate curve ball is unlikely, but the odds are not zero. Having a ‘break-the-glass’ emergency solution to reduce some of these impacts seems sensible. But to weigh up the pros and cons responsibly, we need to know what the potential impacts of geoengineering might be.”

One disappointment is that Ritchie doesn’t say much about geothermal energy. Recent developments suggest that there is a possibility that massive amounts of energy could be obtained from deep geothermal wells, providing energy storage as well. And it could be a way for geological and other kinds of expertise to migrate from fossil fuel mining activities to geothermal mining, thus possibly getting fossil fuel companies fully on board with the energy transition.

But in a way, her most important observation is near the end of the book. (Note for example that solar and wind energy have truly become cost-competitive with fossil fuels only in the last 10 years – prior to that, such claims were made only on the basis of a flawed levelised cost of energy comparison made by the financial firm Lazard Freres; further, just think of all the other changes in technology in the past 20 years):

“We accept that changes have happened in the past but are sceptical that tomorrow, next year or the next decade will be much different. When it comes to climate technologies, this couldn’t be further from the truth. Things are changing quickly.”

The views expressed in this article may or may not reflect those of Pearls and Irritations.