The 7 charts that show climate change can be solved

Emerging over the last few years as a prominent voice in the climate movement, Hannah Ritchie is a data scientist who brings a no-nonsense approach to answering the big questions about climate change — and she does so with graphs.

A senior researcher at the University of Oxford and deputy editor at Our World in Data, Ritchie first gained prominence via her Substack, where she offers short commentaries accompanied by simple charts to explain why climate change is solvable, how much cheaper renewable energy is than fossil fuels, or why the green tech revolution is moving so quickly.

The Star sat down with her over Zoom to discuss her newest book, “Clearing The Air,” which debunks many of the myths and misconceptions around climate solutions and charts a realistic and achievable path toward a low-carbon world.

What follows is Ritchie’s explanation of seven charts from the book that together demonstrate why the transition to net zero is not only possible, but already happening.

They describe a pathway often referred to as “electrify everything,” which involves converting most of what currently runs on fossil fuels — heating, transportation and industry — to running on electricity, while also building non-emitting electricity — wind, solar and nuclear — to power it all. Progress along these two tracks of electrification and clean electricity is already faster than projected — providing a glimmer of hope in the otherwise bleak fight against climate change.

This interview has been edited for clarity and length, with seven accompanying charts from Ritchie’s book, published by the MIT Press.

The Star: Can we build renewables quickly enough?

Ritchie: The question often comes up — that there’s no way that we could possibly deploy clean energy as quickly as we need to. We tend to build energy projects relatively slowly. But what this chart shows is that if you plot the rollout of different energy technologies over time, you see that solar and wind are being built much more quickly than we built coal or gas in the past.

So this kind of thinking that we can’t go any faster, that is wrong. We can generally build these technologies much faster than we could in the past — and a big part of that is because they are relatively modular. It’s not like we are building some huge gas, coal or nuclear plant, which can have delays; it can take a long time to build large centralized projects. Renewables tend to be distributed modular solar parks or wind farms, and you tend to be able to build them at least twice as fast as fossil fuel projects. We can build solar and wind much more quickly than we were building all energy infrastructure in the past. 

Will renewables be able to power the world?

A very common argument against renewables is to show a big stacked bar chart of all the energy the world consumes today and say, “There’s absolutely no way you’re going to build enough clean power or clean electricity in order to replace that.” I do think that it’s a tall order.

The good news is that we don’t have to build as much as that. That’s because electricity is much more efficient than burning fossil fuels. If we electrify transport, lots of heating and parts of industry (and there’s still a little bit left that we can’t quite electrify, but that’s fine), the total amount of energy we need goes down by 40 per cent. So you’ve nearly halved the amount of energy that we would need just from that electrifying step. That’s a huge difference in the kind of forward-looking projections of how much energy the world will need. It needs far, far less energy in a decarbonized, electrified system than it does today in our very fossil-fuel-driven, non-electric system. 

Won’t data centres and AI eat up all the new electricity we produce? 

I should start by saying this is a projection, and the future of AI is very uncertain. But this chart is from the International Energy Agency, and it’s their projection of what will be driving growth in global electricity demand between now and 2030. Data centres are on there, but it’s far down the list, behind air conditioning, electric vehicles, buildings, industry and heating. 

Yes, it will be a driver of additional electricity demand, but there are lots of other things also driving electricity demand across the world. We should care about doing AI and data centres sustainably, but some of my concern is that we become so hyper-focused that we also forget about the other stuff that’s going on. If you were to ask people, they would assume 10 or 20 per cent of the world’s electricity is going into data centres. In reality, data centres use about 1 to 2 per cent, and most of that is not AI. They’re powering all of the digital services we use: banking, working on the internet all day, all of the digital stuff we use.

And yet, often I find now in climate discussions that all of our attention is on what to do about data centres. My concern is that it comes at the detriment of us focusing on the other 99 per cent. 

What about all the mining needed for renewables and batteries?

This is often an argument that’s brought up against renewables, because we do need mining. We need mining for different minerals and metals in order to get them to work.

But the key point is that the amount of mining we need for renewables is not zero, but it’s far, far less than for fossil fuels. If we were to build a low-carbon energy system over the coming decades, we would probably need hundreds of millions of tons of minerals. And that sounds like a lot — people say, “Well, of course, that can’t be sustainable,” — until you put it in perspective of how much stuff we currently dig out of the ground every year just to maintain a fossil fuel system.

We’re currently extracting about 15 billion tons of fossil fuels every single year. So in a single year, we’re probably doing the equivalent amount of mining that would be needed over decades to produce a low-carbon energy system. We’re talking about at least an order, if not several orders, of magnitude lower amounts of mining for low-carbon or renewable energy sources, versus fossil fuels.

Beyond that, it’s how the materials you mine are used. In the current fossil fuel-dominated system, you extract it, you burn it, and it’s gone. So you always need to extract more, and that will be our future if we maintain burning fossil fuels. With renewable energy technology, yes, you do need that initial mining and that initial digging, but then you have that technology for 30 years or more, continually producing electricity from the wind or the sun. And even at the end of that time, the material isn’t wasted because you can recycle it.

It actually gets more exciting than that because there has been huge innovation in building solar panels. If you were to take a solar panel that was manufactured 20 years ago and take the materials out of it, there’s probably enough to produce two solar panels, maybe four solar panels, or even eight, because the amount of silver or polysilicon that you need now is far less per solar panel. They’ve become much more efficient.

Renewables are very far away from this extract, burn, extract, burn, extract, burn economy. It’s a completely different system. 

What will happen to all the jobs in Canadian oil and gas? Won’t they all be offshored to Chinese manufacturing?

Let’s say you’re building a solar farm. You need the raw materials and the solar panels themselves. But that’s just the start of the supply chain. You need people to install the solar panels, and you need people to develop the project. You need people to do the maintenance. You need to be able to do repairs. There’s a whole chain of jobs that are needed. Most of those jobs cannot be offshored, right?

If you want to build a solar farm in Canada, the installer needs to be in Canada. You can’t have someone doing it from overseas. So a huge part of this overall clean energy supply chain is domestic, even if you’re not doing the manufacturing domestically.

Working out whether to do manufacturing at home or whether to import is a tricky geopolitical/national security kind of dilemma that many countries are in. You could take one of two approaches: China can produce solar panels extremely cheaply. It can produce them much more cheaply than Canada, the US or Europe. One approach is to say, we’ll take the cheap solar panels, and we’ll build solar as quickly as we can in Canada. You can buy more of them, and you can build that out more quickly. The plus is that because you’re building more stuff and going more quickly, you have more of the other jobs in the supply chain.

Then you have the other approach that says, we’re going to do manufacturing in Canada, we’re not going to import any panels. That’s good for manufacturing and will generate manufacturing jobs. The downside is that it will be more expensive, and therefore you’ll probably go slower on the build-out. So you’re sacrificing the jobs in installation and repair and all the other parts of the supply chain.

If you want to maximize the total number of jobs, which approach should you go for? The data on this would say that you should just import the cheaper solar panels and build quickly because the number of jobs in the supply chain outnumbers those in manufacturing. Again, these are some knotty issues. I’m not saying that no country, apart from China, should manufacture this stuff. But I think it’s important to recognize that the clean energy economy is much more than just manufacturing — there’s a whole host of other jobs. 

Wouldn’t switching to Chinese-manufactured renewables damage energy security?

Energy crises happen periodically. So we are in the current situation in Iran, but it wasn’t too long ago when it was Russia and Ukraine creating huge energy shocks. It happens so often that this is a very strong repeating pattern: Whenever there is a geopolitical conflict between countries that are large producers of fossil fuels, there are extreme ripple impacts for basically every country in the world. And that’s because 86 per cent of the world’s countries are net fossil fuel importers. For energy security, that’s just extremely bad. 

What you would get from shifting to a more renewable-based system is that you can gain a lot more energy security, and that’s because you do not rely on this constant stream of fuel. Once you’ve bought the product, the fuel is basically free. Once you put a solar panel on your roof, you have that energy coming at you for the next 30 years, regardless of what’s going on across the rest of the world. So by shifting to a more renewable-based system, the majority of countries in the world have more than enough domestic potential to basically power themselves. Around 92 per cent of the world’s countries can do this on a fraction of the land that they have. They would massively increase their domestic energy security and not be at the whims of whatever countries across the other side of the world are doing. They’d have that control.

Now, the argument that always comes up is that China produces huge amounts of these energy technologies, solar panels, batteries and EVs. Aren’t you just switching one dependency for another? What if they cut you off? Or what if the prices of solar panels dramatically increase for some reason? Again, the key point there is that once you’ve bought it, it’s yours. Tomorrow, if you want energy, you don’t need to buy a new solar panel.

While there is some dependency and risk, it’s more about the risk to the energy transition and the speed of the energy transition rather than energy security. If China tomorrow said, “We’re not producing any more solar panels. You can’t have any,” the energy transition would slow down because we wouldn’t be able to get new solar panels until we started producing them domestically. But the ones that we’d already bought would be producing exactly the same amount of energy as they did yesterday. That’s a very different kind of dependence problem from the energy security issues that most countries across the world are facing at the moment. 

Doesn’t nuclear take too long and cost too much to help solve climate change?

We seem to be incapable of building a nuclear plant on time and on a reasonable budget. Those two are linked because part of the reason the budget balloons so much is that the timeline expands so much.

But that’s just not true in all parts of the world. This chart breaks down the cost of building a new nuclear plant per megawatt across different countries. And it’s true that in the U.S., the U.K. and most countries in the West, the costs are high. But they’re far lower in places like South Korea or China, and to some extent, India.

There are obviously differences in regulation and labour costs, but I think a big part of this is because in these countries, they’re actually building them reasonably regularly. Once you start building nuclear plants, you build up a skilled workforce that knows how to develop and engineer them, and you can start to get a bit better at it. One of the benefits that South Korea or China has is that they are just building nuclear plants, and they tend to be building them in the five- to seven-year range. So, longer than it would take to build solar or wind, but not so extreme like 15 or 20 years that you would find in other parts of the world.

For many countries in the West, we did this decades ago. And when you look at the timelines and the budgets for those projects, they were pretty reasonable. France and Sweden built a lot of nuclear reactors extremely quickly. They transformed their energy systems within a decade. Now, part of the challenge is that most countries have spent many decades building no new reactors. All of that expertise and experience is gone, regulations have changed, and now we need to build nuclear plants again.

It’s kind of like starting from scratch. The reality is that for many countries, nuclear is expensive to build. But I don’t think it has to be that way.