The Star Builders Read online

  Today, the world uses 620 exajoules of energy per year. Of those, the US uses around 95. The US Energy Information Administration estimates that the planet will need half as much energy again by 2050. Other estimates put it a touch lower. Even for everyone now on the planet to have the same energy consumption per person as in the EU or the US, we’d need to find another 370 or 1,650 exajoules respectively. That’s a lot of extra energy that we need to find—and it has to come from somewhere.9

  The Energy Crisis

  If you think that the energy crisis that worries star builders so much is being solved because campaign groups are pressuring and electorates are increasingly concerned, you’re horribly wrong. While there’s a lot of talk, and ambitions are high, the data tell a different story. Both the world’s total and per person energy consumption are increasing, partly for the very good reason that extra energy directly makes people’s lives better. Over the decade to 2018, global primary energy consumption grew by 1.4 percent a year.10

  Most of the world’s energy (80 percent) is still generated by fossil fuels: oil, gas, and coal. That’s not new—throughout modern history, we’ve relied almost exclusively on a single type of chemical reaction for energy. The recipe: take hydrocarbons—chains of carbon atoms with hydrogen atoms attached—and burn them in oxygen to create water, energy, and carbon dioxide.11

  There are good reasons why fossil fuels have achieved such dominance. It’s hard to imagine an energy source that is easier to use: you need only dig it out of the ground and set it on fire, no lasers or force fields required. In the past, the price was low relative to other energy sources. Fossil fuels are able to respond quickly to demand, in just a few seconds in some cases. They don’t stop operating because it’s overcast or there’s no wind. They generate the right amount of power for anything, whether you’re trimming grass with a mower or lighting a city. And even the fossil fuel power plants with the largest output barely take up any space—less than one square kilometer to power almost 3 million homes. A wind farm of equivalent power would take up substantially more land area than Washington, DC.12

  Unfortunately, the overwhelming consensus is that we can’t continue to rely on fossil fuels; eventually they’ll just run out. As neatly summarized by David J. C. MacKay in Sustainable Energy—Without the Hot Air, the world was lucky enough to start the Industrial Revolution with 2 billion years’ worth of accumulated energy reserves in the form of fossil fuels. But at current production, there are 50 years left of oil and gas, and 132 of coal. It’s likely that we’ll find more fossil fuels if we look hard enough, but it won’t change the basic fact that they’ll run out sooner or later.13

  Even if we were to find more fossil fuels, the security and environmental problems they pose are so serious that we need to wean ourselves off them anyway. They tend to be concentrated in a few geographical regions, lending power to those countries that, more or less by chance, have them. In 1973, a group of countries cut production and exports of oil so effectively that the price rose four times over. Energy security is itself a good reason to kick the fossil fuel habit.

  Burning fossil fuels is also a major source of air pollution. Air pollution is thought to be a contributing factor in the deaths of nearly twenty-nine thousand people a year in the UK and, according to World Health Organization estimates, 8.8 million people worldwide (more than smoking). Even when it’s not killing you, pollution from fossil fuels has pernicious effects: one study of American students found that those who moved from a school with low ambient pollution to another with higher pollution experienced significant decreases in test scores and increases in behavioral incidents and absences. In the world’s most polluted cities, for example in India and China, the negative effects are even worse.14

  On a global scale, it’s the carbon dioxide, or CO2, produced by burning fossil fuels that’s the biggest problem. Human-caused climate change is predominantly created by the greenhouse effect of CO2; the CO2 comes from energy generation. Levels of CO2 in the atmosphere have risen dramatically over the last few hundred years, increasing almost 50 percent since the Industrial Revolution. The Earth hasn’t seen levels of CO2 this high for at least eight hundred thousand years.15

  Dr. David Kingham, vice chairman of Tokamak Energy, told me that the deep de-carbonization of the planet was going to be a bigger, more important challenge than getting to space. There’s certainly more at stake.

  We don’t yet fully know the consequences of messing with the global climate system, but what we do know is very bad. The planet is a complex machine; each part interacts with every other part. The best models predict that human-caused climate change will create rapid changes in temperature, which will have a large and negative effect on life on Earth—human and otherwise. If we breach a 2 degree Celsius (approximately 3.6 degrees Fahrenheit) increase in average warming, a third of the planet will experience life-threatening heat waves every five years. Virtually all coral reefs will be wiped out. Crop yields will fall, and there will be extensive coastal and river flooding, huge climate-related loss of biodiversity, and an increase in extreme weather patterns. Many of these changes are irreversible, at least on human timescales. Getting it wrong on climate change could be catastrophic.16

  Scarily, the catastrophe is already happening. The global average temperature for 2019 was 1.1–1.3 degrees Celsius (approximately 2.2 degrees Fahrenheit) above the levels of 1850–1900, according to several independently curated data sources. The World Health Organization (WHO) estimates that climate change is contributing to the deaths of around 150,000 people worldwide per year already.17

  In 2018, the Intergovernmental Panel on Climate Change (IPCC) revealed just how little time we have left to act, injecting new urgency into the energy crisis. To avoid the worst effects, it was previously thought that the rise in temperature should be kept to, at most, 2 degrees Celsius. But as more data are gathered and more supercomputer simulations run, it seems that this just isn’t going to cut it. The IPCC now recommends that we should keep warming to under 1.5 degrees Celsius (approximately 2.7 degrees Fahrenheit). We’ve already breached 1 degree Celsius, so this leaves very little room, and time, to act. Newspapers reported this as, “We have just twelve years to limit devastating global warming.” Such a specific timeline invites skepticism; a complete CO2 emissions halt a day after the deadline would surely still be welcome. But the point stands that we need to effect a massive reduction in greenhouse gas emissions as quickly as possible if we wish to avoid the worst climate outcomes.18

  Perhaps you think that we’re making progress on clean energy. Partly, yes. However, the consumption of oil, coal, and gas actually increased between 2009 and 2019 (though coal use may now be falling for good). Perhaps you’ve heard that electricity generation is greener because it’s easier for renewables to displace fossil fuels for that purpose. But even in restricting the discussion just to electricity, we encounter bad news: the shares of both non-fossil fuels and coal in electricity generation in 2019 were broadly unchanged from their levels of twenty years earlier. In 2019, coal was still the single biggest source of energy for making electricity.19

  Figure 2.1 shows how fossil fuels absolutely dominate world energy production. Fusion’s cousin, nuclear fission, supplies around 4 percent. Biomass refers to biologically grown materials that can be burned for energy, including wood. Solar, wind, and other forms of renewables are barely large enough to feature except for a sizeable sliver attributable to hydroelectricity (6 percent). There is a lot of talk about solar and wind, but on the scale of the planet’s energy consumption, their contributions are so tiny that you can barely make them out. The sad truth is that our energy mix means global emissions of carbon dioxide are still growing: on average, by 1 percent a year over the last decade.20

  Figure 2.1: World energy consumption by generation type tells a tale of fossil fuel domination, while wind and solar are so small that you can barely see them. Biomass includes wood-burning and biofuel.21

  How Can
We Solve the Energy Crisis?

  What the world needs is solutions. Star builders think they have one, but they’re not the only ones.

  Some people are saying that we can become radically more efficient in our use of energy. It’s a nice idea, and we should certainly be doing it where we can. Improvements in technology have led to replacement of old style incandescent lightbulbs (which converted most of their energy into heat rather than light) by LED bulbs that are five times as energy efficient. And due to commercial pressures, jet planes became twice as fuel efficient per kilometer between 1968 and 2014.22

  Energy savings are great, but they’re extremely unlikely to offer escape from the mess. One underappreciated reason is that if products are cheaper or better, people tend to buy or use more of them. This rebound effect means that technological improvements that make products consume less energy per unit can actually increase the amount of absolute energy consumed. Due to technological innovations, the price of six hundred hours of light fell from £35,000 (approximately $47,000) in fourteenth-century Britain to £2.89 ($3.86) in 2006; people can now work during the dark hours of the night, but only by using more energy. And we’re using a lot more jet planes than we did in 1968.23

  Perhaps the most fatal flaw undermining the ever-increasing energy-efficiency strategy comes from the laws of physics: that is, most tasks take a minimum amount of energy to perform. To make a good cup of tea, it’s necessary to boil at least one cup of water. There’s a fixed and immutable energy cost to get a cup of water to 100 degrees Celsius (212 degrees Fahrenheit) that you can’t reduce with efficiency savings: you can’t beat physics.

  There’s evidence that carbon taxes would help reduce demand for the kind of energy the world needs to cut back on.24 Economists don’t usually agree on anything, but most are in favor of carbon taxes as a way to cut emissions and combat climate change.25 But any serious solution will need to address the supply of energy too. For instance, to fill the gap that will be left if fossil fuels are removed from the mix, the size of scale-up in clean energy we will need is terrifying. The IPCC say that no more than 40 percent of our energy should come from fossil fuels by 2050. To achieve the IPCC goal will mean deploying carbon-free energy sources at a rate that is unprecedented.26

  Star builders have been keen to tell me that massive adoption of renewable energy (solar power, wind power, tidal power, hydroelectricity, and so on) is part of the solution. Renewables have some fantastic advantages—the most obvious being that they will never run out. They also already produce net energy, unlike nuclear fusion. In recent years, the prices of some renewables have plummeted too. In particular, solar power just keeps getting cheaper.27

  But, the star builders say, renewables alone aren’t going to cut it. They can’t provide energy at the scale, growth rate, and level of consistency that is needed to power the entire planet. As Sibylle Günter at the Max Planck Institute told me, the scale required puts them in competition for space and resources that serve other human needs, like food. The scaling problem is partly attributable to another inescapable bit of physics: the energy that renewable facilities tap into is diffuse. It’s impossible to mine a rich “vein” of sunlight because it’s distributed over the surface of the Earth. Coal, by contrast, is a dense ball of stored sunlight. The same diffusion problem posed by sunlight applies to energy extracted from waves and the wind.

  With renewables, the small amount of energy obtained per amount of land area, and their not being at 100 percent capacity all of the time, means that huge plants are needed. For the UK, which has a similar land area to the state of Oregon, to rely on wind alone for electricity would mean covering up to 17 percent of the country with onshore turbines, or 2.7 percent for solar photovoltaics.I28 Offshore wind and tidal power also require impractically large areas, and hydro and geothermal power aren’t available in enough places.29 Not everyone wants to live next door to a large-scale renewable plant either.30

  The renewable with the most promise, the one that could be scaled up the most significantly, is solar (though in some places, like Northern Europe, wind power will be more effective). Based on what has been learned from operating solar farms in the US, it would take two thousand solar power plants each the size of London to get close to providing current world energy consumption. It isn’t impossible, but it’s daunting and implausible. The UK government Committee on Climate Change thinks only about 60 percent of the country’s electricity will come from renewables by 2050, and few believe that even solar power will be able to supply more than 50 percent of electricity worldwide.31 Remember too that electricity is just one part of total energy use, and its share will need to increase substantially to beat climate change.

  In a sad irony, climate change itself makes the haul of energy from renewables less certain. As the worldwide pattern of both weather and climate changes, it will create renewable energy winners and losers. The potential for solar power will likely rise in Europe and China but fall in the western USA, Saudi Arabia, and across Africa. Overall, the effects seem likely to be negative: solar cell efficiency drops by about 0.5 percent for every one-degree increase in temperature, and weather effects mean a reduction of direct sunlight by 5 percent.32 Even if these shifting patterns create a redistribution of potential renewable energy rather than a reduction, the change presents a problem for policymakers.

  Another problem is that renewables, including solar, are inconsistent. On a still day, wind turbines produce next to nothing. Even if solar panels were pasted across most of the landscape, they’d still be vulnerable to the weather. Solutions could include building cross-continental power transmitters or smoothing out the uneven supply of electricity using enormous batteries. Unfortunately, those big batteries don’t yet exist. Tokamak Energy CEO Jonathan Carling is skeptical that batteries will ever do the job. “You can have a battery that extends the day a bit,” he told me, “but to have a battery that turns winter into summer is too much to ask.”

  Dealing with intermittency is also expensive, especially when renewables get near to providing 100 percent of the electricity supply. If power is scarce, you need instant, on-demand power, either from batteries or from a neighboring state. When power is plentiful, there is a risk of over-generation—of power flooding the grid and causing physical damage. Faced with that imminent prospect, a nation or state might have to pay its neighbors to take power.33

  Most studies put the plausible fraction of renewables’ share of total global energy at 27 percent by 2050. Renewables are going to be a key part of the solution to the energy crisis, a very large part, but not the whole story. They’re an absolutely necessary part of the solution, but they’ll likely be insufficient.34

  Of every star builder I’ve spoken to about whether a combination of existing technologies will be enough, First Light Fusion CEO Nick Hawker seems to have thought the most deeply about it, even commissioning a study by a third party.

  “We looked at the future of energy in the 2030s and ’40s,” he told me. “It’s instructive to ask what’s not the problem. It’s not cost. Solar and wind are already the cheapest form of energy generation. Full stop. And it’s not about energy intermittency either. We can debate about how you’re going to manage the last 10 percent of intermittency, but frankly if we’re in that world we’re doing pretty well.”

  So what is the problem in his view?

  “It’s the deployment and the maximum rate of deployment. The problem is scale, which is very bad news for climate change because none of the other options are very good, none of the other options are really proven—the only other one is nuclear fission.”

  Fission, now, that’s an idea.

  Nuclear fission already works. It produces next to no CO2 compared to fossil fuels, and even less than solar cells do.35 It’s not affected by the weather or climate, and it doesn’t require vast tracts of land. Powering the entire planet on fission would merely require fifteen thousand (1240-megawatt) fission plants. That’s a lot of nuclear power statio
ns, but they’d take up a tiny fraction of the land area that solar power would need.

  I should declare now that I’m a fan of fission power, and not just because it involves nuclear physics—countries that heavily rely on it are managing to get off fossil fuels. France and Sweden have gone further than most in de-carbonizing their electricity generation, with 75 percent and 40 percent, respectively, of their energy supplied by fission. France also exports a lot of that sweet, clean electricity to other nations.

  But I’m in the minority: an IPSOS poll, conducted after the tragic meltdown at the Fukushima nuclear plant, found that fission had the lowest public support globally of any source of power, including solar, wind, hydro, gas, and coal. Some countries are phasing out fission power altogether. “Fission faces a great acceptance problem,” Sibylle Günter said.36

  Nuclear fission certainly does have problems: radioactive waste, the possibility of dangerous events like reactor meltdowns, a finite supply of fuel, and the potential for the proliferation of nuclear weapons. I’ll dig into nuclear risks of all shapes and sizes more in Chapter 8. Fission can also be expensive, although it doesn’t have to be and the price varies widely depending on the context. The proposed fission reactor at Hinkley Point in the UK has a guaranteed price of £330 ($440) per gigajoule compared to £143 ($190) per gigajoule for the UK’s latest offshore wind sites.37

  Nick Hawker doesn’t think there’s anything inherent about fission that makes it expensive; after all, France’s role as a major exporter of largely nuclear electricity suggests they’re able to make it cheaply. He thinks it’s the very tight regulations around fission that are to blame. “We’re doing a pretty good job of showing we can’t make it economical, and regulatory considerations suggest we simply can’t do it,” he says. “China can build nuclear fission, and South Korea can, but we can’t.”