What is the appropriate response to the threat of climate change? To some climate activists, it means we must give up on economic growth, capitalism or even industrial society itself. This extreme viewpoint, if correct, would require modern humanity to abandon much of what makes life comfortable and secure. It also causes many on the political right — and some in the centre — to suspect climate activism of being merely an excuse to end capitalism. That suspicion makes the lure of irrational climate change denial all the more seductive.
Fortunately, a large number of people accept the reality and the danger of climate change, while believing that humanity can escape most of the threat without the need for dramatic decreases in quality of life. This will require a combination of innovation and regulation — technologies to make prosperity less dependent on carbon, and policies, such as carbon taxes, to discourage releasing greenhouse gases in the atmosphere.
Already great strides have been made on the technology front. Solar power has become much cheaper: batteries, which enable solar power to be stored at night and on cloudy days, have also advanced greatly. Partly as a result of these developments, Bloomberg New Energy Finance forecasts renewable energy to dominate electricity generation in the world’s biggest economies by 2050.
This is all great news. It also probably increases the scope for carbon taxes; as better alternatives become available, curbing fossil fuels will mean less of a hit on growth, and will be more about simply nudging businesses to pay the costs of switching over.
It will be decades before renewable energy reduces carbon emissions to low levels, even with a boost from carbon taxes. During that time, much more carbon will be belched into the air
Renewables not enough
However, as wonderful as renewable energy is, it probably won’t be enough to avert severe climate change, for several reasons. First, it will be decades before renewable energy reduces carbon emissions to low levels, even with a boost from carbon taxes. During that time, much more carbon will be belched into the air, which will stay up there for many years.
Second, cheap renewables also make humanity richer, causing people to consume more energy — a phenomenon known as the income effect. This might work against cutting carbon pollution, because it could mean burning more fossil fuels in the places where they’re still in use. Third, renewable energy won’t readily replace fossil fuels in some applications, such as aviation, meaning the economy will probably never eliminate all carbon output.
For all these reasons, even if renewables allow governments to keep their current pledges, it will still probably lead to large increases in the Earth’s temperature.
More is needed. One option would be to shrink worldwide economic activity by a huge amount. Another would be to invest heavily in renewables right now, before they become cheap — a very costly switch. Either of these options would result in a big hit to human standards of living — especially in developing countries like India, where many people would lack basic sanitation, or even starve, if they became much poorer than they are now.
The inventors of the new technique estimate that if costs continue to fall as they expect, they could capture all the carbon the world emits for only 5% of global economic output
But a third option may have just become feasible. For a long time, people have dreamed about technology that would allow carbon to be pulled out of the air and stored in the ground or recycled into fuel. Now, a team of Harvard scientists is claiming they have a much cheaper way to do this.
The scientists, led by David Keith — who has also formed a company called Carbon Engineering to commercialise his invention — have been testing technology at a pilot facility in Canada for years. Their claim — which some other experts find believable — is that they can remove carbon dioxide from the atmosphere much more cheaply than previous approaches, with greater cost reductions still to come.
Direct air capture is a crucial piece of the puzzle in lowering carbon levels. There’s really no other way to get rid of the carbon that’s already in the atmosphere, other than waiting the decades or centuries it takes to go away on its own. This technology will help humanity go beyond simply avoiding further damage to the planet’s environment, and fix some of the damage we have already caused.
Also, direct air capture is a way to do deep decarbonisation without waiting for renewables to become dirt-cheap. On the margin, emissions reduction — through energy efficiency, reforestation and renewable energy — is still cheaper than pulling carbon out of the air. But deep decarbonisation — reducing emissions not by a small percent, but by large amounts — would still be extremely expensive, which is why no one is doing it yet.
However, unlike emissions reduction, direct air capture’s economic costs probably don’t balloon — building 100 carbon-capture facilities should be more or less 100 times as expensive as building one. The inventors of the new technique estimate that if costs continue to fall as they expect, they could capture all the carbon the world emits for only 5% of global economic output.
Those predictions are probably overly rosy. And 5% of global output is still trillions of dollars. A much more realistic scenario is for nations to use carbon removal as a supplement to renewable energy and energy efficiency. Even spending 1% of global GDP would require a huge commitment by many industrial nations; and developed countries would probably be asked to foot more of the bill, having already emitted a lot of carbon in the past. There will be many political sticking points.
But carbon capture is now at least moving out of the realm of science fiction and into the realm of the possible. Stopping climate change will still require a large, global, co-ordinated effort, combining carbon taxes (or similar policies, such as cap-and-trade), continued advances in renewable energy, and government-funded carbon capture. But thanks to the magic of human innovation, we will be able to save the planet while also preserving our modern industrial society and keeping the engine of economic growth humming.