Saving our skins might be surprisingly cheap. To avoid dangerous climate change, the world needs to boost spending on green energy by $1 trillion a year. That sounds scarily large, but we could cover a lot of it using the subsidies currently handed to fossil fuels.
Governments have agreed to limit global warming to 2°C, because more than that may be impossible to adapt to. "We need to drastically transform our energy system," says David McCollum of the International Institute for Applied Systems Analysis in Laxenburg, Austria. "It is high time we thought about how much capital is needed."
McCollum’s team plugged that gap by analysing six different models that combine data on greenhouse gas emissions, energy scenarios and investment costs. The numbers work like this. Investment in low-carbon energy is currently $200 billion a year. But that isn’t enough. For a 70 per cent chance of keeping below 2°C, the investment will have to rise to $1.2 trillion a year.
Spending is set to rise as energy demand increases and governments meet their existing climate commitments. The world is probably already committed to doubling green energy investment to $400 billion a year by 2050, says McCollum. But even with that, we still need to find another $800 billion a year.
That sounds like a lot to make up. But global investment in energy is already $1 trillion a year and rising, says McCollum. The problem is that much of that investment goes to fossil fuels. According to the International Energy Agency, government subsidies for fossil fuels are around $500 billion a year, six times more than subsidies for renewables.
"The magnitude of the clean-energy investment challenge is roughly similar to today’s fossil-fuel subsidies," says McCollum. So if we used the subsidies for coal, oil and natural gas to invest in solar, wind and nuclear energy, global warming would be close to being solved.