To limit global warming to 1.5˚C by the end of the century, the world has to deploy clean technologies en masse while slashing investment in new oil, gas, and coal supplies, according to a new report by the International Energy Agency.
Getting to net-zero carbon emissions by 2050 will require a historic deployment of widespread renewable power, electric vehicles, and new technologies, many of which are only now in the prototype stage. To get a jump-start, we’ll need to double our investments in clean technologies to $4 trillion by the end of the decade.
“The pathway to net zero by 2050 is narrow but still achievable if governments act now,” IEA Executive Director Fatih Birol said in a tweet. Most of the reductions in CO2 emissions through 2030 will come from technologies already on the market. But in 2050, almost half will come from technologies that are still in development.
“Big leaps in innovation are needed by 2030 to get these technologies ready in time,” Birol added.
The report comes as we’re unlikely to hit net zero by 2050. Currently, if countries stick to the voluntary contributions they’ve put forth to honor the Paris Agreement, we’re heading for more than 2˚C warming by 2100, the IEA says.
Bending the curve down to 1.5˚C will require overhauling just about every sector of the economy, hence the $4 trillion annual investment. It’s a significant sum, but it will also lift annual global GDP growth by 0.4 percent. Today, that number would add about $3.5 trillion in wealth worldwide.
Energy impacts
If global leaders started following the report’s recommendations tomorrow, the most significant—and immediate—impact would be the cessation of all new fossil fuel projects starting next year. Countries could continue extracting the oil, gas, and coal they’re currently exploiting, but they shouldn’t authorize any new exploration, drilling, or mining. Already, one oil company, Royal Dutch Shell, has said it won’t be exploring or drilling for new oil or gas beginning in 2025, though that’s still three years later than the IEA recommends.
“I don’t think anyone expected this from the IEA. It is a huge turnaround on their part,” Dave Jones, an analyst at climate think tank Ember, told the Financial Times. “It has been very pro-fossil, so to come out with something like this is just amazing… This is truly a knife in the fossil fuel industry.”
The rapid ramp-down of overall fossil fuel use—from 80 percent of the energy mix today to 20 percent in 2050—would necessitate a phase-out across the entire economy.
The IEA says that oil and gas demand should decline by 75 percent and 55 percent, respectively, and unabated coal demand needs to decline by 90 percent. Any coal plants still in operation by 2040 should be hooked up to carbon capture and sequestration (CCS) systems. By 2050, almost 70 percent of electricity should come from wind and solar power, with nuclear picking up much of the remainder. (The modest 15 percent growth of nuclear, the IEA expects, would likely come from new plants in China). Getting to a majority renewable grid will require a fourfold increase in annual installations of wind and solar generating capacity by the end of the decade.
We’ll have to get more efficient, too. Over the next 30 years, as the world adds 2 billion people, overall demand should decline by 8 percent, which would require significant increases in energy efficiency across the economy.
Changes to transportation
With transportation contributing about 20 percent of emissions today, the way we move will have to be rapidly decarbonized, too. Sales of electric cars—already up in the wake of the pandemic and looming regulations—will have to grow eighteen-fold by 2030. That would increase EVs’ market share from around 5 percent today to 60 percent in a decade, with nearly all light vehicles powered by batteries by 2050. The remaining 10 percent or so would be mostly fuel cell vehicles with very few plug-in hybrids.
Trucking would be similarly electrified, though with more hydrogen. Around 65 percent would be battery-electric, and the other 35 percent that cover distances greater than 400 miles in a day would be powered by fuel cells. For maritime shipping, the IEA doesn’t anticipate the sector to reach net zero. Instead, it expects hydrogen and ammonia to capture 60 percent of the market. Rail, the other primary shipping mode, is almost an afterthought because it is so straightforward to electrify.
Then there’s air travel. “Emissions are hard to abate because aviation requires fuel with a high energy density,” the report says. As a result, aviation gets a bit of a pass, contributing 10 percent of all unabated emissions in 2050 in the pathway. But to get there, the industry will still have to invest in what the IEA calls “sustainable aviation fuel,” which includes mostly biofuels with some help from synthetic fuels derived from CO2. To hit the targets, some air travel will have to disappear, primarily through replacing some short-haul flights with train trips and eliminating some business flights in favor of remote meetings (something we’ve all gotten accustomed to).
Housing and industry
Our homes and industry will have to change, too, though the IEA sees different pathways for each. For homes, heating and cooling can easily be switched to efficient, widely available heat pumps, which work at a surprisingly wide range of temperatures. Leaky buildings will have to be retrofitted with better insulation and air sealing, making them more comfortable to live in. Gas water heaters can be swapped for solar or heat pump models.
Natural gas will largely disappear from home use, with a small sliver of homes heated by hydrogen. Commercial buildings would largely follow the same trends. About 2–2.5 percent of all buildings worldwide will have to be retrofitted every year to hit the targets. Today, about 1 percent are.
Industrial uses of energy, including steel, cement, and chemical production, will have to switch to hydrogen or rely on CCS. The IEA says that about 40 percent of the reductions in industrial emissions by 2030 can happen through recycling, waste reduction, and more intelligent use of materials in building construction and design.
New technologies
The IEA’s models after 2030 rely heavily on technologies currently in the prototype phase to keep warming to 1.5˚C. In fact, almost half the emissions reductions by 2050 are forecast to come from clean tech that is currently at the demonstration or prototype phase. Most of those innovations will have to address heavy industry or long-distance transportation.
Both sectors have lagged because finding clean tech that can replace energy-dense fossil fuels is difficult. Shipping and aviation will be the most challenging, which the IEA acknowledges, reserving a significant percentage of unabated emissions for both.
Most industrial facilities can make the switch, though—typically, what’s needed is a heat source that is sufficiently concentrated and hot enough, not one that’s light enough to move around. A straightforward solution is to use electricity, but getting the necessary heat would involve adding considerably more renewable generating capacity. Another option is to swap higher-carbon materials, like steel, for lower-carbon alternatives, like compressed cellulose.
For industrial uses that we can’t easily electrify or replace, hydrogen has emerged as a leading candidate. The gas can always be burned, like a fossil fuel. It can also be used in clever ways to rethink how we make cement, which produces about 8 percent of emissions today. There’s also another source of hydrogen power—the Sun. The startup Heliogen has demonstrated that concentrated solar power can produce temperatures as high as 1,000˚C, which would be useful for the production of things like steel and cement.
Put it in the ground
Some emissions are difficult to avoid, of course. Many net-zero forecasts address the problem of unavoidable emissions by relying on carbon offsets, a process that attempts to quantify how much carbon is sequestered when forests are preserved, for example. Offsets are controversial, though, because companies can easily game today’s schemes, and it’s hard to guarantee that the offsets will remain valid in the distant future (a forest might burn, for example).
The IEA doesn’t rely on offsets for its roadmap, though. Instead, it turns to direct air capture and bioenergy with carbon capture and sequestration (BECCS). Both approaches suck CO2 out of the atmosphere and concentrate it for use or storage, but they go about it in different ways. Direct air capture modifies existing CCS technology to draw CO2 directly from the air (hence the name), while BECCS relies on chlorophyll. With BECCS, agricultural waste and fast-growing plants are collected and burned, with the resulting CO2 isolated for use or storage.
What it all means
The IEA is regarded as a relatively conservative agency. It’s a group that has consistently underestimated the growth of wind and solar power, in part because the agency takes a cautious approach to modeling by assuming linear rather than exponential growth (as is often the case with new technologies) and forecasting based on current climate policies rather than more aggressive targets.
This report is a significant stake in the ground for the IEA, and the agency’s serious reputation could help the roadmap become the factual basis for many arguments—policy, legal, and otherwise—against the continued development of fossil fuels.
https://arstechnica.com/?p=1765722