Hitting the Books: Bill Gates on why we can't have electric airplanes

Or long-haul cargo ships, for that matter.

·6 min read

The renaissance of electrification that we're seeing in passenger vehicles unfortunately won't likely adapted to heavier forms of transportation — such as airplanes, cargo ships and semi tractor trailers — in the foreseeable future. Today's batteries simply can't hold enough power to sufficiently offset their weight and bulk. But that doesn't mean that we can't still take steps to reduce the carbon footprints of our commercial people and cargo movers.

In his new book, How to Avoid a Climate Disaster: The Solutions We Have and the Breakthroughs We Need, tech luminary Bill Gates — with the help of countless subject matter experts — lays out his comprehensive plan to halt the oncoming environmental apocalypse, blunt the effects of human-caused climate change, and keep Earth habitable for the next generation.

How to Avoid a Climate Disaster by Bill Gates
How to Avoid a Climate Disaster by Bill Gates (Penguin Randomhouse)

Adapted from How to Avoid a Climate Disaster: The Solutions We Have and the Breakthroughs We Need by Bill Gates, published on Feb. 16, 2021 by Alfred A. Knopf, an imprint of the Knopf Doubleday Publishing Group, a division of Penguin Random House LLC. Copyright © 2021 by Bill Gates.

Not long ago, my friend Warren Buffett and I were talking about how the world might decarbonize airplanes. Warren asked, “Why can’t we run a jumbo jet on batteries?” He already knew that when a jet takes off, the fuel it’s carrying accounts for 20 to 40 percent of its weight. So when I told him this startling fact — that you’d need 35 times more batteries by weight to get the same energy as jet fuel — he understood immediately. The more power you need, the heavier your plane gets. At some point, it’s so heavy that it can’t get off the ground. Warren smiled, nodded, and just said, “Ah.”

When you’re trying to power something as heavy as a container ship or jetliner, the rule of thumb I mentioned earlier — the bigger the vehicle you want to move, and the farther you want to drive it without recharging, the harder it’ll be to use electricity as your power source—becomes a law. Barring some unlikely breakthrough, batteries will never be light and powerful enough to move planes and ships anything more than short distances.

Consider where the state of the art is today. The best all-electric plane on the market can carry two passengers, reach a top speed of 210 miles per hour, and fly for three hours before recharging.* Meanwhile, a mid-capacity Boeing 787 can carry 296 passengers, reach up to 650 miles an hour, and fly for nearly 20 hours before stopping for fuel. In other words, a fossil-fuel-powered jetliner can fly more than three times as fast, for six times as long, and carry nearly 150 times as many people as the best electric plane on the Market.

Batteries are getting better, but it’s hard to see how they’ll ever close this gap. If we’re lucky, they may become up to three times as energy dense as they are now, in which case they would still be 12 times less energy dense than gas or jet fuel. Our best bet is to replace jet fuel with electrofuels and advanced biofuels, but there are hefty premiums that come with them.

The same goes for cargo ships. The best conventional container ships can carry 200 times more cargo than either of the two electric ships now in operation, and they can run routes that are 400 times longer. Those are major advantages for ships that need to cross entire oceans.

Given how important container ships have become in the global economy, I don’t think it will ever be financially viable to try to run them on anything other than liquid fuels. Making the switch to alternatives would do us a lot of good; because shipping alone accounts for 3 percent of all emissions, using clean fuels would give us a meaningful reduction. Unfortunately, the fuel that container ships run on — it’s called bunker fuel — is dirt cheap, because it’s made from the dregs of the oil refining process. Since their current fuel is so inexpensive, the Green Premium for ships is very high.

Would most people be willing to accept these increases? It’s not clear. But consider that the last time the United States raised the federal gas tax — imposed any increase at all — was more than a quarter century ago, in 1993. I don’t think Americans are eager to pay more for gas.

There are four ways to cut down on emissions from transportation.

One is to do less of it — less driving, flying, and shipping. We should encourage more alternative modes, like walking, biking, and carpooling, and it’s great that some cities are using smart urban plans to do just that.

Another way to cut down on emissions is to use fewer carbon-intensive materials in making cars to begin with —although that wouldn’t affect the fuel-based emissions we’ve covered in this chapter. Every car is made from materials like steel and plastics that can’t be manufactured without emitting greenhouse gases. The less of these materials we need in our cars, the lower their carbon footprint will be.

The third way to cut down on emissions is to use fuels more efficiently. This subject gets a lot of attention from lawmakers and the press, at least as it pertains to passenger cars and trucks; most major economies have fuel efficiency standards for those vehicles, and they’ve made a big difference by forcing car companies to fund the advanced engineering of more efficient engines.

But the standards don’t go far enough. For example, there are suggested emissions standards for international shipping and aviation, but they’re almost unenforceable. Which country’s jurisdiction would cover carbon emissions from a container ship in the middle of the Atlantic Ocean?

Besides, although making and using more efficient vehicles are important steps in the right direction, they won’t get us to zero. Even if you’re burning less gasoline, you’re still burning gasoline.

That brings me to the fourth — and most effective — way we can move toward zero emissions from transportation: switching to electric vehicles and alternative fuels.

We can speed up the transition by adopting policies that encourage people to buy EVs and creating a network of charging stations so they’re more practical to own. Nationwide commitments can help drive up the supply of cars and drive down their cost; China, India, and several countries in Europe have all announced goals to phase out fossil-fueled vehicles — mostly passenger cars — over the coming decades. California has committed to buying only electric buses by 2029 and to banning the sale of gas-powered cars by 2035.

Next, to run all these EVs we hope to have on the road, we’ll need a lot of clean electricity—one more reason why it’s so important to deploy renewable sources and pursue breakthroughs in generation and storage.

Finally, we need a massive effort to explore all the ways we can make advanced biofuels and cheap electrofuels. Companies and researchers are exploring several different pathways—for example, new ways to make hydrogen using electricity, or using solar power, or using microbes that naturally produce hydrogen as a by-product. The more we explore, the more opportunities we’ll create for breakthroughs.