Some people hold the mistaken idea that the only way to solve climate change is to go back to a stone age style of living—maybe bronze age if we’re careful. While that’s not true, describing the necessary changes to our energy system can leave you imagining that we need an all-out moonshot—or several.

There has even been criticism of whether the scenarios that limit global warming to 2°C are plausible, given that they rely on large-scale, active removal of CO 2 from the atmosphere. But an interesting new scenario published this week shows that even greater climate progress could be achieved without a single carbon capture plant, all while improving the global standard of living. The key to the new plan is efficiency.

The 2015 Paris Agreement affirmed the international intent to limit global warming to 2°C and added a new goal to stay under 1.5 °C. But accomplishing this is increasingly unlikely without a drastic change in emissions trends. While improving efficiency has always been an important part of the puzzle, a study led by Arnulf Grubler of the International Institute for Applied Systems Analysis shows just how far you can take it if you really dig into what it means to be efficient. Their answer is that it can get to you 1.5°C.

Living standards up, energy down

Here’s what this idealized, smarter, more efficient world would look like by 2050: The general themes are electrification of everything possible, more renewable energy (including more small-scale systems like home solar panels), much less energy wasted by devices and homes, expanding the sharing economy, and continuing to go digital. You may not realize it, but the majority of energy is lost as waste heat before it can do anything we care about. Between minimizing the losses and getting more value out of the end products, huge reductions in total energy use are possible.

The researchers emphasize that this scenario results in similar or improved standards of living compared to scenarios of higher emissions. They also focus on accelerating trends we’ve already seen rather than more speculative changes in energy use. The global average amount of per-person living space rises to the current Northern Hemisphere average, for example—representing massive progress in the South—but efficient construction and retrofitting drives total home energy use down.

Access to consumer devices and appliances goes up around the world, but efficiency gains lower the total energy use. Here, the researchers highlight an interesting way to look at smartphones—as incredibly efficient replacements for a range of devices. A capable phone can be a camera, radio, alarm clock, GPS navigator, and even TV. That means you could buy and operate a phone instead of all those things, accessing the same lifestyle with a fraction of the energy use.

In the transportation sector, the scenario sees a widespread switch to electric vehicles, increases in public transport and other forms of “shared mobility” (think your favorite ride-sharing app), and some substitution of virtual presence for travel. Again, access to transportation improves a little in the Northern Hemisphere and a lot in the Southern Hemisphere, but the total energy shrinks.

Industry also gets more efficient, using about 20 percent less energy than it does now. That’s largely due to reducing waste and losses, but there’s another notable trend: demand for raw materials goes down as we get a little more value out of each thing we produce.

Finally, food supply improves even as the global population grows 20 percent. One of the forms of CO 2 removal relied on in other scenarios is the growing of biofuel crops to be burned in plants that capture the CO 2 emissions and injecting that in the ground. Growing biofuel crops competes with food crops for land, though, so excluding biofuels makes it easier to grow enough food. In this scenario, it even allows some cropland to be reforested—which itself removes some CO 2 from the atmosphere.

Targeting 1.5ºC

In total, taking efficiency this far reduces global energy use to just 60 percent of what we use today. It’s much easier to dump coal and build up renewables to hit that number. As a result, greenhouse gas emissions fall quickly enough in this scenario to put us on track for about 1.5°C warming, which is far better than the three-plus degrees current emissions pledges would get us to. In addition to improved access to many services and reduced climate impacts, that model obviously comes with sizable environmental health benefits like improved air quality.

There are certainly potential roadblocks to that rosy outcome. A car with improved fuel efficiency, for example, can often make a person drive more as they have gas money to spare. It’s a water-treading conundrum known as the “rebound effect” that the researchers’ acknowledge could eat into their results. But they point out that demand for many things could be nearly maxed out, citing the falling per-person electricity use in California and a lower percentage of younger Americans getting drivers’ licenses. They also note that we’re not entirely helpless in the face of the rebound effect—governments can apply tax policies that affect demand, for example.

There is also no insight into the economic ramifications of a more-efficient world. More efficient use (including sharing) of products likely hurts the revenue of manufacturers unless they can adapt their business model. And lower demand for raw materials would affect prices and extraction industries. It’s not obvious how all these trends would shake out.

At least in principle, though, this study shows that aiming for a smarter, more efficient world has the potential to help write a story with a much happier ending than some of the other drafts we’ve seen. The standard of living many people currently enjoy can be sustained with considerably less energy than we’re currently fueling it with—making it considerably more sustainable.

Nature Energy, 2018. DOI: 10.1038/s41560-018-0172-6 (About DOIs).