Video game developers are starting to grapple with the real-life, planet-warming consequences of immersing gamers in fantasy worlds.

The Washington Post says: More than 3 billion people — a third of humanity — play video games.

Their consoles, computers, tablets and smartphones use more electricity than midsize countries.

Video games in the United States alone create more greenhouse pollution than 5 million cars. And the legion of gamers and power-hungry devices is only expected to grow.

More efficient and sustainable games

To limit the impact on the environment and strained electric grids, blockbuster studios and independent artists are looking for ways to make their games more efficient — without turning off a passionate fan base known for obsessing over the way their games look and perform.

The studios behind Fortnite, Minecraft, Call of Duty, Halo, the Elder Scrolls and other popular titles have announced tweaks this year to make their games hog less power. Xbox and PlayStation both updated their consoles to use much less electricity when they’re idle, and Xbox now schedules software updates for moments when there’s more renewable energy on the local power grid.

Each console maker says it’s preventing the greenhouse gas equivalent of taking tens of thousands of cars off the road every year.

Meanwhile, the United Nations has created the Playing for the Planet Alliance, an industry group that hosts “Green Games Jams” to encourage developers to make games that educate players on climate change, and is working on voluntary standards to track games’ carbon emissions.

“Wasting energy and wasting money is silly,” said Trista Patterson, who heads sustainability work at Xbox. She added, “Anyone who is looking for the most advanced gaming experience does not want a piece of hardware that is running hotter or consuming more energy with absolutely no change to their experience.”

Still, the moves have attracted controversy. In January, conservative commentators and politicians accused Xbox of making video games “woke” after it released an optional power-saving mode.

And even those pushing for greener games acknowledge there’s only so much the industry can do to trim their electricity use. The ultimate fix would be a power grid that runs on renewable energy. “We’re not going to get to net zero just by finding efficiencies,” said Ben Abraham, who heads research at the nonprofit Sustainable Games Alliance.

An energy arms race

Most of gaming’s greenhouse emissions come from the electricity players use to power their consoles, computers and mobile devices, according to a U.N. report. At-home energy use dwarfs the climate impact from assembling consoles, running data centers and powering the offices where developers work.

Computers and consoles have been using ever more computing power as companies compete to offer the latest graphics. The number of pixels a cutting-edge console can pack into a screen has leaped from 2 million to 8 million to 33 million in a little more than a decade. Even as consoles have gotten more efficient, the power needed to play the latest games has continued to rise.

“That upgrade cycle is embedded in the games industry’s marketing and business model, and that puts us on this unsustainable treadmill of forever upgrades … even as we’re reaching the point of total diminishing returns,” said Abraham.

Although a vocal contingent of hardcore fans fawn over minute improvements in lighting effects, “it’s really pandering to a minority of gamers,” said Kara Stone, an assistant professor of design at Alberta University of the Arts. “Most people playing games don’t really care.”

The majority of gamers play on mobile devices. Because players don’t want games to drain their battery or heat up their smartphones or tablets, developers work hard to make mobile games run using less power. Similarly, the Nintendo Switch — a console that also works as a handheld mobile device — uses less than a tenth as much power as the plug-in PlayStation or Xbox.

“The Nintendo Switch is so energy-lean already,” said Sam Barratt, who founded the UN’s Playing for the Planet Alliance. But lately, he said, Nintendo’s rival consoles, Microsoft’s Xbox and Sony’s PlayStation, “are really thinking quite hard about how they can provide games that are efficient.”

Pressing pause on energy use

Recognizing the outsize role consoles and computers play in creating video game emissions, Xbox created a set of tools for developers to track how much power their games use and cut back on energy in places gamers probably won’t notice.

When someone pauses a game of “Halo Infinite,” for example, a settings menu pops up and covers the entire screen. But until recently, the game would still devour electricity to generate detailed scenery in the background, “despite the fact that our players couldn’t even see these assets,” Halo developers wrote in a recent case study.

This year, “Halo Infinite” started lowering the graphics resolution when a player hits pause, which cut energy use 15 percent. “You would be surprised how much time players spend on menus and how much power savings you can gain with that simple implementation,” said Spencer Kopach, a developer at Halo Studios.

Other studios have also realized their games were using as much or even more power to display menu screens as they were during intense gameplay.

Fortnite pared back the graphics quality while players are in online “lobbies” waiting for a game to start, and it saved 200 megawatt-hours of electricity per day — the average output of seven U.S. wind turbines.

The Elder Scrolls Online throttled graphics when players open menu screens or go idle for five minutes, and its developers reported a 5 percent drop in overall energy use — which they estimate will save the emissions equivalent of burning 1 million pounds of coal over the next three years just for Xbox users.

So far, these steps have targeted the smallest and most imperceptible changes. But even then, players don’t always go along with it.

Earlier this year, the developers behind Call of Duty introduced a default “Eco Mode” that pares back graphics when players open menus or wait in lobbies. Within two months of its release, nearly 1 in 10 console gamers and 1 in five PC gamers manually turned off the power-saving mode.

Abraham took a glass-half-full view of those results. “It’s encouraging that it’s only 10 or 20 percent,” he said. “Given the perception of gamers as basement-dwelling troglodytes that only care about headshots, I think we’re doing all right.”

A new model for gaming

While big studios take small steps toward efficiency, independent developers are testing experimental games that create as few emissions as possible.

Stone, the Canadian design professor, released an online game last month that runs on a web server powered entirely by a solar panel she installed on her apartment balcony. It’s an attempt to prove that gaming is compatible with fighting climate change.

“There are creative approaches that studios and designers can take to make really beautiful and fun and engaging games that also aren’t as high-carbon,” she said.

The game, “Known Mysteries,” features low-fi graphics, heavily compressed video and simple gameplay to allow it to fit into bite-sized data files. It should be available any time, since Stone hooked her solar panel up to a secondhand boat battery to keep the server running overnight. But, if it goes down, she doesn’t mind.

“That’s part of the project,” she said.

Stone knows professional game studios can’t all run their servers on DIY solar panels. But it’s a way to imagine what a climate-friendly future of gaming might look like — one where games use energy more thoughtfully, and all the equipment runs on renewable electricity.