Intel said on Wednesday it will cut its overall greenhouse gas emissions to zero by 2040, the latest pledge by a Silicon Valley giant to address climate change.

The chipmaker's plan means a $300 million investment in energy conservation measures like facility upgrades to reduce power consumption. It also requires changes so chip manufacturing won't release as much carbon dioxide and other greenhouse gases that trap heat from the sun in the Earth's atmosphere.

Intel details its carbon emissions in annual corporate responsibility reports. In its most recent, it estimated its emissions for 2020 to be the equivalent of 3 million metric tons of carbon dioxide. That's equivalent to the emissions produced by more than 646,000 cars each year.

"We are committing to reach net zero greenhouse gas emissions across our operations by 2040," CEO Pat Gelsinger said in a video message about the plan. The emissions reduction will come despite Intel's dramatically expanding operations, including two new "megafab" manufacturing sites the company is building in Ohio and Germany, he said.

Intel's net zero pledge comes after other tech giants have committed to reduce carbon emissions. Two years ago, Apple promised to reach carbon neutrality by 2030, for example. Microsoft is shooting to reach carbon negative by reversing carbon emissions for its corporate lifetime. Google says it's already eliminated its carbon legacy.

Curbing the release of greenhouse gases, particularly carbon dioxide released by burning coal and gasoline, has taken on increasing urgency. Rising temperatures have caused extreme weather events to occur more often, rising sea levels and shrinking biodiversity, according to a February Intergovernmental Panel on Climate Change report reviewing decades of research. Some companies are curtailing emissions to try to help limit global warming to an average of 1.5 degrees Celsius, a goal that has become harder every year but remains with reach.

One challenge Intel faces that most Silicon Valley peers don't is emissions of particularly potent greenhouse gases, including perfluorocarbons it uses to etch circuitry onto microchips. To reduce their climate impact, Intel often burns such gases, says Chief Sustainability Officer Todd Brady. But that still releases carbon dioxide.

"To get to zero, we need to fundamentally think differently about how we've done things so far," Brady said in an interview. The company will push the industry to research and adopt different chemistries for semiconductor manufacturing, he said.

PFCs like sulfur hexafluoride are emitted in relatively small amounts compared with carbon dioxide, but they "are among the most potent greenhouse gases," the US Environmental Protection Agency says. They're typically thousands of times more potent than carbon dioxide, in part because they remain in the atmosphere for thousands of years.

Brady likened the effort to replace PFCs with an earlier chip industry move away from chlorofluorocarbons, which were found to be destroying the Earth's protective ozone layer. Replacing PFCs likely will take a decade, he said.

Cutting greenhouse gas emissions is crucial to combat climate change. Some technology companies like Climeworks, Charm Industrial and CarbonCapture, want to go further by capturing carbon dioxide from the air.

That's been difficult and costly, but a new effort called Frontier, a subsidiary of payments processor Stripe, has secured commitment from Google, Facebook, Shopify and others to spend $925 million on carbon capture services by 2030. 

Intel will cut its direct emissions in other ways. It already uses 100% renewable energy in the US, a practice it will adopt in Israel, Malaysia and other countries.

Reducing a company's climate footprint is complicated. Such efforts have three categories: a company's own direct emissions, called Scope 1; indirect emissions from power the company uses, or Scope 2; and the vastly broader emissions from a company's suppliers and customers, called Scope 3. In Intel's case, that includes factors like materials suppliers' operations and the power consumed by millions of Intel-powered PCs in homes and servers in data centers.

Intel's net zero pledge is aimed only at scopes 1 and 2. The company is working on Scope 3, though, by improving the energy efficiency of its products. It already ranks suppliers in part by scoring their sustainability efforts.

Scope 3 emissions are a big deal. According to Intel's latest corporate responsibility report, Intel's scope 1 and 2 emissions are an equivalent of 3 million metric tons of carbon dioxide per year, but its scope 3 emissions are 30 million metric tons.

Intel already set a earlier goal to increase its main processors' energy efficiency by a factor of 10 by 2030. On top of that, it expects a fivefold efficiency increase with the 2024 release of Falcon Shores, which combines an Intel CPU and graphics chip into a single processing package, compared to earlier PCs with separate graphics chips.

The overall work is expensive but necessary, Brady said.

Doing its part to combat climate change "is probably the biggest challenge...facing mankind right now," he said. Dealing with it is "an expectation from our customers, an expectation from investors and from our employees."