With Tesla’s first Model 3 rolling off the line this month right here in Fremont, it’s no surprise we are following auto tech trends closely. That’s why we’re paying particular attention to thought leaders like Mark Muro, whose recent research on cleantech is especially relevant to our environment. The following article eloquently summarizes auto’s rise to the top in cleantech investment circles.

Mark Muro (@markmuro1) is a senior fellow at the Brookings Institution. Dustin Swonder provided research help on this post. The article “What Patents Reveal About Who’s Behind Clean-Technology Innovation” first appeared on WSJ.com.

Everybody knows the auto industry is a huge source of U.S. manufacturing employment. Now here’s a less-known fact: The auto sector is today also a prime driver of U.S. clean-tech development.

Research my group at Brookings recently released shows that the focus of clean-energy innovation activity is shifting—and making transportation and battery technologies relatively more important. For one thing, innovation in solar, wind, and most other technologies slipped last year, according to our analysis of patent data. Likewise, a related look at venture-capital investments in clean tech revealed similar pullbacks continuing a multiyear decline.

By contrast, auto-company patenting and investment in transportation and energy storage ideas are now driving some of the strongest momentum in clean tech. Nearly one-fifth of all clean-tech patents since 2011 were granted in the transportation sector, and another 15% in energy storage. Transportation reached a new high of 7,433 patents in 2015 and storage hit its all-time high in 2016 with 5,774.

In each area, auto makers and their suppliers were players. Auto-sector companies dominated the list of the largest receivers of patents in the years 2011 to 2016, with GM, Ford, Tesla, TSLA, -0.80% Toyota TM, -0.20% and Delphi DLPH, +0.36% all registering more than 100 patents each over the time period. (GM GM, -0.08% and Ford F, +0.16% each registered more than 1,400.) At the same time, no category of clean tech attracted nearly as much VC funding as the transportation sector, where companies have locked in fundings of $5 billion or more in each the past three years to set new highs. What’s more, while conventional VC firms have been pulling back as investors, automotive firms like BMW have been stepping up to fund innovative startups on their own. Since 2011, auto companies have done 18 VC deals.

As a result, while the pace of innovation has appeared to slow in other categories, the action has picked up on transportation categories and related battery, storage and advanced materials categories. Some of this action reflects continued interest in such key areas as engine efficiency, drivetrain electrification, and the cheap battery technology needed to ensure electric cars catch on. More recently, patenting and VC activity have surged as both traditional auto companies like GM and Ford and their suppliers like Delphi have thrown themselves into an innovation battle with new high-tech competitors like Google GOOG, +0.41% and Apple AAPL, +0.44% and Qualcomm QCOM, +0.16% over newer categories like ride/vehicle sharing, fleet-tracking apps, transportation software and more recently autonomous vehicles—all areas that promise emissions savings and that have technology foundations closely related to the traditional software-based focus on VC investment. As a result, transportation and batteries are now the two hottest zones of innovation in clean tech, along with green materials and energy efficiency.

All of which is a very good thing. Last year, power-sector carbon dioxide emissions fell below transportation-sector emissions for the first time since 1979, meaning that decarbonizing the transportation sector now looms as perhaps America’s top challenge, as the world tries to reduce emissions to fend of severe global warming. Given that, it’s very good to know that America’s once bloated and obtuse auto sector is all over it.