Getting to Net-Zero, in the U.S. and the World

Photo of wind turbines

Princeton University’s Jesse Jenkins, assistant professor of mechanical and aerospace engineering and the Andlinger Center for Energy and the Environment, has been a leader of both the national and the global charge to net-zero, along with his Net-Zero America project collaborators including Chris Greig and Eric Larson

Some of Jenkins’ research has been key to shaping national climate legislation, including the Inflation Reduction Act (IRA) and the Infrastructure Investment and Jobs Act. This summer, The Wall Street Journal profiled Jenkins and the impact his ZERO Lab has had on national climate policy, noting that the group’s work “was widely cited by the White House and media organizations” in the run-up to the passage of the climate measures in the IRA. The lab “has become an important place for data and analysis of the energy transition,” the Journal reported.

Headshot of Jesse Jenkins Jesse Jenkins

Photo byFrank Wojciechowski

“Net-zero” is the shorthand for the goal of having a net total of zero new tons of greenhouse gases emitted into the world’s atmosphere each year. To meet that goal requires both getting emissions as low as possible and removing as much carbon dioxide as we continue emitting — either through natural solutions like planting trees or with technological approaches.

Here, Jenkins shares what’s been achieved in the last few years since Princeton’s groundbreaking Net-Zero project — and with the passage of the IRA — and looks ahead to the biggest challenges left to solve.

You and your colleagues modeled five pathways to net-zero in the 2020 Net-Zero America project. How much progress have we made? What’s left to do?

We’ve really come a long way. If you think about the kinds of technologies we said we’d need to develop in this decade in order to be ready for wide-scale use in the 2030s and 2040s — if you go down that list, we now have policy support for almost all of them.

We’ve got new provisions and strong grant programs for clean hydrogen, carbon capture, direct air capture, carbon-free clean fuels, advanced nuclear, the full list of novel technologies. That’s really encouraging because none of that existed when we put the report out.

Next, we have to deploy trillions of dollars of capital to build clean energy infrastructure at scale. The Inflation Reduction Act is driving that transformation now, with somewhere on the order of half a trillion dollars in public spending, which will probably induce a couple of trillion dollars in total capital investment — largely in line with the scale that we need for a net-zero pathway.

Most of that funding is going to mature technologies: wind and solar (and the transmission distribution grid upgrades that we need to deploy them), electric vehicle incentives, energy efficiency and electrification. If you take all that in, we’ve come a huge distance.

What still needs to be done?

Upgrading our electrical infrastructure.

The electricity sector is the critical linchpin in the net-zero path. Electricity itself is responsible for about a quarter of our emissions, so you’ve got to eliminate those. Plus we want to fuel electric vehicles and heat pumps, produce clean hydrogen, directly electrify industrial process heat, run direct air capture facilities — all with clean electricity. Electricity-consuming technologies are key to decarbonizing other sectors.

That creates a critical, dual challenge in the electricity sector: We have to cut emissions faster and deeper than any other sector, and do that while simultaneously expanding electricity supply quite substantially — by 25% by 2030, 50% by 2035, and 150%, give or take, by 2050.

Our electrical demand will more than double over the next two and a half decades, so that’s an enormous challenge. We’re not going to be able to get there, to both build clean energy and more than double our electricity supply, with today’s electricity, transmission and distribution grid.