Fork and Koningstein reported in late June, 2021 that seven years ago, we published an article in IEEE Spectrum titled “What It Would Really Take to Reverse Climate Change.” We described what we had learned as Google engineers who worked on a well-intentioned but ultimately failed effort to cut the cost of renewable energy. We argued that incremental improvements to existing energy technologies weren’t enough to reverse climate change, and we advocated for a portfolio of conventional, cutting-edge, and might-seem-crazy R&D to find truly disruptive solutions. We wrote: “While humanity is currently on a trajectory to severe climate change, this disaster can be averted if researchers aim for goals that seem nearly impossible. We’re hopeful, because sometimes engineers and scientists do achieve the impossible.”
Today, still at Google, we remain hopeful. And we’re happy to say that we got a few things wrong. In particular, renewable energy systems have come down in price faster than we expected, and adoption has surged beyond the predictions we cited in 2014.
Our earlier article referred to “breakthrough” price targets ( modeled in collaboration with the consulting firm McKinsey & Co.) that could lead to a 55 percent reduction in U.S. emissions by 2050. Since then, wind and solar power prices have met the targets set for 2020, while battery prices did even better, plummeting to the range predicted for 2050. These better-than-expected price trends, combined with cheap natural gas, caused U.S. coal usage to drop by half. The result: By 2019, U.S. emissions had fallen to the level that the McKinsey scenario forecast for 2030—a decade sooner than our model predicted. And thanks to this progress in decarbonizing electricity production, engineers are seeking and finding numerous opportunities to switch existing systems based on the combustion of fossil fuels to lower-carbon electricity. For example, electric heat pumps are becoming a cost-effective replacement for heating fuel, and electric cars are coming down in price and going up in range.
Even with all this progress, though, we’re still on a trajectory to severe climate change: a 3°C rise by 2100. Many countries are not meeting the emissions reductions they pledged in the 2015 Paris Agreement. Even if every country were to meet its pledge, it would not be enough to limit planetwide warming to 1.5 °C, which most experts consider necessary to avoid environmental disaster. Meeting pledges today would require a drastic slashing of emissions. If these wholesale emission reductions don’t happen, as we think likely, then other strategies will be needed to keep temperatures within bounds.
The levelized cost of energy describes the costs of building and operating power plants over their lifetimes, measured in U.S. dollars per megawatt-hour. Since 2009, the cost of solar photovoltaic (PV) and wind power have decreased rapidly. Battery storage capacity prices have plummeted even faster.
Here are some key numbers: To reverse climate change, even partially, we’ll need to bring atmospheric carbon dioxide levels down to a safer threshold of 350 parts per million; on Earth Day 2021 the figure stood at 417 ppm. We estimate that meeting that target will require removing on the order of 2,000 gigatonnes of CO2 from the atmosphere over the next century. That wholesale removal is necessary both to draw down existing atmospheric CO2 as well as the CO2 that will be emitted while we transition to a carbon-negative society (one that removes more carbon from the atmosphere than it emits).
Our opening battles in the war on climate change need engineers to work on the many existing technologies that can massively scale up. As already illustrated with wind, solar, and batteries, such scale-ups often bring dramatic drops in costs. Other industrial sectors require technological revolutions to reduce emissions. If you experiment with your own mix of climate-mitigation techniques using the En-ROADS interactive climate tool, you’ll see how many options you have to max out to change our current trajectory and achieve 350 ppm CO2 levels and a global temperature rise of no more than 1.5 °C.
So what’s an engineer who wants to save the planet to do? Even as we work on the changeover to a society powered by carbon-free energy, we must get serious about carbon sequestration, which is the stashing of CO2 in forests, soil, geological formations, and other places where it will stay put. And as a stopgap measure during this difficult transition period, we will also need to consider techniques for solar-radiation management—deflecting some incoming sunlight to reduce heating of the atmosphere. These strategic areas require real innovation over the coming years. To win the war on climate change we need new technologies too.
We’re optimistic that the needed technology will emerge within a couple of decades. After all, engineers of the past took mere decades to design engines of war, build ships that could circle the globe, create ubiquitous real-time communication, speed up computation over a trillionfold, and launch people into space and to the moon. The 1990s, 2000s, and 2010s were the decades when wind power, solar power, and grid-scale batteries respectively started to become mainstream. As for which technologies will define the coming decades and enable people to live sustainably and prosperously on a climate-stable planet, well, in part, that’s up to you. There’s plenty to keep engineers hard at work. Are you ready?
Before we get to the technology challenges that need your attention, allow us to talk for a moment about policy. Climate policy is essential to the engineering work of decarbonization, as it can make the costs of new energy technologies plummet and shift markets to low-carbon alternatives. For example, by 2005, Germany was offering extremely generous long-term contracts to solar-energy producers (at about five times the average price of electricity in the United States). This guaranteed demand jump-started the global market for solar photovoltaic (PV) panels, which has since grown exponentially. In short, Germany’s temporary subsidies helped create a sustainable global market for solar panels. People often underestimate how much human ingenuity can be unleashed when it’s propelled by market forces.
Read on. Interesting article ...........................................
Re role of nuclear power ......
The authors later indicate that "while we consider those options, we’ll also need to make sure those sources of energy are steady and reliable. Critical infrastructure such as hospitals, data centers, airports, trains, and sewage plants need around-the-clock electricity. (Google, for one, is aggressively pursuing 24/7 carbon-free energy for its data centers by 2030.) Most large industrial processes, such as the production of glass, fertilizer, hydrogen, synthesized fuels, and cement, are currently cost-effective only when plants are operated nearly continuously, and often need high-temperature process heat.
To provide that steady carbon-free electricity and process heat, we should consider new forms of nuclear power. In the United States and Canada, new policies support advanced nuclear-energy development and licensing. Dozens of advanced nuclear-fission companies offer engineers a variety of interesting challenges, such as creating fault-tolerant fuels that become less reactive as they heat up. Other opportunities can be found in designing reactors that recycle spent fuel to reduce waste and mining needs, or that destroy long-lived waste components via new transmutation technologies.(SMRs)
Engineers who are drawn to really tough quests should consider nuclear fusion, where the challenges include controlling the plasma within which the fusion occurs and achieving net electric power output. This decade’s competition in advanced nuclear-energy technologies may produce winners that get investors excited, and a new round of policies could push these technologies down the cost curve, avoiding a lost decade for advanced nuclear energy."(more)