Climate Change: The Technologies That Could Make All the Difference

The Wall Street Journal recently asked energy academics and researchers which specific climate-technology breakthroughs they think have the potential to be most transformative. Some talked about technologies on the horizon; others focused on existing technologies that could be deployed to help get the world to zero emissions by 2050.

Here is what they said about the technologies that they believe have the most promise:

The Heat Under Our Feet

Joan Fitzgerald is a professor in the School of Public Policy and Public Affairs at Northeastern University and the author of “Greenovation: Urban Leadership on Climate Change.”

When it comes to renewables, most people think of wind and solar. But there is another renewable-energy technology used for heating and cooling that doesn’t always get the appreciation it deserves: ground-source heat pumps.

These systems, which draw heat out of the ground to heat buildings in winter and pump heat from buildings back into the ground to cool them in summer, are four to five times more efficient than fossil-fuel systems, and the energy isn’t intermittent like it is with wind and solar. Geothermal heat pumps can be configured into networks that connect buildings on a street, moving energy on demand or storing it when it isn’t needed.

Networked heat pumps aren’t new—they already are used on numerous college campuses—but recent breakthroughs could be transformative if the right policies are put in place.

In Massachusetts, HEET, a nonprofit seeking to reduce fossil-fuel emissions, is working with two of the state’s largest natural-gas utilities to install and test networked heat pumps in neighborhoods, in the hopes of scaling the technology. A three-year Eversource project will connect about 100 homes and businesses, starting this summer. Four National Grid pilots announced in February will explore implementation in different types of neighborhoods. Changing the regulatory structure to allow gas utilities to sell thermal energy is now on the agenda at the Massachusetts Legislature.

A Massachusetts feasibility study estimates that converting neighborhoods from natural gas to networked heat pumps could reduce greenhouse-gas emissions from heating, cooling and domestic hot water in those areas by more than 90% by 2050. To achieve this dramatic result, policy and planning breakthroughs will be key.

A Better Air Conditioner

Caroline Winslow and Radhika Lalit are managers at RMI (formerly Rocky Mountain Institute), an independent nonprofit focused on decarbonizing the global energy system.

Most people think of residential room air conditioners as just another household appliance. In reality, the increased adoption of space cooling, especially in the developing world, represents one of the single largest end-use risks to our global climate goals.

There is a solution, however. New, highly efficient AC units under development could become powerful tools for both mitigating and adapting to a warming climate, all while giving people access to a better quality of life.

In 2018, a competition to find climate-friendly cooling technologies that could be commercialized and brought to market in the next few years was initiated by our company, RMI, and another nonprofit, Mission Innovation, along with the Indian government. The winning prototypes—from Japanese manufacturer Daikin Industries 6367 -1.32% and partner, Nikken Sekkei Ltd., and Chinese manufacturer Gree Electric Appliances Inc. 000651 2.53% and partner, Tsinghua University—combined hybrid vapor compression systems with more climate-friendly refrigerants to create highly efficient room ACs with an 80% lower climate impact than a typical model on the market today. The higher incremental cost of such super-efficient units would have a payback period of less than three years due to energy savings, RMI estimated.

If left unchecked, room air conditioners alone could add around 132 gigatons of cumulative carbon-dioxide-equivalent emissions globally by 2050, approaching the expected cumulative emissions of the U.S. from all end uses over the same period. But new AC models, when scaled, have the potential to mitigate up to half a degree Celsius of warming by 2100, all while closing the critical cooling-access gap.

The Big Three

Gregory Nemet is a professor at the University of Wisconsin–Madison’s La Follette School of Public Affairs whose research focuses on the process of technological change in energy and its interactions with public policy.

To get the world economy to zero emissions by midcentury, we need to move light and fast. That means aggressively expanding what we know works and is affordable—wind, solar and electric vehicles—on the order of how quickly we built ships and airplanes in World War II. Falling prices, digitization of the economy and more flexible electric grids can enable us to do that.

The “big three” have improved dramatically over the past 10 years—solar and batteries for electric vehicles are 90% cheaper, while wind power is 50% cheaper. Although wind and solar aren’t available at all times, an emerging combination of technologies is enabling reliable power systems with high amounts of variable renewables. These systems include batteries and other energy storage; new transmission; combining diverse renewables; programs to reduce energy use during peak periods; improved forecasting; and some limited backup, such as nuclear and natural gas with carbon capture. This increasingly clean electric grid, combined with the steadily falling cost and growing adoption of EVs, also is on its way to becoming the core of a clean transportation sector.

Digitization of the economy is helping to fuel this transformation by, among other things, making the electric grid smart and offering ways to substantially reduce material and energy consumption, for example through shared mobility.

To be sure, large-scale technologies like hydrogen, nuclear and carbon-removal technologies such as direct air capture can play a role in helping us meet climate goals, as could blocking sunlight by injecting aerosols in the stratosphere. But beyond a supporting role, these are risky bets compared with aggressively scaling up what we know works and is affordable.

A Leap for Nuclear

Seaver Wang is co-director of the Climate and Energy Program at the Breakthrough Institute, a global research center that promotes technological solutions to environmental and human-development challenges.

The first reactor unit at the Shidao Bay next-generation nuclear power plant in eastern China went live in December. The milestone was met with little fanfare, but future generations may see it as a landmark leap for clean energy.

The small, innovative 200-megawatt reactor is exciting because in addition to clean electricity, it produces high-temperature heat that could be used to help decarbonize energy-intensive industries that lack ready clean-energy alternatives.

Most conventional reactors today produce outlet steam at temperatures of up to 300 degrees Celsius, which can power industrial processes such as seawater desalination and hydrogen electrolysis, in which water is split into hydrogen and oxygen. The Shidao Bay reactor—which uses spherical fuel pebbles coated in graphite as an energy source and pressurized helium as a coolant—generates steam at outlet temperatures of about 560 degrees Celsius, which potentially could power even more processes, such as plastics production and more-efficient hydrogen production via high-temperature water splitting. Such technology could even facilitate replacement of coal-fired generating units with nuclear reactors, enabling more extensive re-use of existing power-plant steam infrastructure.

Given China’s coal-heavy power grid, the successful deployment of this reactor offers hope that advanced nuclear could make a big difference for the climate in the world’s highest-emitting country and beyond. The reactor is smaller, potentially making it easier to build and more adaptable to varying energy needs, and sets a new standard in improved safety, thanks in part to its simplicity of design and highly heat-resistant fuel. Finally, China’s notable recent successes in building nuclear projects overseas means the technology might spread world-wide faster than many expect.

Cleansing the Air

Michael E. Webber is a professor of energy resources at the University of Texas and the chief technology officer at the venture fund Energy Impact Partners.

Technologies that remove carbon-dioxide from the atmosphere are helpful if we want to get to net-zero emissions, and critical if we want to drive down CO2 levels to where they were before the Industrial Revolution.

There are several approaches to carbon removal, such as planting more trees, sequestering carbon in soils and directly capturing CO2 from the atmosphere with machines. This last option, known as direct air capture (or DAC), is particularly powerful because the technology is modular, which means we can make many copies of the same design, and it can be deployed anywhere.

Unlike other pollutants, what matters with carbon dioxide isn’t the location of its release but the total atmospheric accumulation. Releasing greenhouse gases in industrial corridors and then removing them from the atmosphere in remote locations has essentially the same net effect as if the carbon wasn’t emitted in the first place. That means we can deploy DAC systems wherever the energy for their operation is cheapest, ecosystem impacts are lowest, and the economic activity would be welcome.

The modularity of DAC systems implies that costs for CO2 removal might drop 90% to 95% over a couple of decades, just like the recent cost declines for other modular solutions such as wind turbines, solar panels and lithium-ion batteries.

This isn’t a fantasy: In September 2021, Iceland started deploying geothermal energy to power a DAC system that removes CO2 and permanently sequesters it below ground. Now that we know it works, it is a matter of scaling up. There are many innovative companies in this space, so that means figuring out collectively how to lower the cost and energy requirements for carbon removal—whether it be from clever engineering, novel scrubbing materials or whole new approaches—and then deploying as many of that design as possible.

Solar Microgrids

Alexandra von Meier is an adjunct professor in the department of electrical engineering and computer science at the University of California, Berkeley. She also directs the Electric Grid Research program at the California Institute for Energy and Environment and the Center for Information Technology Research in the Interest of Society (Citris).

Climate technologies are more likely to go viral if they also address pain points energy consumers face today. Solar microgrids, helped by information technology, have the potential to be such a solution, able to accomplish climate mitigation and adaptation at the same time.

What do people really want when it comes to energy? Security. That means health and safety, comfort, and knowing that your essential needs will be covered even during a crisis, such as a power outage associated with an extreme weather event or wildfire.

A solar microgrid, which generates, stores and distributes clean energy to homes and facilities in a local network, provides a strong answer to these needs and wants. It can integrate with the main electric grid or disconnect and operate autonomously if the main grid is stressed or goes down. The physical pieces—solar panels, batteries and inverters—have been improving for a while. What’s new and coming, though, is the ability to orchestrate these different pieces into agile electric grids.

With digital tools and data science, demand for energy can now be sculpted locally to match available resources, reducing the number of power plants that utilities need to keep in reserve. The key is giving consumers the ability to separate flexible energy uses—say, operating a Jacuzzi—from essential needs, which can now be done with phone apps for smart appliances and service panels.

Meanwhile, connections between groups of customers can be opened and closed as needed with modern, communicating circuit switchgear. On most days, solar microgrids will stay connected to the main grid, importing or exporting power as needed to help balance the load. During emergencies, though, they can operate safely as power islands of different sizes to sustain vital services.

Such adaptability will unlock the priceless benefits of local security, while continuing to allow access to inexpensive bulk energy through the macro-grid. In this way, solar microgrids can become a flexible and affordable solution to our climate challenges.

Enhanced Energy Storage

Amy Myers Jaffe is a research professor and managing director of the Climate Policy Lab at the Fletcher School at Tufts University.

Batteries are a critical technology for expanding renewable-energy use, collecting solar and wind power at times of low demand so it can be redeployed later when more electricity is needed.

The good news is that record amounts of batteries are being installed in U.S. homes and on the electric grid, despite supply-chain bottlenecks. The bad news is that current battery technology only offers a few hours of storage. What’s needed are more-powerful battery systems that can extend the length or scale of storing, which could be even more enabling to sun and wind power.

Two such solutions are on the horizon. Stationary metal-air batteries, such as iron-air batteries, don’t hold as much energy per kilogram as lithium-ion batteries so it takes a larger, heavier battery to do the job. But they are cheaper, iron is a plentiful metal, and the batteries, whose chemistry works via interaction of the metal with air, can be sized and installed to store and discharge a large level of electricity over days or weeks. While not an option for cars due to heavy weight and size, improved large iron-air batteries are poised to become a great new backup for renewable energy within the next couple of years to address those times of year when drops in renewable energy production can last for days and not hours.

For households, a battery configuration called a virtual power plant also holds huge potential to extend the use of renewables. These systems allow a local utility or electricity distributor to collect excess energy stored in multiple households’ battery systems and feed it back to the grid when there is a surge in demand or generation shortfall.

Greener Shipping

Ingrid Irigoyen is the director and Taylor Goelz the program manager of the Aspen Institute Shipping Decarbonization Initiative.

Maritime shipping is considered challenging to decarbonize because of the industry’s global, distributed nature and a lack of ready clean-energy alternatives. But thanks to promising emerging technologies, as well as growing public pressure and regulatory interest, investment in zero-emissions shipping is starting to heat up.

Electrification is a good choice for smaller vessels on short voyages, like the world’s largest all-electric ferry launched in Norway in 2021. It isn’t yet a viable option for ships on transoceanic voyages because batteries are still too large and heavy, though innovative approaches for battery swapping are being explored.

For longer voyages, e-ammonia, a hydrogen-derived fuel made with renewable energy, has been identified as a prime candidate, although work is needed to ensure safety. Ammonia has a higher energy density than some other options, making it a more economical option for powering large ships across oceans. It also has potential for lower life-cycle emissions if renewable energy is used as an energy source. Among ammonia projects in the works, MAN Energy Solutions is developing engines that can run on conventional fossil fuel or ammonia, a coalition of Nordic partners is designing the world’s first ammonia-powered vessel, and Singapore is evaluating how to bunker the fuel.

Others in the industry are investing in green fuels that may be ready for deployment sooner, such as e-methanol, which can be made by combining renewable-energy-generated hydrogen with carbon from direct air capture or biogenic sources. Most studies, however, predict e-ammonia outcompeting e-methanol on cost in the long term.

Policy support, cross-sector collaboration and private investment will be needed to deploy and rapidly scale these solutions, but the payoff could be significant. Maritime shipping currently emits approximately 1 billion tons of greenhouse gases a year, equivalent to the emissions from all U.S. coal-fired power plants combined. Without intervention, shipping’s emissions footprint could triple by 2050, threatening achievement of Paris Agreement goals.

Innovation in EV Batteries

John Paul MacDuffie is a professor of management and director of the Program on Vehicle and Mobility Innovation at the Mack Institute for Innovation Management at the University of Pennsylvania’s Wharton School.

Shortages of battery materials are widely seen as a brake on electric vehicles’ growth. But alternative battery chemistries that minimize or avoid the most problematic raw materials could circumvent these constraints within the next few years.

Most EV makers chose a nickel-manganese-cobalt combination for their lithium-ion batteries because it delivers the most power density, and hence longer range, for the buck. But it also relies on two problematic minerals—nickel, for which supplies are limited, and cobalt, which is both scarce and plagued by unsafe mining and exploitation of child labor. NMC batteries also can burst into flames under certain conditions.

Some EV makers such as Tesla are now embracing an older, less-expensive battery technology known as lithium-iron-phosphate, or LFP, used originally in scooters and small EVs in China. It draws entirely on cheap and abundant minerals and is less flammable. The power density of LFP is less than NMC, but that disadvantage can be overcome by advances in vehicle design.

One approach being tested eliminates the outer packaging of the batteries altogether and directly installs cells, packed in layers, into a cavity in the EV’s body chassis. This design saves weight and boosts power density and, coupled with software tweaks, could help alternative battery chemistries like LFP deliver a longer-range charge.

Eventually, solid-state batteries—with a solid electrolyte made from common minerals like glass or ceramics—could become a key EV battery technology. (So far, they can be found only in pacemakers and smartwatches.) The solid electrolyte is more chemically stable, lighter, recharges faster and has many more lifetime recharging cycles than lithium-ion batteries, which depend on heavy liquid electrolytes.

Overall, these innovations are good news for those hoping to speed up EV adoption. They also suggest that batteries, far from becoming a standardized commodity, are going to be customized as auto makers create their own vehicle designs and battery makers develop proprietary platforms.

Ms. Price is a Wall Street Journal editor in South Brunswick, N.J. Email [email protected].