Transition to Net Zero: No Single Silver Bullet
by Julie Keenahan
A Path to Zero Carbon
Carbon-free power is within sight. Significant progress has been made toward lowering the cost of wind and solar generation, and new low and zero-carbon generation solutions are being deployed every day. However, forecasts for renewables penetration in transportation and heating remain dismally low. Considering that transportation alone contributes 14% of global greenhouse gas emissions, the planet still has a long way to go in transitioning to clean energy.
In response to this challenge, “electrify everything” has become a rallying point for climate activists and thought leaders around the world. As grid emissions intensity continues to decline, electrifying all of global heat and transportation could slash net 2050 emissions by 126 GtCO2, while increasing generation capacity needs to over 30% the forecasted levels.
Meeting this additional power demand, at least 3,950 TWh of which will come from electric vehicles alone, is a challenge on its own. But another is that for many applications, electricity is an inferior source of energy. Supply must match demand, instantaneously. This essential law is inconsistent with how we use much of our energy today.
Power has Limits
Combustion fuels, like oil and gas, have two essential advantages over electricity: portability and storability. These characteristics enable the flexibility that is essential for transportation applications and provide resilience and redundancy in climates with severe or very cold weather.
For example, while electric heat pumps are desirable options for heating and cooling in mild climates, they are less efficient and economical in cold environments, and lack the redundancy that fuel-powered furnaces provide. Imagine that you are a senior living alone in upstate New York. A blizzard hits, and the power goes out. Adding to the issue, battery efficiency and electric vehicle range also decline significantly when the mercury dips below zero. These kinds of energy consumers can’t rely on instantaneous power to save them – energy must be available, stored on site.
Without enough distributed energy storage options, grid reliability becomes essential. Just as utilities are working to build resilience against intense storms from climate change, cyberattacks, and solar flares, climate hawks are calling for total energy dependence on electricity. Without careful planning, this could leave millions of people vulnerable to energy insecurity.
The Challenge of Storing Electrons
Storing electrons in batteries is getting cheaper every year. However, batteries are currently built with rare earth metals like lithium and cobalt, which have supply chain transparency and sustainability issues. Wind and solar assets themselves also require rare materials that are in limited supply. Many of these supply chains are controlled by China, presenting a risk to other nations hoping to develop affordable clean technology. Will mining of these materials meet the world’s demand for the renewable generation and battery capacity we need? Just electrifying the UK’s vehicle fleet by 2035 could require twice the world’s current cobalt production. Extrapolating that to the globe, and piling on heating and backup battery power for many homes and businesses seems nearly impossible. And we haven’t even discussed air travel, commercial shipping, or industrial energy use.
Renewable electrification of much of the world’s energy is possible and desirable, but storage and resilience present challenges. The advantages of combustion fuels are hard to ignore, especially for applications in transportation, cold climates, and vulnerable grids. To transition, smarter, greener fuel alternatives must be prioritized with the same enthusiasm as electrification.
Opportunities for fuel alternatives abound. Rather than stranding or wasting existing infrastructure and technological assets, we could use them to our advantage to implement renewable fuels. Much of the U.S. has existing natural gas infrastructure that could help deliver alternative fuels like biogas from landfills or syngas (a synthetic gas fuel formed from carbon monoxide and hydrogen) from captured CO2 to homes, businesses, and industrial customers. Biofuels like ethanol can be swapped into internal combustion engines, reducing lifecycle emissions by 34% (although depending on how they are produced, land use and deforestation impacts can counter these improvements). Excess peaks in renewable power generation could be “stored” by powering hydrogen or other alternative fuel production when grid demand can’t ramp up fast enough.
There are some bright spots where progress is being made. Japan is already committing to hydrogen fuel to fill gaps in its energy demands. Shell is developing biofuels for trucking, hydrogen for commercial applications, and municipal solid waste for jet fuel. Still, greater investments and public awareness campaigns must be made to scale critical fuel alternative technologies quickly enough to meet our climate goals. Vehicle electrification and renewable power are exciting, but they won’t solve all of society’s clean energy needs. As the world transitions to clean energy, all strategies must be encouraged.