Why Hydrogen May Be Renewable Energy's Best Bet
Opinion/Analysis
Legend has it that when Henry Ford was asked if he developed the Model T in response to customer demands, he famously responded: “If I had asked people what they wanted, they would have said faster horses.” This quote has been used for 100 years to describe the paradox between what customers perceive they want based on their own life experiences vs. what could be possible based on current science and technology.
Today’s energy transformation is caught in a similar paradox. The “faster horses” offered by cheap natural gas and oil need to be replaced with technology that can minimize CO2 emissions and mitigate climate change.
The Model T, and the assembly line used to produce it, profoundly disrupted the transportation sector. While the assembly line continues to be widely used across multiple sectors, that car’s impact was short-lived and was soon replaced by better options.
Wind, Solar Capacity Issues
Similarly, many policy makers, anxious to decarbonize the energy sector, have created a vast array of policy and financial incentives to deploy wind and solar technologies. While their efforts offer hope for achieving emission reductions, they have also created challenges to existing energy systems because intermittency associated with daily and seasonal fluctuations in sunlight and wind availability can affect power grid stability. The grid promises to be further challenged by expansion of the electric vehicle market and the increases in power required for charging.
Until better options are found to address the energy supply and demand fluctuations associated with renewable energy, more widespread adoption will likely struggle.
At least 32 utilities are currently aiming to be carbon-free by 2050 and 68% of customer accounts in the U.S. are now served by utilities with CO2 emission reduction goals. In order for wind and solar power to fully replace fossil fuel and nuclear plants, they would need to be constructed with several times the capacity of the more dependable fossil fuel and nuclear power sources. Considerable energy storage capacity would also be required to store surplus power generated during periods of high wind and solar availability, then release the power to the grid during times when renewables are less productive.
Lithium-Ion’s Limits
Energy storage can be accomplished through multiple technologies, including chemical storage in fuels and batteries; thermal storage in heated or cooled materials; mechanical storage in springs, flywheels, etc.; electrical storage in capacitors; and hydrologic storage in reservoirs. Hydrologic storage is currently the most prevalent source of energy storage in the U.S,. with 1,460 conventional reservoirs where water is pumped uphill into a reservoir, followed by energy recovery, when the water is allowed to flow downhill. However, lithium-ion batteries are rapidly becoming the innovation of choice for both grid storage and electric vehicles.
Battery technology has been successfully applied to limited grid applications such as short-term (a few hours) substitution for peaking power plants (usually powered by natural gas) that are used sporadically to address unusually high power demand. However, implementation of batteries at the scale required for grid stability is not close to being economically feasible. MIT estimates $2.5 trillion in investment would be required to provide adequate battery storage to ensure U.S. grid stability.
Battery technology is also the predominant source of energy storage in electric vehicles (BEVs). BEV sales currently comprise about 2.6% of global car sales but are increasing rapidly, registering a 40% increase in 2019. However, BEV performance continues to lag conventional vehicles powered by fossil fuels in a number of aspects: cost, weight, range, charging time and performance in cold weather. Additionally, spent batteries often generate considerable waste because of limited recycling capacity. The supply chain associated with lithium ion battery production is also a concern.
Better battery technologies will certainly emerge in the years to come. However, improvements will likely be incremental because the required advances in chemistry, physics, and material science do not usually occur at the same rates as say, advances in information technology. As a recent analysis by MIT points out: “Countless breakthroughs have been announced over the last decade. ime and time again these advances have failed to translate into commercial batteries with anything like the promised improvements in cost and energy storage.”
The Hydrogen Option
Hydrogen has the potential to play a vital role in meeting the energy storage needs required to slash CO2 emissions. It is the most plentiful element in the universe and its capability as an effective energy carrier has been well-understood for decades. Significant planning and investment took place in the early 2000s, but hydrogen technologies failed to deliver satisfactory performance and financial returns.
However, technology developers have continued to work to address shortfalls and considerable progress has been made. Technologies that produce, store, transport and utilize hydrogen have now advanced to a point where hydrogen is emerging as a feasible option for applications in grid storage, transportation, metals refining, and heat for buildings and industrial applications.
Hydrogen can be produced and used without toxic pollution or CO2 emissions. It burns clean when mixed with oxygen from the atmosphere and can be used as a source of heat or to power an internal combustion engine. Hydrogen can also be fed into a fuel-cell device that converts hydrogen’s chemical energy into electricity. In either case, the only emission produced is water vapor. When hydrogen fuel cells are used to power an electric motor, the system is more than twice as efficient as conventional internal combustion engines.
Hydrogen rarely exists in isolation but is amassed in enormous quantities in water, hydrocarbons, and biomass. Efficient extraction of hydrogen from these compounds is critical for wide scale deployment. Currently, about 95% of hydrogen is produced by splitting it from natural gas through a process called “steam-reforming.” Hydrogen produced in this manner is referred to as “gray” and is generally not considered an effective climate solution because it gives off CO2 as a byproduct. However, it is possible to capture and sequester the CO2 to produce “blue” hydrogen at an additional cost of about 30%. The oil and gas sector, in particular Shell, BP, and Repsol, are interested in the blue hydrogen approach because it could help preserve the value of their natural gas assets.
'The Most Equitable of All Fuels'
Hydrogen is the most equitable of all fuels because it can be produced anywhere there is access to electricity and water using a process called electrolysis, where an electric current is used to split hydrogen from oxygen. If the electricity comes from renewable sources, the hydrogen fuel is considered to be renewable or “green” because it is produced without CO2 emissions. Electrolysis is energy-intensive and has only recently been considered feasible as the cost of renewable power has declined and electrolysis technology has improved. Nuclear power can also provide the energy for electrolysis to split water without CO2 emissions. U.S. utilities Exelon, FirstEnergy, Xcel Energy, and Arizona Public Service have all committed to commencing small-scale hydrogen production at nuclear plants.
Fuel Cell Electric Vehicles (FCEVs) are becoming increasingly popular in the transportation sector, particularly in large-scale applications with high utilization rates such as busing, trucking, rail and maritime. FCEVs are powered by electric drive trains similar to BEVs, with
the primary difference being FCEVs store energy primarily in tanks filled with hydrogen instead of large, heavy, battery packs. The much lighter weight associated with hydrogen fuel storage offers considerable advantages as vehicles, payloads and journeys are scaled up. Additionally, FCEVs offer much faster fueling, superior range, and better cold-weather performance than BEVs. Many product developers also see considerable opportunities for future innovation that can improve performance and reduce costs.
Despite its many advantages, hydrogen still faces a variety of challenges preventing widescale deployment, such as a lack of infrastructure for production, transportation, storage and fueling. Large-scale storage requires massive tanks made from special materials or injection into geologic resources such as caverns or saline aquifers. Hydrogen fuel tanks on vehicles store the fuel at very high pressure, and the fuel is expensive. Gray hydrogen made from fossil fuels currently costs between $0.9-3.2/kg to produce, whereas green hydrogen can cost around $3.0-7.5/kg (cost is heavily dependent on electricity costs). For comparison purposes, a kg of hydrogen contains about the same amount of energy as a gallon of gasoline. However, a large portion of the higher cost can be offset by the fact that FCEV drive trains are more than twice as efficient and require less maintenance than internal combustion drive trains. Recent analyses performed MIT and Wood Mackenzie predict the cost of green hydrogen will decline 30% by 2030.
A recently released report from the Hydrogen Council, a global CEO-led initiative of 92 leading energy, transport, industry, and investment companies, estimates over 30 countries have released hydrogen roadmaps and governments worldwide have committed public funding for hydrogen initiatives. At least 228 large-scale projects have been announced along the value chain, with 85 percent located in Europe, Asia, and Australia. These include large-scale industrial usage, transport applications, infrastructure, and giga-scale production projects. If all announced projects come to fruition, total investments will reach more than $300 billion by 2030.
In the U.S. California leads the way in both hydrogen infrastructure and FCEV deployment with about 8,500 vehicles and 42 fueling stations, with 15 fueling stations under development. The rest of the U.S. has committed relatively few resources to hydrogen technology, but this is about to change. Colorado has formed a hydrogen network focused on deploying hydrogen technology. A Midwest Hydrogen Partnership has been formed to address the challenges, barriers, and opportunities that can enable a prosperous Midwestern hydrogen economy. The USDOE recently committed $64 million in Fiscal Year 2020 funding for 18 projects that will support their H2@Scale vision for affordable hydrogen production, storage, distribution, and use.
While Henry Ford’s Model T did not have staying power, the assembly line innovations that produced it have transformed industrial production forever. Similar to the assembly line, hydrogen technologies offer the potential to change the way we produce, store, and use energy forever by enabling more widespread use of carbon free energy sources. The only true obstacle that can prevent this disruption from happening is the strength of our collective will.
Dr. Tim Lindsey is a Senior Advisor to the University of Illinois Smart Energy Design Assistance Center and CEO of Highlander Innovation Inc.
