Hydrogen Fueled Cars & Trucks Are Part of the Renewable Fuel Future
Clean Hydrogen Internal Combustion Engines for a Carbon-Neutral Future
The race to develop a carbon-neutral vehicle has spawned a variety of alternative forms of power sources for the consumer to consider. We recently published an article about the addition of synthetic fuels for existing gasoline-powered vehicles to the market, and how it increases the intensity of competition for automakers to contend with when designing new clean-running vehicles. Now, with the addition of the hydrogen-fueled internal combustion engine to the carbon-neutral future, the competition among low and zero-emission carbon-neutral vehicles continues to intensify.
The goal remains clear and uniform: develop a low-emission or carbon-free fuel or vehicle that is user friendly, can be serviced by existing infrastructure and be priced within the budgetary realm of the average driver. As we’ll explore in this article, hydrogen fuel for the internal combustion engine might just be an answer.
Hydrogen Fuel Engine Feasibility Successfully Tested by the Society of Automotive Engineers (SAE)
The Society of Automotive Engineers (SAE) studied the feasibility of the hydrogen-fueled internal combustion engine in a controlled experiment using a high-efficiency singe-cylinder gasoline engine as the test platform. The engine was fitted with a direct-injection hydrogen fueling system, and a non-platinum cold spark plug. A cold spark plug is a standard plug designed for high-heat dispersal. The point of the test was to prove that the advantages of the already-existing hydrocarbon fuel engines would remain intact when burning hydrogen as a fuel source1.
The result of the SAE’s thorough testing showed that the highest efficiency of operation of 47% was obtained through a lean mixture and an early injection of the hydrogen during the intake cycle. This is on-par with a maximum efficiency modern gasoline engine, and more efficient than most vehicles currently on the road2.
Pre-ignition during the compression cycle, also known as Ping, has historically been solved in internal compression engines by using higher octane fuel and proper adjustment of the ignition timing. The challenge of pre-ignition in hydrogen combustion was successfully limited by adjusting the injection timing and the phasing of the camshaft lobes2.
Toyota’s Hydrogen Internal Combustion Engine Milestone
While the SAE conducted a feasibility study on the hydrogen-fueled internal combustion engine1, the Toyota Motor Corporation was already at work with the same development. Toyota commissioned the Yamaha Motor Company to design a hydrogen-fueled internal combustion V-8 engine based on the Toyota Lexus RC-F coupe production motor. Using this established design, Yamaha modified the gasoline engine to use hydrogen fuel. The successful result was revealed to the press and public when the partnership demonstrated its Hydrogen V-8 engine in 2022.
Toyota, Yamaha and the SAE have shown that the best aspects of the internal combustion engine that we all enjoy - autonomy, pre-existing and proven technology, lifetime controlled cost, and existing maintenance and marketing -- can be retained within the established framework of internal combustion powerplants1,2.
Hydrogen Fuel Shares the Same Challenges as EV and Renewable Synthetic Gasoline
As expected with any advanced technology, hydrogen fuel is undergoing similar developmental pressures as the Electric Vehicle and Renewable Synthetic Gasoline market. The supply of EV resources, scalability of processes and infrastructure needed for the fuel to be produced, and the cost of new technology needs to be brought under control for the public to embrace an affordable product. All of the contenders in the alternative fuel market face various combinations of this reality. Three of the big factors are access, scalability of production, and distribution of power sources.
Scalability of Alternative Power Production
The scalability of both lithium supply chains as well as the build-out of renewable synthetic gasoline or hydrogen production are current limiting factors on the growth of the non-fossil fuel vehicle market.
Increasing the production of EV batteries is a big challenge, as the lithium needed to build these high-capacity batteries is an expensive commodity in limited supply. This is due to a significant portion of the known natural lithium reserves being located in areas that represent significant geopolitical hurdles to access. The cost and environmental impact of lithium mining is also an issue.
Hydrogen and Renewable Synthetic Gasoline do not require mining, produce little environmental waste, and have little to no restrictions from political boundaries. However, they do rely on renewable energy to keep the fuel production cycle green. Continued build-out of solar, wave, wind and hydro-electric sources must continue, and maintenance and modernization of nuclear power is a must.
The material issues might be different, but they all present significant challenges for all alternative fuel types currently under development.
Alternative Fuel Distribution & Renewal
Distribution is the other big factor, and this is where renewable synthetic gasoline and hydrogen currently have the infrastructural advantage over the patchwork availability of EV charging stations. Synthetic gasoline and hydrogen fuel are both power sources being developed with major investments by fossil-fuel companies looking to offer the cleanest economic and environmental solution. The advantage will be budgets and distribution networks. Fossil fuel companies already own a vast network of real estate holdings in the form of refineries, distribution hubs and a nationwide chain of refueling stations.
For hydrogen fuel, the customer-facing service stations will need to be fitted with purpose-designed hydrogen fueling equipment and storage tanks. However, for renewable synthetic gasoline like Coryton’s Advanced Fuel, the current service station infrastructure can be used as-is3.
For electric vehicles, the charging apparatus is a mature design already in use. The issue is one of building out the required number of charging stations across the nation to meet traveler demand. While the charging system is a fully-tested and reliable commercial device, recharging takes much longer to accomplish compared with refilling a fuel tank. This may not be suitable for long-distance driving where time schedules are a factor. Hydrogen or synthetic fuel tanks can be refilled in a matter of minutes.
There are advantages and disadvantages in both systems, and the suitability of each will depend on consumer need, cost and geographic distribution. This is why EVs, renewable synthetic fuels, hydrogen ICE and fuel cells will most likely be co-existing power solutions.
Hydrogen Can Be Used in Both Internal Combustion Engines and Fuel Cell Power
Hydrogen holds a big advantage: it has the additional benefit of being a fuel for two types of vehicles. As demonstrated earlier, hydrogen can be in an internal combustion engine, where the hydrogen in directly injected under high pressure, and then consumed to produce power. It can also be used as the fuel for the hydrogen fuel-cell powered electric vehicle. In the case of the latter, Toyota already has a production vehicle that uses this technology. The Toyota Mirai is already on the market in the UK, Denmark, Germany, Belgium, and Norway, and is also now sold & serviced in California. Utilizing a hydrogen fuel cell stack (FCS), Mirai is a ZEV; a Zero Emission Vehicle4. Hyundai has also joined the hydrogen fuel cell revolution by rolling out its first hydrogen fuel-cell car for sale or lease to the public5. This FCS model is the Hyundai Nexo, and it is now available in California.
A fuel with multiple uses can serve two types of vehicles at one service station. This is a major advantage for hydrogen producers, as it can power two very different systems that use the same basic fuel. For hydrogen fuel production, this could create high efficiency at large scale, as the same infrastructure could serve both types of vehicles. The hydrogen fuel cell stack subject we will explore in our next article about the carbon-neutral future.
Why Competing Carbon-Free Fuels Matter to Everyone
The competition is high in the multi-trillion-dollar global automotive market6. With Lithium-battery powered cars, renewable synthetic gasoline for current gas-powered cars, hydrogen fuel cells and hydrogen direct-injected internal combustion engines, and hybrids of many kinds, the future of transportation will ultimately be about consumer choice.
For the foreseeable future, there will not be a one-for-one direct replacement of fossil fuels. A formula of technology, distribution, cleanliness, and cost will determine the best power source for the vehicle buyer. It is already apparent that manufacturers know this and are developing technology at breakneck speed to capture as much market share as possible.
For aspiring automotive & diesel technicians, this is a renaissance period for transportation. Renewable synthetic fuel can extend the lives of existing gasoline & diesel powered vehicles, and also fuel hybrid vehicles. But other vehicles are also on the horizon, as exemplified by the Toyota Mirai. The Mirai is being serviced in California Toyota dealerships alongside gasoline powered vehicles. A technician who is knowledgeable about both types of powertrains would be a valuable asset to the dealership and consumer. Technicians, stay informed of industry trends and update your skill set – this can keep your services in high demand.
--- References ---
1 Technical Paper “Experimental and Numerical Investigation on Hydrogen Internal Combustion Engine”, number 2021-24-0060, published on September 5, 2021 at https://www.sae.org/publications/technical-papers/content/2021-24-0060/ Retrieved August 30, 2023.
2 “Engine Efficiency” subject matter on Wikipedia, sub-section to reference: Gasoline (Petrol) Engines found at https://en.wikipedia.org/wiki/Engine_efficiency Retrieved August 30, 2023.
3 From the Coryton Corporate Website at https://coryton.com/. Retrieved on October 19, 2023.
4 From the Toyota Motor Company website at https://www.toyota.com/mirai/. Retrieved on October 19, 2023.
5 From Hyundai USA website at https://www.hyundaiusa.com/us/en/vehicles/nexo. Retrieved on December 28, 2023.
6 From LinkedIn Pulse Reports at https://www.linkedin.com/pulse/automotive-market-size-growth-2023-2030-report. Published August 23, 2023. Retrieved on Retrieved on October 19, 2023.