To Hydrogen or Not to Hydrogen That Is the Question

Hydrogen cars are electric vehicles that use hydrogen as their fuel source. Unlike battery-electric vehicles, which store electricity in a large battery pack, hydrogen cars generate electricity on board using a fuel

cell device. In this blog post, we will explore what hydrogen cars are, how they work, their advantages and challenges, and their future potential.

What are hydrogen cars, and how do they work?

An electric motor, like other electric vehicles, powers hydrogen cars. However, hydrogen cars produce electricity using a fuel cell instead of getting electricity from a plug or a charging station. A fuel cell is a device that converts chemical energy into electrical energy by combining hydrogen and oxygen in a controlled reaction. The only byproducts of this reaction are water vapor and heat, which are emitted through the exhaust pipe.

A fuel cell comprises two electrodes (anode and cathode) separated by an electrolyte membrane. Hydrogen gas is supplied to the anode, where it splits into protons and electrons. The protons pass through the membrane to the cathode, while the electrons travel through an external circuit, creating an electric current. At the cathode, oxygen from the air is supplied, reacting with protons and electrons to form water.

A single fuel cell can only produce a small amount of electricity, so hydrogen cars use a stack of many fuel cells connected in series to power the electric motor. The electricity from the fuel cell stack can also be stored in a small battery or a capacitor for later use or for boosting performance.

Hydrogen cars store hydrogen gas in one or more high-pressure tanks, usually made of carbon fiber. Hydrogen is the lightest element in the universe but has a very low energy density by volume. Storing enough hydrogen for a long driving range takes up much space. Therefore, hydrogen tanks must be pressurized to up to 700 bar (10,000 psi) to fit more hydrogen in less space.

Hydrogen cars can be refueled at hydrogen stations, like conventional gas stations. Refueling takes about five minutes, comparable to filling up a gasoline tank. However, there are only about 500 hydrogen stations worldwide as of 2022, most located in California, Japan, Germany, and South Korea. This limits the availability and convenience of hydrogen cars for most drivers.

What are the advantages and potential of hydrogen cars?

Hydrogen cars have several advantages over other vehicles, especially regarding environmental and energy aspects. Some of these advantages are:

- Zero tailpipe emissions: Hydrogen cars emit only water vapor and heat from their exhaust pipes, which means they do not contribute to air pollution or greenhouse gas emissions at the point of use. This can improve local air quality and reduce health problems caused by smog and particulate matter.

- Renewable and abundant fuel source: Hydrogen can be produced from various sources, such as natural gas, biomass, water electrolysis, or solar and wind power. Some of these renewable sources can reduce the dependence on fossil fuels and foreign oil imports. Hydrogen is also the most abundant element in the universe, so it will never run out.

- High efficiency and performance: Fuel cells are more efficient than internal combustion engines at converting chemical energy into mechanical energy. Hydrogen cars can travel farther on less fuel than gasoline or diesel cars. Hydrogen cars also have similar performance characteristics to battery-electric vehicles, such as instant torque, smooth acceleration, and low noise.

- Flexible and scalable technology: Hydrogen cars can be adapted to different vehicle types and sizes, from passenger cars to buses and trucks. Hydrogen can also be used for other applications besides transportation, such as power generation, heating, or industrial processes. Hydrogen can also be integrated with other energy systems, such as smart grids or renewable energy sources.

What are the challenges and drawbacks of hydrogen cars?

Hydrogen cars also face several challenges and drawbacks that limit their widespread adoption and competitiveness in the market. Some of these challenges are:

- High cost: Hydrogen cars are still costly compared to conventional or battery-electric vehicles. The main reason is the high cost of fuel cells and hydrogen tanks, which require advanced materials and manufacturing processes. The cost of hydrogen fuel is also higher than gasoline or electricity per mile driven due to the low efficiency of hydrogen production and distribution.

- Limited infrastructure: As mentioned before, there are only a few hundred hydrogen stations worldwide, making it difficult for drivers to find places to refuel their hydrogen cars. Building more hydrogen stations requires significant investments from governments and private companies and regulatory and safety standards. The lack of infrastructure also affects consumer acceptance and demand for hydrogen cars, creating a chicken-and-egg problem.

- Environmental and safety concerns: Although hydrogen cars have zero tailpipe emissions, they are not necessarily carbon-neutral or environmentally friendly. The environmental impact of hydrogen cars depends on how the hydrogen is produced and transported. If hydrogen is made from fossil fuels, such as natural gas, it will still emit carbon dioxide and other pollutants during the process. If the hydrogen is made from renewable sources, such as water electrolysis, it will require much electricity, which may not be available or clean. Hydrogen is also a highly flammable and explosive gas, which poses safety risks during storage, handling, and refueling.

What is the future of hydrogen cars?

Hydrogen cars have existed for decades but have not reached mass production or commercial success. However, some car manufacturers and governments are still committed to developing and promoting hydrogen cars as part of their strategies to reduce emissions and diversify energy sources. Some examples of current and future hydrogen cars are:

- Toyota Mirai: The Toyota Mirai is one of the first and most popular hydrogen cars in the market. It was launched in 2015 and has sold about 10,000 units worldwide as of 2022. The Mirai has a fuel cell stack that produces 114 kW (153 hp) of power and a 5 kg (11 lb) hydrogen tank that gives it a range of 312 miles (502 km). The Mirai has a sleek and futuristic design with advanced features such as adaptive cruise control, lane departure alert, and blind spot monitor. The Mirai costs about $58,500 in the U.S. but is also available for lease or through incentives and subsidies in some regions.

- Hyundai Nexo: The Hyundai Nexo is another hydrogen car launched in 2018 and has sold about 1,500 units worldwide as of 2022. The Nexo has a fuel cell stack that produces 120 kW (161 hp) of power and two hydrogen tanks that hold 6.3 kg (13.9 lb) of hydrogen, giving it a range of 380 miles (612 km). The Nexo has a spacious and luxurious interior with advanced features such as remote parking assist, blind spot view monitor, and highway driving assist. The Nexo costs about $59,000 in the U.S. but is also available for lease or through incentives and subsidies in some regions.

- BMW iX5 Hydrogen: The BMW iX5 Hydrogen is a concept car unveiled in 2019 and expected to enter production in 2022. The iX5 Hydrogen is based on the BMW X5 SUV and has a fuel cell system that produces 125 kW (168 hp) of power and two hydrogen tanks that hold 6 kg (13.2 lb) of hydrogen, giving it a range of over 300 miles (483 km). The iX5 Hydrogen has a sporty, elegant design and advanced features such as adaptive suspension, a digital cockpit, and a diligent personal assistant. The iX5 Hydrogen is part of BMW's vision to offer a variety of drive technologies to suit different customer needs and preferences.

Conclusion

Hydrogen cars are electric vehicles that use hydrogen as their fuel source. They have several advantages over other vehicles, such as zero tailpipe emissions, renewable and abundant fuel sources, high efficiency and performance, and flexible and scalable technology. However, they face several challenges and drawbacks, such as high cost, limited infrastructure, and environmental and safety concerns. Hydrogen cars have yet to reach mass production or commercial success. However, some car manufacturers and governments are still developing and promoting them as part of their strategies to reduce emissions and diversify energy sources.

Hydrogen cars are an exciting and promising technology that could play a role in the future of transportation. However, there are better solutions for some situations or customers. They will have to compete with other types of vehicles, especially battery-electric vehicles, which have advantages and disadvantages. Ultimately, the future of hydrogen cars will depend on how well they can overcome their challenges, meet customer expectations, and integrate with other energy systems.