Imagine driving a car that runs clean, and emits pure water from its exhaust pipe. That’s the promise that hydrogen offers as a fuel source, and these vehicles may be commercially available sooner than you think.
Hydrogen as a Green Energy Source
Hydrogen is often considered a green energy source when it is produced using environmentally friendly methods and used in applications that produce little to no greenhouse gas emissions. This concept is often referred to as “green hydrogen.” Green hydrogen has the potential to play a significant role in the transition to a more sustainable and low-carbon energy system for several reasons:
Clean Production: Green hydrogen is produced using renewable energy sources, such as wind, solar, or hydropower, to electrolyze water (H2O) into hydrogen (H2) and oxygen (O2). This process, known as electrolysis, generates hydrogen without producing harmful emissions if the electricity used for electrolysis is sourced from renewables.
Reduced Carbon Footprint: Green hydrogen production avoids the carbon emissions associated with traditional hydrogen production methods, such as steam methane reforming (SMR) and coal gasification, which release significant amounts of carbon dioxide (CO2).
Versatile Energy Carrier: Hydrogen can be used as an energy carrier for various applications, including electricity generation, transportation, and industrial processes. It can be stored and transported relatively easily, making it a flexible energy source.
Decarbonizing Hard-to-Electrify Sectors: Hydrogen can be used in sectors that are difficult to electrify directly, such as heavy industry, long-haul transportation (e.g., trucks, ships, and trains), and certain chemical processes. By replacing fossil fuels with hydrogen in these sectors, emissions can be significantly reduced.
Energy Storage: Hydrogen can be used for energy storage, helping to balance the intermittent nature of renewable energy sources. Excess electricity generated during times of high renewable energy production can be used for electrolysis to produce hydrogen, which can then be stored and converted back into electricity when needed.
Zero Emission When Used: When green hydrogen is used in fuel cells or combustion processes, it produces no direct emissions, as the only byproduct is water vapor.
However, it’s important to note that the greenness of hydrogen depends on how it is produced. Hydrogen can also be produced using fossil fuels (gray hydrogen) or with carbon capture and storage (blue hydrogen), which reduces emissions but does not eliminate them entirely. The environmental benefits of hydrogen depend on the source of energy used for production and the overall lifecycle emissions.
Challenges associated with green hydrogen include the high cost of electrolysis technology, the need for significant renewable energy capacity to scale up production, and infrastructure development for storage and distribution.
Can Hydrogen be Produced Affordably?
The Inflation Reduction Act has earmarked clean hydrogen production in the $369 billion set aside for energy security and climate change initiatives.
As with any new industry, costs are usually high until technology improves and supply ramps up. According to an article in Newsweek, “The world’s largest producer of electrolyzers, NEL, believes green hydrogen production could reach cost parity with fossil fuels as early as 2025, and the DOE has laid out plans to reduce the cost of hydrogen to $1 per 1 kilogram within the next decade.”
How do Hydrogen-Powered Cars Work, and Who is Making them?
Hydrogen-powered cars, also known as hydrogen fuel cell vehicles (FCVs), work by using a chemical process to convert hydrogen gas (H2) into electricity to power an electric motor that drives the vehicle. Here’s how they work:
Hydrogen Storage: Hydrogen gas is stored in high-pressure tanks or sometimes in liquid form, depending on the vehicle’s design. These tanks are typically located in the vehicle’s rear or undercarriage.
Fuel Cell Stack: The heart of a hydrogen-powered car is the fuel cell stack. The stack consists of multiple individual fuel cells, each of which contains a proton-exchange membrane (PEM) or other types of fuel cell technologies, such as alkaline or solid oxide fuel cells.
Hydrogen Injection: Hydrogen from the storage tanks is delivered to the fuel cell stack. This hydrogen is typically very pure, as any impurities could damage the fuel cell.
Electrochemical Reaction: Inside the fuel cell stack, a chemical reaction takes place. Hydrogen molecules are split into protons (H+) and electrons (e-) at the anode (negative electrode) through a process called hydrogen oxidation. The protons move through the proton-exchange membrane, while the electrons are forced to travel through an external circuit, creating an electrical current.
Electricity Generation: The flow of electrons through the external circuit creates electrical power, which can be used to drive the electric motor of the vehicle. This motor provides propulsion to the wheels, allowing the car to move.
Combining with Oxygen: The protons generated at the anode travel through the proton-exchange membrane to the cathode (positive electrode), where they combine with oxygen from the air, typically supplied through an intake, to form water (H2O). This chemical reaction generates additional heat and water vapor as byproducts.
Emission: Zero Emissions: The only emissions produced by hydrogen fuel cell vehicles are water vapor and heat. There are no tailpipe emissions of harmful pollutants or greenhouse gases, making them environmentally friendly.
Energy Storage: If the vehicle has a hybrid configuration, it may also include a small battery pack for regenerative braking and temporary energy storage. This allows the vehicle to recover and store energy during braking and then release it to assist with acceleration.
One notable advantage of hydrogen fuel cell vehicles is that they offer longer driving ranges compared to many battery-electric vehicles (BEVs) due to the high energy density of hydrogen. However, there are several challenges to widespread adoption, including the limited availability of hydrogen refueling infrastructure, the energy required to produce and transport hydrogen, and the high cost of fuel cell technology.
Despite these challenges, hydrogen fuel cell vehicles are being developed and deployed by various automakers and governments, particularly in regions where hydrogen infrastructure is being developed to support their use.
Which Automakers are Developing Hydrogen-Powered Cars?
Hyundai N Vision74 (Image Source: Hyundai)
Hyndai just gave the green light for the production of the N Vision 74 Hydrogen-poweered sports care. This vehicle, designed for well-heeled sports care enthusiasts, will carry an estimated price tag of $160,000 and have superior performance, acoording to MotorTrend.
Nikola plans to start delivering hydrogen fuel cell semi trucks within the next few weeks. Companies like J.B. Hunt and AJR Trucking are lined up to take deliveries. In testing, these trucks show a range averaging over 500 miles, according a report published in Teslarati.com.
Toyota and BMW also have hydrogen fuel-cell vehicle projects underway.
