What does fuel cell technology do?

Fuel cell technology converts chemical energy stored in fuels into electricity through electrochemical reactions, typically producing electricity and heat, with only water as a byproduct when hydrogen is used. This enables quiet, scalable power for cars, buildings, and portable equipment, with strong potential to decarbonize multiple sectors as hydrogen and other fuels are produced cleanly.

How fuel cells generate electricity

In a fuel cell, fuel and an oxidizer react in an electrochemical cell separated by an electrolyte. The process creates an electric current, heat, and, for hydrogen fuel cells, water, without combustion. The technology offers high electrical efficiency and the ability to recover and reuse heat in combined heat and power systems.

Core mechanism

At the anode, fuel molecules release electrons and ions. The electrons travel through an external circuit to do work, creating electricity. The ions move through the electrolyte to the cathode, where they combine with the oxidizer (usually oxygen from air) to form heat and water. Different fuels and electrolytes determine temperature, efficiency and durability.

Leading fuel cell chemistries

There are several fuel cell families in commercial and pilot use, each optimized for different temperatures, fuels and applications. Here is a snapshot of the main types you’ll encounter.

• Proton Exchange Membrane (PEM) fuel cells — low-temperature (around 80°C), fast start-up, well suited to vehicles and portable power; typically run on hydrogen or hydrogen-rich reformates and are sensitive to fuel impurities.


• Solid Oxide Fuel Cells (SOFC) — high-temperature (600–1,000°C), high electrical efficiency with heat recovery; can run on natural gas or hydrogen; widely used for stationary power and combined heat and power (CHP).


• Phosphoric Acid Fuel Cells (PAFC) — established, moderate temperature (around 180°C); reliable for larger stationary plants; efficiency roughly 40–45% electrical, with potential CHP benefits.


• Molten Carbonate Fuel Cells (MCFC) — high-temperature (650–700°C), tolerant of fuel impurities; suitable for large-scale stationary power and industrial use; high overall efficiency with heat recovery.


• Alkaline Fuel Cells (AFC) — older design with strong performance on pure hydrogen; highly sensitive to CO2 and fuel contaminants; historically used in space missions, with niche commercial deployments.

The choice of chemistry depends on the application, fuel availability, cost and infrastructure, and researchers continue to push for longer durability and lower costs across all types.

Where fuel cells are used

Fuel cells are deployed across sectors where clean, quiet and reliable power is valuable. They are most visible in transportation, but are also expanding in stationary power, backup power and specialty markets.

• Transportation and mobility — passenger cars, buses, trucks, trains and forklifts; many fleets use PEM fuel cells for long-range, zero-emission operation with quick refueling.


• Stationary power and backup — buildings, microgrids, data centers and remote facilities; solid oxide and other high-temperature cells are common for heat-integrated power and resilience.


• Portable and specialty power — telecom backup, military and space applications; compact PEM or methanol-based fuel cells provide quiet, reliable power.


• Industrial and utility-scale power — large, centralized plants and on-site power with cogeneration using SOFC/MCFC technologies; can run on natural gas, biogas or hydrogen.

As governments push decarbonization and companies invest in hydrogen supply chains, fuel cell deployments are expanding, though fueling infrastructure and upfront costs remain key considerations.

Benefits and challenges

Key advantages

Fuel cells offer high electrical efficiency, low or zero emissions at the point of use (especially with green hydrogen), quiet operation, and scalable power—from small units to large plants. They also enable multi-source energy systems that combine fuel cells with renewables and energy storage to smooth power supply.

Key challenges

Major hurdles include building enough clean hydrogen or reformate supply, the cost and durability of fuel cell stacks, and durability and performance in diverse climates. Infrastructure gaps and the need for standardization also slow broad adoption. Materials science, catalyst improvements and economies of scale are the focus of ongoing research and policy support.

What lies ahead

Momentum is building around green hydrogen produced by electrolysis powered by renewables, making fuel cells a practical path to decarbonize transport, heat, and industry. Policy incentives, corporate investments, and partnerships are expanding the supply chain—from hydrogen production and distribution to fueling networks and manufacturing. The technology’s success will hinge on balancing cost, reliability and fuels availability while integrating with the broader energy system.

Summary

Fuel cell technology converts chemical energy into electricity through electrochemical reactions, producing clean power with water as a byproduct when using hydrogen. It offers high efficiency, quiet operation and flexibility across transport, buildings and portable power, but depends on affordable fuels and robust infrastructure. Ongoing advances in materials, manufacturing and green hydrogen production point toward broader use as part of a decarbonized energy system.

What is fuel cell technology used for?

Fuel cells can be used in a wide range of applications, providing power for applications across multiple sectors, including transportation, industrial/commercial/residential buildings, and long-term energy storage for the grid in reversible systems.

What is one major disadvantage of fuel cell technology?

Cost of Raw Materials
Precious metals such as platinum and iridium are typically required as catalysts in fuel cells and some types of water electrolyser, which means that the initial cost of fuel cells (and electrolysers) can be high. This high cost has deterred some from investing in hydrogen fuel cell technology.

How long will a fuel cell continue to produce electricity?

Fuel cells supply electricity much like batteries, but require no electrical recharging. While batteries store and release electrical energy, fuel cells produce electricity continuously as long as an external fuel source is supplied.

Does FuelCell energy have a future?

Fuel cells have the potential to be a significant part of a future clean energy landscape, especially for applications like heavy-duty transport and stationary power generation, though they still face challenges. They offer high efficiency and produce only water and heat as byproducts, making them a sustainable option for various uses, including vehicles like buses and trucks, as well as powering communities and industrial sites. However, the commercial viability and widespread adoption depend on the cost and scalability of producing "green hydrogen" and the development of the necessary infrastructure.
 
Advantages of fuel cells

• High efficiency: Fuel cells can be more energy-efficient than traditional power sources, reducing fuel consumption and emissions. 
• Zero tailpipe emissions: Fuel cells powered by hydrogen only emit water vapor and heat, which is a major advantage for reducing air and noise pollution, especially in urban areas. 
• Versatility: They can be used in a wide range of applications, from powering vehicles like cars, buses, and trucks to providing electricity for homes and data centers. 
• Grid stability: Fuel cells can provide a reliable power source for communities and help manage grid capacity, especially when integrated with renewable energy sources. 

Challenges for fuel cells

• Cost and infrastructure: The cost of fuel cells and the infrastructure required to support them, particularly for hydrogen production and refueling stations, are major hurdles to widespread adoption. 
• Hydrogen production: Currently, a significant amount of hydrogen is produced from natural gas, which is not environmentally friendly. The transition to producing "green hydrogen" through methods like electrolysis powered by renewables is necessary but requires significant investment and development. 

Where they are already used and what's next

• Commercial transport: Fuel cell technology is already being used in thousands of electric buses, particularly in China and South Korea. The focus is increasingly on applying this to larger commercial vehicles like semi-trailer trucks. 
• Material handling: Hydrogen fuel cells are already in widespread use in forklifts in warehouse operations across the US. 
• Stationary power: Fuel cells are being used by utility companies and data centers to provide reliable, clean energy and to help future-proof their energy strategies.