A hydrogen fuel cell is a device that generates electricity through an electrochemical reaction. When hydrogen and oxygen are combined in a fuel cell, it produces electricity, heat, and water. Unlike traditional power sources, this electrochemical reaction does not rely on combustion. Hydrogen fuel cells produce no emissions other than water, making them a clean and efficient source of energy.
Hydrogen is the most abundant element in the universe; it is a colorless, odorless gas. In its natural state, hydrogen is usually bonded with other elements, such as oxygen in water (H2O) or carbon in hydrocarbons. Hydrogen has many unique properties making it an attractive element for a wide range of applications.
One of the most critical properties of hydrogen is its high energy content per unit of weight, which makes it an ideal fuel source. When hydrogen is burned or reacted with oxygen in a fuel cell, it produces water vapor and releases a large amount of energy.
How Do Hydrogen Fuel Cells Work
Much like batteries, when fuel cells are connected to an electrical circuit, hydrogen ions move from the cathode to the anode, converting chemical energy into electrical energy.
Inside the fuel cell, hydrogen is fed into the anode (negative electrode), while oxygen is fed into the cathode (positive electrode), separated by an electrolyte membrane. The hydrogen atoms are then split into protons and electrons, with the electrons passing through an external circuit to generate electricity. At the same time, the protons migrate through the electrolyte membrane to the cathode, where they combine with oxygen and electrons to form water vapor.
Advantages and Challenges of Hydrogen Fuel Cells
Hydrogen fuel cells have emerged as a promising clean energy technology with a wide range of applications. They offer several advantages over traditional power sources that use fossil fuels, including quiet and efficient operation and zero-emission byproducts of heat and water. In addition to powering small portable devices and large industrial machines, fuel cells can provide power for transportation, industrial and commercial buildings, and long-term energy storage for the grid in reversible systems.
As a versatile energy source, hydrogen fuel cells have the potential to revolutionize multiple sectors and play a crucial role in the transition to a sustainable energy future.
Benefits at a Glance
- Produces Zero Emissions: Fuel cells are an incredibly clean source of energy.
- Highly efficient: Fuel cells achieve an energy conversion rate of up to 60%, which is far more efficient than traditional energy sources.
- Hydrogen is the Most Abundant Element in the Universe: The supply of hydrogen fuel is virtually limitless, making it one of the top renewable sources of energy.
- Lightweight: This makes fuel cells ideal for use in applications where weight is a concern, such as airplanes or space shuttles.
- Scalable: Individual fuel cells can be joined with one another to form stacks. In turn, these stacks can be combined into larger systems.
- Low Operational Costs: Hydrogen fuel has a longer lifespan than traditional batteries and requires less maintenance, and can be produced from a variety of feedstocks, including natural gas, biomass, and renewable energy sources such as wind and solar power.
Key challenges in the fuel cell industry include cost, performance and durability. However,
the U.S. Department of Energy (DOE) is working closely with its national laboratories, universities, and industry partners to overcome critical technical barriers (source). These hurdles need to be addressed for widespread adoption of this promising technology.
Challenges at a Glance
- Expensive to manufacture due the high cost of catalysts (platinum)
- Lack of infrastructure to support the distribution of hydrogen
- A lot of technology in the prototype stage and not yet validated (source)
Although there are challenges to overcome, hydrogen fuel cells hold tremendous promise as a clean, efficient, and versatile source of energy that produces zero emissions other than water. With support from the DOE, continued investment and advancements in development, hydrogen fuel cells could play a significant role in meeting our energy needs in the future.