Today, the world is racing toward a future of sustainable energy. Although the final victor is unknown, hydrogen has emerged as a clear front-runner, providing numerous possibilities for energy production, distribution, and application. To solve the mystery of the title fuel cell advantages let’s start with what is fuel cell and their types and then we shall discover all about their advantages and disadvantages.
Fuel cells have been around for over 150 years and provide an endless, ecologically safe, and constantly available source of energy. So, why aren’t they used everywhere yet? Until recently, it was due to the cost. The cells were prohibitively expensive to manufacture. That is no longer the case.
What is Fuel cell?
A fuel cell is an electrochemical device that converts chemical energy into usable electrical current. Every fuel cell has two electrodes known as the anode and cathode. The electrodes are where the reactions that generate electricity take place.
Every fuel cell also has an electrolyte, which transports electrically charged particles from one electrode to the next, as well as a catalyst, which accelerates the reactions at the electrodes. Although hydrogen is the most basic fuel, fuel cells also require oxygen. One of the most appealing aspects of fuel cells is that they produce very little pollution much of the hydrogen and oxygen needed to create power eventually mix to form a harmless by-product, primarily water.
A single fuel cell produces a negligible quantity of direct current (DC) electricity. In practice, multiple fuel cells are frequently stacked together. The concepts are the same whether in a cell or a stack. After this, let’s explore fuel cell advantages and disadvantages.
4 Fuel Cell Advantages and Disadvantages
Sir William Robert Grove, a Welsh judge, inventor, and scientist, invented the first fuel cell in 1839. He created electricity and water by combining hydrogen and oxygen in the presence of an electrolyte. The innovation, later known as a fuel cell, did not generate enough electricity to be useful. So, let us go over some of the fuel cell advantages and disadvantages.
1. No recharge needed
A fuel cell does not need to be recharged. A fuel cell can replicate energy until it is supplied with fuel.
2. No Health Problems
Fuel cells are not dangerous and do not cause health problems because they do not produce smoke or smog while they operate.
Fuel cells are extremely efficient because they can transform chemical energy straight into electrical energy. In comparison to other accessible market alternatives, fuel cells are 60% more efficient.
4. Pollution Free
Fuel cells have no negative impact on air pollution. This is one of the most noticeable advantages among other fuel cell advantages. Because a fuel cell has no mechanical parts, it is completely silent, thus no noise pollution.
If hydrogen is employed as the input fuel, the only by-products noticed are water, heat, and electricity, resulting in maximum efficiency and no harmful material emission.
1. Expensive and Non Long-Lasting
Like fuel cell advantages, they have disadvantages also. Like- they are quite expensive in nature. Fuel cells have a shorter lifespan.
2. Difficult to Store
Fuel cells are difficult to store since the fuel used in the cells must be kept at a specific temperature and pressure level.
3. Unsafe and Dangerous
Hydrogen is a very flammable fuel, which raises obvious safety problems. In the air, hydrogen gas burns in concentrations ranging from 4 to 75%.
4. Difficult to extract
Despite being the most abundant element in the Universe, hydrogen does not exist on its own, thus it must be collected from water by electrolysis or isolated from carbon-based fossil fuels. Both of these approaches require a significant amount of energy to complete.
This energy can be more expensive than that obtained from hydrogen itself. Furthermore, in the absence of CCS, this extraction often necessitates the use of fossil fuels, undermining hydrogen’s ecological credentials.
What are the Various Types of Fuel Cells?
After learning about fuel cell advantages and disadvantages, let’s also learn about the various types of fuel cells. The primary distinction between fuel cells is the type of electrolyte used. This classification defines the type of:
- Electrochemical processes that occur in the cell
- The type of catalysts needed
- The temperature range at which the cell functions
- The fuel required, and other criteria.
These properties, in turn, influence the applications for which these cells are most suited. Several varieties of fuel cells are currently being developed, each with its own set of advantages, limitations, and possible applications. Learn more about the types of fuel cells below.
1. Electrolyte Membrane Polymer Fuel Cells
Polymer electrolyte membrane (PEM) fuel cells, also known as proton exchange membrane fuel cells, have a high power density and low weight and volume when compared to conventional fuel cells. The electrolyte of PEM fuel cells is a solid polymer, and the electrodes are porous carbon with a platinum or platinum alloy catalyst. They simply require hydrogen, oxygen from the air, and water to function. They are typically powered by pure hydrogen provided by storage tanks or reformers.
PEM fuel cells function at low temperatures, typically around 80°C (176°F). Low-temperature operation enables them to start quickly (with reduced warm-up time) and results in less wear on system components, resulting in greater durability. However, it necessitates the use of a noble-metal catalyst (usually platinum) to separate the hydrogen’s electrons and protons, which raises the system cost. Because the platinum catalyst is particularly sensitive to carbon monoxide poisoning, an extra reactor is required to remove carbon monoxide in the fuel gas if the hydrogen is produced from a hydrocarbon fuel. This reactor is also expensive.
PEM fuel cells are mostly employed in transportation and some stationary applications. PEM fuel cells are especially well-suited for usage in automotive applications such as automobiles, buses, and heavy-duty trucks.
2. Cells for Direct Methanol Fuel
Most fuel cells are powered by hydrogen, which can be delivered directly into the system or created within the system by reforming hydrogen-rich fuels like methanol, ethanol, and hydrocarbon fuels. However, direct methanol fuel cells (DMFCs) are fuelled by pure methanol, which is typically combined with water and delivered directly to the fuel cell anode.
Because methanol has a higher energy density than hydrogen though less than gasoline or diesel fuel. Direct methanol fuel cells avoid many of the fuel storage issues that plague some fuel cell systems. Because methanol is a liquid, like gasoline, it is also easier to transport and deliver to the public using our current infrastructure. DMFCs are frequently utilized to power portable fuel cell applications like cell phones and laptop computers.
3. Cells for Alkaline Fuel
Alkaline fuel cells (AFCs) were among the first fuel cell technologies invented, and they were the first type widely employed in the United States space program to generate electrical energy and water on-board spacecraft. The electrolyte in these fuel cells is a solution of potassium hydroxide in water, and the anode and cathode can be a number of non-precious metals.
One significant challenge for this fuel cell type is that it is prone to carbon dioxide poisoning (CO2). In fact, even trace amounts of CO2 in the air can have a significant impact on cell performance and durability due to carbonate production. Alkaline cells with liquid electrolytes can be run in a recirculating mode, which allows for electrolyte regeneration to assist lessen the impacts of carbonate production in the electrolyte but also introduces and shunt current difficulties.
Additional issues with liquid electrolyte systems include wettability, increased corrosion, and difficulties controlling differential pressures. These difficulties are addressed by alkaline membrane fuel cells (AMFCs), which are less susceptible to CO2 poisoning than liquid-electrolyte AFCs. However, CO2 continues to have an impact on performance, and the performance and durability of AMFCs fall behind that of PEMFCs.
AMFCs are being studied for applications ranging from W to kW. Tolerance to carbon dioxide, membrane conductivity and durability, higher temperature operation, water management, power density, and anode electrocatalysis are all challenges for AMFCs.
4. Cells of Phosphoric Acid
PAFCs use liquid phosphoric acid as an electrolyte (the acid is held in a Teflon-bonded silicon carbide matrix) and porous carbon electrodes with a platinum catalyst. The diagram to the right depicts the electrochemical reactions that occur in the cell.
The PAFC is regarded as a “first generation” contemporary fuel cell. It is one of the most developed cell kinds and the first to be commercialized. Although this type of fuel cell is normally used to generate stationary power, some PAFCs have been used to power large vehicles such as city buses.
PAFCs are more resistant to impurities in reformed fossil fuels than PEM cells, which are easily “poisoned” by carbon monoxide because carbon monoxide binds to the platinum catalyst at the anode, reducing the fuel cell’s efficiency. PAFCs are more than 85% efficient when used to generate both electricity and heat, but they are less efficient when used to generate only electricity (37%-42%).
The efficiency of PAFCs is only somewhat higher than that of combustion-based power plants, which normally run at around 33% efficiency. Given the same weight and volume, PAFCs are likewise less powerful than other fuel cells. Thus, these fuel cells are typically large and hefty. PACs are also costly. They require substantially greater platinum catalyst loadings than other forms of fuel cells, which raises the cost.
5. Fuel Cells for Molten Carbonate
Molten carbonate fuel cells (MCFCs) are being developed for natural gas and coal-fired power stations, as well as for electrical utility, industrial, and military uses. MCFCs are high-temperature fuel cells that use an electrolyte made up of molten carbonate salts floating in a porous, chemically inert ceramic lithium aluminum oxide matrix. Non-precious metals can be employed as catalysts at the anode and cathode since they work at high temperatures of 650°C (approximately 1,200°F).
Another reason MCFCs offer significant cost savings over phosphoric acid fuel cells is improved efficiency. When combined with a turbine, molten carbonate fuel cells can achieve efficiencies approaching 65%, which is significantly greater than the 37%-42% efficiencies of a phosphoric acid fuel cell operation. Overall fuel efficiency can exceed 85% when waste heat is recovered and utilized.
MCFCs do not require an external reformer to convert natural gas and biogas to hydrogen. Because MCFCs operate at high temperatures, methane and other light hydrocarbons in these fuels are transformed to hydrogen within the fuel cell itself via a process known as internal reforming, which also saves money.
The fundamental downside of existing MCFC technology is its short lifespan. The high operating temperatures of these cells, along with the caustic electrolyte employed, hasten component breakdown and corrosion, reducing cell life. Scientists are currently investigating corrosion-resistant materials for components, as well as fuel cell designs that can double cell life from the current 40,000 hours (five years) without compromising performance.
6. Cells for Solid Oxide Fuel
In solid oxide fuel cells (SOFCs), the electrolyte is a dense, non-porous ceramic. SOFCs convert fuel to electricity at a rate of about 60% efficiency. Overall fuel use efficiency could exceed 85% in systems intended to capture and utilize the system’s waste heat (co-generation).
SOFCs function at extremely high temperatures, up to 1,000°C (1,830°F). High-temperature operation eliminates the requirement for a precious-metal catalyst, lowering costs. It also enables SOFCs to reform fuels internally, allowing them to use a wider range of fuels and lowering the expense of adding a reformer to the system.
SOFCs are also the most sulfur-resistant fuel cell kind, able to withstand orders of magnitude more sulfur than other cell types. Furthermore, they are not harmed by carbon monoxide, which can even be used as fuel. This characteristic enables SOFCs to use natural gas, biogas, and coal-derived gases. There are drawbacks to operating at high temperatures.
It causes a delayed starter and necessitates extensive thermal shielding to preserve heat and protect employees, which is fine for utility purposes but not for transportation. Because of the high operating temperatures, materials must meet severe durability standards. The primary technical difficulty for this technology is the development of low-cost materials with high endurance at cell operating temperatures.
Scientists are now investigating the possibility of building lower-temperature SOFCs that operate at or below 700°C, have fewer durability issues, and are less expensive. Lower-temperature SOFCs have not yet equaled the performance of higher-temperature systems, and stack materials for this lower-temperature range are still being developed.
7. Reversible Fuel Cells
Reversible fuel cells, like conventional fuel cells, create electricity from hydrogen and oxygen while also producing heat and water as by-products. Reversible fuel cell systems, on the other hand, can use electricity from solar, wind, or other sources to split water into oxygen and hydrogen fuel via a process known as electrolysis.
Reversible fuel cells can produce electricity when it is required, but during periods of high power output from other technologies (for example, when high winds result in an excess of available wind power), reversible fuel cells can store the excess energy in the form of hydrogen. This energy storage capability has the potential to be a game changer for intermittent renewable energy technology. After this, let’s learn about the working principle of fuel cells.
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What is the Working Principle of Fuel Cell?
After learning about fuel cell advantages, you should also learn about the working principle of fuel cells. A fuel cell is made up of two electrodes, an anode and a cathode separated by an electrolyte membrane. Hydrogen, methane, ethane, ethanol, and other organic fuels can be utilized in a fuel cell to generate electricity. These fuels undergo incomplete combustion and emit heat as a by-product. Most of these reactions are redox in nature and create water and carbon dioxide as by-products.
The transport of electrons in redox reactions results in the conversion of chemical energy to electrical energy. Between the electrodes lies an electrolyte substance. Fuel is delivered to each electrode separately. Assume that in a fuel cell, hydrogen is delivered to the anode, and air is fed to the cathode. In this case, the catalyst on the anode side of the cell tends to break down the hydrogen molecules into smaller particles, such as protons and electrons.
Both elements attempt to travel toward the cathode via distinct routes. The electrons follow an external channel to the cathode, providing current, whereas the protons pass through the electrolyte membrane to the cathode, where they react with oxygen molecules and electrons to form water and heat as by-products.
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List Some Fuel Cell Applications
Let’s look at ten uses for hydrogen fuel cells, some of which you might not be aware of!
1. Warehouse Management: Several large warehousing and distribution organizations are turning to hydrogen fuel cells to power clean trucks, forklifts, pallet jacks, and other equipment.
2. International Distribution: Fuel cells have the range and power needed for long-distance haulage and local distribution. Nikola, Hyundai, Toyota, Kenworth, and UPS are already manufacturing hydrogen-powered semi-trucks and vans.
3. Buses: Hydrogen power is being studied for use in different modes of public transportation, including hydrogen fuel cell buses. Several large cities have experimented with hydrogen-powered buses, including Chicago, Vancouver, London, and Beijing.
4. Trains: Hydrogen fuel cell trains have now arrived in Germany, and more types are projected to arrive in the United Kingdom, France, Italy, Japan, South Korea, and the United States over the next five years.
5. Individual Vehicles: Nine major automakers are working on hydrogen fuel cell electric vehicles (HFCEVs) for personal use. Toyota Mirai, Honda Clarity, Hyundai Nexo, and BMW I Hydrogen Next are among the notable models.
6. Airplanes: Several experimental projects, including the Pathfinder and Helios prototypes, have investigated the use of hydrogen fuel cells in aerospace. These long-distance unmanned vehicles used a hybrid system with hydrogen fuel cells that were powered by solar arrays, enabling theoretically limitless day and night continuous flight.
7. Generation of Backup Power: Stationary fuel cells are utilized in uninterruptible power supply (UPS) systems where continuous uptime is important. Hospitals and data centers are increasingly turning to hydrogen for uninterruptible power supply. Microsoft recently made news for a successful test of its new hydrogen backup generators, which allowed one data center’s server to function on nothing but hydrogen for two days.
8. Generation of Mobile Power: Hydrogen provides numerous choices for mobile power generation. NASA, in fact, produced some of the first hydrogen fuel cells to power rockets and space shuttles in space.
9. Unmanned Aerial Vehicles (UAVs): Many innovative applications of UAVs (i.e., drones), ranging from package delivery to search and rescue missions, are severely hampered by the power and range provided by standard batteries. Both the military and private businesses intend to address these issues with hydrogen fuel cells, which have up to three times the range of battery-powered devices. Fuel cells provide a greater energy-to-mass ratio and can be recharged in a matter of minutes.
10. Boats and Submarines: Hydrogen fuel cells are being used in a variety of marine applications. Some boats, such as the Energy Observer, even create their own hydrogen for a fuel cell system using onboard solar panels and wind turbines. Hydrogen fuel cells provide an alternative to nuclear power for military stealth submarines such as the German Type 212, with great range, silent cruising, and little exhaust heat.
Fuel cells are a promising replacement for today’s automobile fuels. Although certain parts of the technology, such as effective onboard storage, require more development, there is no reason why fuel cells cannot become as convenient and appealing a transportation fuel as diesel or gasoline is today. I hope through this article it was easy to understand fuel cell advantages and disadvantages. Please share your queries in the comment section.
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