![]() Hydrogen gas is supplied to the anode of the fuel cell. The oxygen is typically obtained from the air, though it can be provided directly as pure oxygen. If that electricity comes from a renewable energy source such as wind or solar power, then the resulting hydrogen is a renewable, zero emission fuel. When hydrogen is produced from water electricity is used to split the water molecule. If fossil fuels are used as the original source of hydrogen there will be more by-products, such as carbon dioxide. If hydrogen is made from water the only byproduct is pure water. Most hydrogen that is produced today comes from natural gas. Fuel cells have been used in NASA space-craft since the Gemini program in the 1960’s and even today they provide electricity and drinking water for astronauts on Space Shuttle flights.īecause hydrogen does not occur naturally in the environment, hydrogen fuel must be derived from other substances that contain hydrogen such asmethanol, gasoline, natural gas, and water. For example, the heat can be used wherever a heat supply is needed. Often both of these by-products can be put to some kind of use. This makes fuel cells potentially very efficient devices with minimal environmental impact. When pure hydrogen is used as the fuel, the only by-products generated from the fuel cell are pure water and heat. Unlike batteries, the electrodes in hydrogen fuel cells are relatively stable since they act as catalysts in the release or acceptance of electrons and are not chemically changed during this process. Because battery electrodes actively participate in the conversion of chemical energy to electrical energy, over time this can have a damaging effect on the electrodes and therefore on the effectiveness of the battery. In a hydrogen fuel cell electrons are released from the hydrogen that is supplied to the anode whereas in a battery the electrons are released from the material in the anode itself. One electrode is the anode and the other is the cathode. They each have two electrodes in contact with a material that can conduct ions, called an electrolyte. Hydrogen fuel cells and batteries are both electrochemical cells. When a fuel cell is continuously supplied with hydrogen and oxygen, and the product water is removed, the fuel cell can generate electricity. A hydrogen fuel cell essentially consumes hydrogen and oxygen. This chemical energy is stored in the hydrogen that is supplied to the anode of the fuel cell. Rather than storing chemical energy inside itself, a hydrogen fuel cell receives a supply of chemical energy from the outside. ![]() This means that a battery will run down, or need recharging, when there is no longer enough stored chemical energy available to produce sufficient electricity to power the device connected to the battery. While both batteries and fuel cells convert chemical energy into electrical energy, batteries store this chemical energy inside the battery itself. Similar to a battery, a fuel cell with a supply of hydrogen and oxygen can be used to power devices that use electricity. However, there are some important differences between batteries and fuel cells. In many ways fuel cells are similar to batteries, such as those you might find in a car or in a portable electronic device like an MP3 player. But such competitiveness in the medium-term future no longer seems an unrealistic prospect, which fully justifies the growing interest and policy support for these technologies around the world.Click on the links below to learn more about hydrogen fuel cells:Ī hydrogen fuel cell converts chemical energy stored by hydrogen fuel into electricity. This review shows that challenges around cost and performance remain, and considerable improvements are still required for hydrogen to become truly competitive. This represents a step change from the situation of only five years ago. Hydrogen vehicles are available commercially in several countries, and 225 000 fuel cell home heating systems have been sold. The picture that emerges is one of qualified promise: hydrogen is well established in certain niches such as forklift trucks, while mainstream applications are now forthcoming. This paper is a comprehensive review of the potential role that hydrogen could play in the provision of electricity, heat, industry, transport and energy storage in a low-carbon energy system, and an assessment of the status of hydrogen in being able to fulfil that potential. Nonetheless, a growing body of evidence suggests these technologies form an attractive option for the deep decarbonisation of global energy systems, and that recent improvements in their cost and performance point towards economic viability as well. ![]() Hydrogen technologies have experienced cycles of excessive expectations followed by disillusion. ![]()
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