![]() ![]() In 1932, English engineer Francis Thomas Bacon successfully developed a 5 kW stationary fuel cell. The Brits who bolstered the Moon landings, BBC Archives. This was used by NASA to power lights, air-conditioning and communications. In 1932, Francis Thomas Bacon invented a fuel cell which derived power from hydrogen and oxygen. The energy efficiency of a fuel cell is generally between 40 and 60% however, if waste heat is captured in a cogeneration scheme, efficiencies of up to 85% can be obtained. PEMFC cells generally produce less nitrogen oxides than SOFC cells: they operate at lower temperatures, use hydrogen as fuel, and limit the diffusion of nitrogen into the anode via the proton exchange membrane which forms NOx. In addition to electricity, fuel cells produce water vapor, heat and, depending on the fuel source, very small amounts of nitrogen dioxide and other emissions. Individual fuel cells produce relatively small electrical potentials, about 0.7 volts, so cells are "stacked", or placed in series, to create sufficient voltage to meet an application's requirements. A related technology is flow batteries, in which the fuel can be regenerated by recharging. Fuel cells are classified by the type of electrolyte they use and by the difference in startup time ranging from 1 second for proton-exchange membrane fuel cells (PEM fuel cells, or PEMFC) to 10 minutes for solid oxide fuel cells (SOFC). At the cathode, another catalyst causes ions, electrons, and oxygen to react, forming water and possibly other products. ![]() At the same time, electrons flow from the anode to the cathode through an external circuit, producing direct current electricity. The ions move from the anode to the cathode through the electrolyte. At the anode, a catalyst causes the fuel to undergo oxidation reactions that generate ions (often positively charged hydrogen ions) and electrons. There are many types of fuel cells, but they all consist of an anode, a cathode, and an electrolyte that allows ions, often positively charged hydrogen ions (protons), to move between the two sides of the fuel cell. They are also used to power fuel cell vehicles, including forklifts, automobiles, buses, trains, boats, motorcycles, and submarines. Fuel cells are used for primary and backup power for commercial, industrial and residential buildings and in remote or inaccessible areas. Since then, fuel cells have been used in many other applications. The alkaline fuel cell, also known as the Bacon fuel cell after its inventor, has been used in NASA space programs since the mid-1960s to generate power for satellites and space capsules. The first commercial use of fuel cells came almost a century later following the invention of the hydrogen–oxygen fuel cell by Francis Thomas Bacon in 1932. The first fuel cells were invented by Sir William Grove in 1838. Fuel cells can produce electricity continuously for as long as fuel and oxygen are supplied. Fuel cells are different from most batteries in requiring a continuous source of fuel and oxygen (usually from air) to sustain the chemical reaction, whereas in a battery the chemical energy usually comes from substances that are already present in the battery. Scheme of a proton-conducting fuel cellĪ fuel cell is an electrochemical cell that converts the chemical energy of a fuel (often hydrogen) and an oxidizing agent (often oxygen ) into electricity through a pair of redox reactions. ( February 2021)ĭemonstration model of a direct methanol fuel cell (black layered cube) in its enclosure. Please help update this article to reflect recent events or newly available information. So while they have some weaknesses, they've been good for me.This article needs to be updated. I lost the anti-rotation plastic clip on the u212d (the 212 never one), but it's the kind of thing that was easy to lose. My u212 head is a little more broken than the u212d, and even with the post attached as tightly as possible, still rotates a little. The QR posts do rotate annoyingly, a little more after the heads break. ![]() It would be nice to have a tripod with similar or better stability, and at least the same operating height, but maybe with 4 leg sections and without the geared center column, so it would be a little more portable. But even with the center column extended, they're pretty stable with my K100/200 and modest lenses. I found them somewhat marginal, with the center column fully extended, for my 35mm Canon A-1s. The essentially infinite leg angles are very helpful. Chunks have broken off both heads, in different ways (they're a different design), but the heads still hold cameras and work ok. I've gotten a lot of use out of my u212 and u212d. ![]()
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