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Anchorage Post Office cuts ribbon on fuel cell electrical system Nation’s largest commercial fuel cell system goes online; produces no harmful emissions; generates usable heat; provides uninterruptable power supply backup by The Associated Press PNA Contributing Writer
On Aug. 9 the Anchorage Post Office’s mail processing center at the Ted Stevens International Airport officially dedicated a state-of-the-art fuel cell system. The new system has been operating and subjected to operational tests during the last two months.
The system, capable of generating 1 megawatt of electrical power, is the largest commercial application of fuel cell technology in the nation and is more than large enough to power the post office. Chugach Electric Association Inc., owner of the system, will sell the excess power generated into the existing electrical grid.
The fuel cell system at the post office is made up of five fuel cells, each capable of producing 200 kilowatts of electrical power. Due to construction limitations, each fuel cell is designed and built as an independent 200 kilowatt unit. In a first for the fuel cell industry, the five fuel cells that comprise the post office’s system are electrically connected to act as a single, one-megawatt power plant. Uninterruptable power supply backup The post office application is also the first to use an automatic switching system to provide uninterruptable power backup in the event of a power grid outage. The system, under normal conditions, operates in “grid parallel” mode and is nothing more than additional power generation for the entire Chugach electrical grid. If the grid experiences any interruption in power, the automatic switching device automatically switches to “grid independent” mode and dedicates the fuel cell power to the post office. The device performs the switch “seamlessly” and is fast enough to prevent computers from going down.
This system was tested twice on the morning of the dedication. At about 8 a.m. a simulated power interruption was conducted and the switching device performed as expected, with no loss of power to the post office. Shortly after 9 a.m., a construction crew accidentally severed an electrical feed line to the post office. Technicians monitoring the fuel cell system observed the system switch from grid parallel to grid independent and asked if an unannounced test had been conducted. The post office reported that no loss of power had been detected in the mail processing center.
The Anchorage Mail Processing center is the major sorting and distribution point of mail going into and out of Alaska. Approximately 425 postal employees work at the facility in a 24-hour-a-day, seven-day-a-week operation. They process an average of 1.2 million pieces of mail per day. What a fuel cell is Like batteries, fuel cells generate electricity through an electrochemical process. A fuel cell consists of a positive electrode (cathode), a negative electrode (anode) and an electrolyte that conducts ions between the two. Multiple groupings of cathode, anode and electrolyte are stacked atop one another to form a fuel cell “stack” in sizes ranging from 1 kilowatt to as much as 250 kilowatts. Current construction techniques limit the size of a commercial fuel stack to about 200 kilowatts.
Each IFC PC25™ fuel cell generates 200 kilowatts of electricity, enough for more than 100 homes, and more than 700,000 Btu per hour of usable heat in hot water. The heat generated at the post office will be vented to the atmosphere during summer, but will be used to heat the facility during winter, increasing the center’s overall fuel efficiency.
Hydrogen is supplied as fuel to the anode side of the fuel cell and air is supplied as an oxidizer to the cathode side. The catalyst between the two splits the hydrogen molecules into protons and electrons. When the protons move to the cathode, they react with oxygen in the air to form carbon dioxide, water and heat, the only emissions of a fuel cell. The movement of the electrons to the cathode generates a direct current electrical charge. As in most applications of fuel cell technology, the post office system then converts the DC power into AC power for electrical use.
Since natural gas is one part carbon for every four parts hydrogen, the fuel to waste ratio is very good and the waste emitted is relatively harmless carbon dioxide, pure (drinkable) water, and usable heat. Present and future uses of DC power Transportation uses of fuel cell technology, such as automobiles, trucks, buses and trains will use the power generated by a fuel cell in the DC form. Unlike internal combustion engines that have relatively narrow ranges of operational speeds, DC electrical motors can be effectively used across their entire range of speed, from zero to their maximum speed. DC motors also have the potential to be used just as effectively in braking to slow the load and in that mode can, themselves, generate DC power.
Conventional train locomotives already use DC electricity to power the DC electrical motors that move the trains. They burn diesel fuel to generate the DC power with a fairly typical, diesel-engine-powered generator set, but the motors that move the train are DC electrical motors. Many players assist with the funding Research, development, manufacture and installation of the approximately $5.5 million fuel cell system was funded, in part, by Chugach Electric, the Postal Service, U.S. Department of Defense, Cooperative Research Network of the National Rural Electric Cooperative Association and the Electric Power Research Institute. The control system that ties the five cells together electrically and controls the automatic switching for the system was developed and funded by the DOD, U.S. Army Corps of Engineers and Construction Engineering and Research Laboratories.Dignitaries on hand for ribbon cutting Alaska U.S. Senator Ted Stevens and U.S. Postmaster General Bill Henderson were on hand for the dedication as were Eugene Bjornstad, general manager of Chugach Electric and William T. Miller, president of International Fuel Cells, maker of the fuel cell system. IFC is a subsidiary of United Technologies Corp. and is located in South Windsor, Conn.
“This project is another example of how our fuel cells can serve the commercial power market,” said Miller. “We are especially pleased to showcase the assured-power capability for a highly visible customer like the Postal Service.”
International Fuel Cells world leader International Fuel Cells is the world leader in fuel cell production, the company said, with its PC25™ commercial systems generating primary or supplementary power for data centers, wastewater treatment facilities, hospitals, hotels, schools, military installations and manufacturers.
IFC said it has delivered more than 200 fuel cell systems worldwide, is developing fuel cells for automobiles and supplies all fuel cells used on the Space Shuttle. Virtually any electrical power consumer requiring multiple kilowatts of power and needing an absolutely dependable, noninterrupted supply of that power is a likely candidate for the current level of fuel cell technology, the company said.
The only factor limiting a more widespread use of the technology is the high cost of purchasing and installing fuel cells. As more and more fuel cells go online, IFC said, the cost will fall dramatically and they will become economically viable options for an even wider market. Methane makes treatment plants, fuel cells a ready match Fuel cells produce electricity by splitting hydrogen molecules, and therefore, need a supply of pure hydrogen to function. In most applications, a hydrocarbon fuel, such as propane, natural gas or even gasoline is used. The hydrogen is stripped from the fuel in a separate process and then used to fuel the fuel cell.
One of the most attractive hydrocarbon fuels is methane gas and all waste water treatment plants have a ready supply being delivered to them every time a utility user flushes his or her commode. Without a fuel cell, the methane gas is a by-product of waste water treatment and has to be handled as such. Using a fuel cell to power the waste water treatment facility can make use of this continuous supply of methane gas and cut the power costs of the facility at the same time.
On June 1 the Los Angeles Department of Water and Power signed a contract with FuelCell Energy for a fuel cell power plant to be installed at its headquarters building. The new 250 kilowatt power plant is expected to be operational in about nine months. Arctic village of Nuiqsut sees fuel cell future As Alaska’s oil and gas industry works to bring the Alpine field into production, the Arctic village of Nuiqsut is making plans for a steady stream of natural gas that will soon start flowing toward it.
Nuiqsut’s village corporation, Kuukpik, will receive 500,000 cubic feet of gas a day. The corporation will turn the gas over to a non-profit cooperative created and owned by Nuiqsut residents. Some of the gas will replace the heating oil being used in homes.
Now the North Slope village wants to use a fuel cell to transform the gas into electricity. As a natural gas pipeline from the Alpine field nears completion, the village is looking to the federal government to help pay for the costly technology.
BP Exploration (Alaska) has committed $2 million for the cell and Sen. Stevens is trying to obtain a similar amount.
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