In a small corner of dry, arid Colorado, inside a small electric enclosure, a compact but highly advanced piece of technology is helping to keep the power on for thousands of houses across a four-state region. This generation and transmission facility supplies power to dozens of power companies throughout Colorado, Nebraska, New Mexico and Wyoming, producing over 11 million megawatt-hours of power through coal, natural gas, and renewable sources.
Thousands of miles of cables, hundreds of workers, and dozens of facilities and power plants transform coal, gas, wind and sun into usable energy in an ongoing chain reaction of processes. One glitch in that chain can slow down energy production and cause undue strain on other sources to compensate.
Cleaning Coal: A Hot Job
One link in that chain is a 1,120-acre plant containing three coal fired units, with a combined output of 1,303 MW. Due to a widening awareness of climate change, coal fired plants are becoming increasingly regulated.
Many coal stations use selective catalytic reduction (SCR) reactors to comply with environmental regulations. SCR reactors use active catalysts to promote a chemical reaction that changes toxic nitrogen oxides (NOx) into friendly nitrogen and water. One of the products used in the process is ammonia, which if released, can cause more serious problems than the NOx itself. Software accurately controls the entire operation, and maintains the delicate balance, ensuring the safety of the process and plant.
Heat from the flue gas contained within the ductwork and reactor can cause irreparable damage to the sensitive multi-function electronic drives and servers that run the process. In order to keep the plant at a safe temperature for workers and electronic equipment, fans are installed in the ceiling of the plant to ventilate the enclosure and to cool the drives in the summer and keep them warm in the winter.
Fanning the Fans
Of course, the fans need protection too. Hot air rises, and fans are at the highest point of the facility and generate heat themselves. The SCR plant is a closed, insulated building, and temperatures regularly reach 90˚. The fans and circuit breakers are located about 190 feet above grade, on the same elevation as the flue gas duct work.
In the summer, temperatures peak above 100˚, hot enough to trip the circuit breakers for the fans, and losing the ventilation and cooling fans due to electrical overheating can create serious operational problems. When the fans go down, the temperature skyrockets above 100˚, limiting the time employees can safely spend in the area and potentially creating costly SCR downtime.
Tasked with keeping the fans and the operation running, the project team got rather creative. The electrician opened the 480V panel doors and positioned an air conditioner within a foot of the open enclosure. The team then shielded the area with an industrial curtain to contain the cool air. While this kept the operation running, it was cumbersome and costly.
The team purchased and installed a Vortec Panel Guard Enclosure Cooler, which they found online with a little help from an internet search. Installation was simple, even including a bit of 3/8’’ piping for clean air to reach the Vortec unit. It has been keeping the panels cool and continuously operating without the need for the air conditioners, or blankets.
Vortec’s enclosure coolers are designed around the vortex tube principle, providing an economical alternative with no moving parts. Vortex Tubes convert compressed air to a low-pressure cold air source to keep electronic enclosures and panel components protected so they can operate precisely. A compressed air stream enters the vortex tube where it spins rapidly, splitting into hot and cold air streams.
Cooling performance is easily adjusted by changing the inlet air pressure or by changing the generator in the tube itself. Vortex enclosure coolers also maintain a slight pressurization in the cabinet to keep circuit breakers clean and dry, preventing future trips even in the heat of late summer.
Vortec Panel Guards operate in environments up to 175 ˚, and are thermostatically controlled to reduce operating cost. Compared to the Freon A/C units which were previously used in this location, the Panel Guard is low maintenance, and saves energy without the use of toxic refrigerants. The enclosure remains cool with no ambient dirty or humid air, because the Panel Guard maintains slight pressurization inside.
Panel Guard Enclosure Coolers use a mechanical thermostat for optimum temperature control without the need for wiring. Installing the Panel Guard was quick and easy, and took about five minutes, despite the small size of the enclosure, 2’x3’.
Since installing the Vortex cooler, the plant electrician is proud to report that the fans’ circuits haven’t tripped, and the fans have been keeping the SCR facility cool and comfortable.
By keeping the circuit breakers cool, the Vortex Enclosure Cooler is just one small step in a long series of processes that powers thousands of homes across the West. The fans in this generating and transmission SCR facility have a tough job. Luckily, they have an even tougher enclosure cooler keeping their circuit breakers within an optimal temperature range to prevent tripping and overheating.