Equipped for Continuity
Business owners explore a wide variety of electrical equipment options and renewable energy alternatives for their backup power operations.
It’s difficult to imagine a business to which backup power is more critical than Appica.com, a Cincinnati, OH-based provider of private data center space, hosted applications, cloud computing capacity, and network storage. Redundant security is a major element of how the firm defines itself, both in terms of clients’ data and equipment, and the power supply to the equipment. Any unauthorized personnel attempting to access an infrastructure cabinet would run into five layers of security; the cabinets themselves are electronically secure and provide 24/7 notification of unauthorized attempts at access. The company, which was founded in 2002, also uses a redundant flywheel UPS system to prevent outages from compromising data center cooling infrastructure and, thus, data security.
Aaron Larkins, Appica’s president and CEO, says that UPS redundancy has always been considered mandatory at the company’s 23,000-square-foot facility, which can be expanded by 12,000 additional square feet. Until late 2008, two separate battery-based systems had been used as a redundant UPS for the company’s single generator.
Many communities are considering, researching, or implementing microgrid solutions. The underlying rationale often involves complex business, operational, and economic issues. See our FREE Special Report: Understanding Microgrids
. Download it now!
“We have public company clients, medical groups, and large manufacturing multi-site companies that rely on our data center to access their business applications,” says Larkins. “So we made a decision that we would have a primary and redundant power source from the UPS forward to ensure that no matter what happens in that primary line, whether it’s a fatal problem with the UPS, or the power distribution unit [PDU], or the circuit breakers that are feeding individual branch circuits, the customer has a secondary source of power.”
The company had a CleanSource UPS from Active Power installed for the redundant system, and then added a second unit for the primary system a little less than a year later, replacing battery UPS systems that had reached the end of their service lives. Profitability.net’s experience demonstrates the choices in equipment that managers at companies in a wide variety of industries have in protecting their power supply.
Add Distributed Energy Weekly and Energy Storage Solutions to your Newsletter Preferences and keep up with the latest articles stored and distributed power, battery storage solar microgrids, HVAC options, and smart energy systems and LED lighting retrofits.
The CleanSource UPS uses a flywheel that normally spins at 7,700 rpm and stores kinetic energy. In event of a power outage, discharge energy from the flywheel provides about 15 seconds of “ride-through” power, typically a sufficient length of time for standby generators to kick in. According to the manufacturer, the system is 98% efficient. The flywheel is located between top and bottom mechanical bearings and the entire unit is enclosed in a cast-iron housing. Rather than turning on a vertical shaft, magnetic pulses turn the flywheel. The UPS steadies the kinetic energy produced by the flywheel to a 480-V, 60-Hertz output, and an automatic transfer switch transfers power from the flywheel to the standby system.
Each client’s cabinet has a primary and redundant power source from the UPS forward. Each UPS feeds its own PDU that feeds the individual cabinets.
“The flywheel systems are designed to give us sufficient run time until our generators start up, which in our case, is a little less than 10 seconds in the event of a power outage or voltage drop in the grid,” says Larkins. Each system never has more than a 50% load, allowing a “bridge” of longer than 15 seconds should a power outage or voltage drop occur.
“In this business, power infrastructure investments are pretty substantial, and you have to take the long view on what your costs of operation are going to be over time,” points out Larkins. “Our analysis showed that energy costs were already starting to pop up, and our thought was that energy isn’t going to get any cheaper over the next 10 or 15 years, so whatever we deploy needs to be the highest-efficiency available.”
Larkins adds that the new system also offers continual monitoring capability. “Stored kinetic energy doesn’t lie—if you’ve got a wheel rotating at a certain rpm [revolutions per minute], you know you have a certain amount of power,” he says.
The system performed as intended during a brief power outage along the downtown Cincinnati corridor shortly before 1 a.m. on July 24, 2009. The company’s monitoring systems immediately identified the power issue from Duke Energy and signaled the generator power system to start. The transition occurred in less than 10 seconds.
“Before [the outage], we had a confidence level that they would work, because we saw them in operation every day and we saw the consistency in how they performed,” says Larkins. He adds that the company has realized financial benefits from the new installation as well. It was possible to shut down one of two 10-ton air conditioners that were dedicated to the UPS room. Additionally, the company saves about $18,000 in the form of lower maintenance costs every year since the installation, according to Larkins.
Growth Meets Modularity
When Atlantic.net, an Orlando, FL-based provider of business data services such as server colocation, dedicated servers, data backup, security, and private networks looked at the impact of future growth on its 25,000-square foot facility, it was clear that growth, reliable power, and sustainability did not have to be mutually exclusive.
In 2003, the company built the facility—which is fully steel reinforced and meets Category 5 hurricane requirements—and had two Eaton 9315 battery-powered UPS units rated at 225–750 kVA installed. By 2007, the 9315s had reached capacity and the company began looking to expand its UPS capacity. Minimizing energy consumption and costs were a major consideration, however.
“We have global customers, so just because we’re in the Eastern time zone, that doesn’t mean that when we go home, our clients stop working,” points out Brett Haines, operations manager for Atlantic.net, which was founded in 1994. “We need to have 100% uptime—that’s something that we have to guarantee to our customers and we have to provide it. A UPS helps us to guarantee 100% uptime,” he says, adding that the company serves several industries in which data is critical, such as travel and medical, and small companies to multimillion-dollar corporations.
Haines acknowledges that Atlantic.net is served well by its power supplier, Progress Energy, which routinely conducts line tests and trims trees located near wires. Normally, problems only occur with the power supply as a result of human mishaps, he adds. Regardless, the company employs a 2-MW Caterpillar generator for standby power and management recognizes the importance of a foolproof power supply.
But like nearly everyone, management also recognized the fact that energy costs had been steadily ticking upward during the past decade. Clients were making infrastructure adjustments to try and keep up. The company responded to the demand by opting for new high-efficiency, modular Eaton BladeUPS systems for the server racks.
“More and more, our clients have been virtualizing the components that they use—they’re going from more servers down to a few,” says Haines. “As more clients come in and use our space, the virtualization helps because it reduces our power needs, but as more clients come in, we need more power. In those fewer servers, they’re using more energy and they’re also putting out more heat, so we try to minimize our heat load on the floor as much as possible, and the BladeUPS help because they’re more efficient.”
The BladeUPS system is a three-phase, rack-based UPS system new three-phase system designed primarily for modularity. According to the manufacturer, users can expand their UPS capacity from 12 kW to 60 kW in a 19-inch enclosure by adding from one to six parallel BladeUPS modules to create redundancy. The units reportedly provide up to 34 minutes of run time and are 98% efficient.
As of early fall 2010, Atlantic.net had installed nine BladeUPS racks and a total of 50 modules, in addition to the two Eaton 9315s still in service. Haines reports that bridges typically last 15 seconds with a maximum of 29 seconds, not that it has been put to use very often. One time, a car had struck a power pole and an entire grid section was shut down, according to Haines. The UPS bridged the outage for 20 seconds, and the generator ran for two hours with no adverse impact on clients’ equipment.
The modularity of the new UPS system suits cloud computing, an Atlantic.net capability. “As more clients come, we’re going to need more computers online for our new cloud product,” says Haines. “The way we can do that with our UPSs is to put in redundant UPS systems. What we did was put two BladeUPS modules into each rack so now, in case one component fails or a battery isn’t up to par, we have those in place.
“As you increase the load, UPSs become more efficient and you don’t want to have large 400- or 500-KVa modules sitting there with 10% load—that’s not very efficient.” He adds that the BladeUPS modules operate at 40% for “fail-over” capability.
Medical Facility Goes Green With Flywheels
Beth Israel Deaconess Medical Center (BIDMC) in Boston, MA, a 550-bed adult medical-surgical teaching hospital affiliated with Harvard Medical School, recently established a goal to increase green purchasing by 15% by Fiscal Year 2012. A major element of this initiative is the selection of “clean energy” flywheel systems to help protect the BIDMC’s two data centers against power outages. The main 7,000 square-foot Renaissance Data Center is located 1.5 miles from BIDMC’s hospital campus and the separate Span Data Center 3,000-square-foot disaster recovery data center is housed at the main campus. These data centers provide critical clinical support to the facility’s medical records, pharmacy, laboratory, chemotherapy suite, and operating rooms.
The UPSs protecting the servers, switches, routers, data storage devices, and PDUs utilize flywheel systems from Vycon. The Span Data Center contains a standalone 225-kVA UPS that uses two Vycon flywheels rated at 275 kVA for 11.7 seconds. A 200-kW computer load provides 15 seconds of run time on the flywheel before the generator starts. The BIDMC staff is in the process of making this facility’s electrical and cooling systems as redundant as those in the Renaissance Data Center. The latter facility receives power from the utility vault through four automatic transfer switches (ATSs) that switch to a generator during a prolonged power event. The cooling system and computer load are supported by two sets of redundant ATSs; if either one loses an ATS, the data center remains operational.
Two sets of Vycon VDC flywheels to back up the two parallel 225kVA UPSs. According to Ty Dell, data center plant manager for information systems, during a power outage the facility obtains 30 seconds of flywheel runtime at 400 kW of computer load before the generator starts up. Dell points out that this is plenty of time, as the generator must come online within 10 seconds in order to meet the National Fire Protection Association’s NFPA 99 regulations for Emergency Power Systems; the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) requires that the generator must come online within 12 seconds.
The flywheels have a maximum energy storage of 3,000 kW per second at 100 kW and a rotational speed of 18,500 to 36,000 rpm. For the short term, management is opting to use batteries and the flywheel systems in tandem. Dell reports that the staff is currently evaluating whether to eliminate the batteries, noting that a rapid flywheel recharge time of less than 150 seconds provides reliability and that the flywheels do not require special cooling.
Redundancy in Standby Generators
Redundancy is often a high priority for standby generators, too. That was definitely the case for Columbus, OH-based Ecommerce Inc., a company founded in late 1999 that houses nearly half a million Web sites or nearly half of 1% of the Internet. In fall 2007, the firm was constructing a new data center in Columbus and was selecting a backup power solution and needed a scalable system to address future growth in the climate-controlled facility that would soon be filled with industrial-grade servers. One option was a single 2-MW generator and transfer switch with no redundancy, a solution that would have taken nearly a year to install.
Rick Gideon, vice president of operations for Ecommerce Inc., was introduced to an alternative redundant solution by chance. The company and Columbus-based Generator Systems Inc. (GSI) had the same real estate agent, which is how Gideon was introduced to GSI. He met with Brian Kennedy, vice president, sales and marketing for GSI, who recommended the Generac Modular Power System (MPS) for protecting Ecommerce, Inc.’s 10,000 1U server room. Rather than installing 2-MW gensets immediately, the company had two Generac 500-kW MPS Diesel generators installed that are providing 100% redundancy at a lower cost. Enough space is available to add three more 500-kW MPS Diesel units to allow for future growth within the facility.
A Different Kind of Medical Backup Power
Cardiac Equipment Services, Nassau County, NY, provides slightly different medical backup power systems that could be described as self-contained UPSs. The company is owned by Charlie Bergin, who has worked in the biomedical engineering field for 25 years—the past 15 as a provider of medical power backup systems. He often recommends one of two systems—OnStat Power Systems’ Reassurance or Silent Sentry—for office-based surgical centers.
The Reassurance product, developed by Medi+Products in the early 1990s, is a fully enclosed, stainless steel, cabinet system on a castor base. The top surface has a 30-inch height and the unit is equipped with front panel outlets.
The Silent Sentry is a static subpanel designed for minimal impact on interior design. The unit provides 2,000, 2500, or 3,000 W and 4 kWh of stored energy, and is based on 12-V battery banks with built-in UL-489 branch-circuit protectors for distributed loads. It can be inset into a wall cavity between wall studs and has a protrusion of as little as 4½ inches. The unit integrates branch-circuit interrupters into the system itself, making the battery-powered generator an uninterruptible subpanel, eliminating the need for an emergency subpanel.
The two units have several common features, including five-stage battery recharging, a recharger with four-stage automatic recharging and manual equalization, battery monitoring, an optional charge/discharge monitoring system for tracking energy in and out of the battery bank, and split-phase output.
Surgeons can plug their powered surgical equipment into these units to maintain procedural continuity. Bergin points out that the units are designed for procedures that are not life-threatening, such as gastroenterology and plastic surgery. “Many doctors are fearful,” says Bergin. “When the power goes out, they don’t know how long it’s going to be—they just want enough time to close and get out. They may not finish the procedure. It depends on where they are in the procedure—if it happens right at the beginning, they might just close up and have the patient come back.”
Still, JCAHO mandates two hours of standby power. Gastroenterologists power equipment such as vital sign monitors and O2 concentrators, and plastic surgeons need to wire entire operating rooms because they use general anesthesia.
“All of the procedures are elective, and all are outpatient,” says Bergin. “It’s not like they need hospital-based generators, which are diesel-based and located outside the building.”
Bergin indicates that a market for standby power for non-life-threatening medical procedures has been steadily growing in recent years. “Today, most outpatient surgery can be done in an ambulatory environment outside of the hospital,” he says. “It’s happening more and more where there are a lot more facilities opening that do opening types of surgery, from orthopedics to OB-Gyn.”
Service Platforms for Raised Tanks
Recent federal regulations have created a new market for aboveground storage tanks (ASTs) for fuel that is stored for use in equipment such as standby generators. In 1988, the US Environmental Protection Agency (EPA) mandated that underground storage tank (UST) owners comply with new standards for corrosion resistance, leak detection, and spillage and overfill protection by the end of 1998.
This regulatory development has created a market for related equipment: AST platforms. Larry Hill, CEO of Collierville, TN-based Generator System Support (GSS) and engineering manager at Thompson Power Corp. in Memphis, TN, points out that the proliferation of ASTs has meant that gensets are sometimes located too high for proper service and maintenance. GSS constructs aluminum service platforms that allow access to two sides and one end of gensets.
The platforms use 0.125-inch aluminum tread plate material that is bolted together in the field. Platforms in the standard configuration do not touch the concrete pad; they have a cantilever design that uses the fuel tank base as the supporting member. The platform usually is located 36–48 inches above the concrete pad.