Power on the Move

Nov. 27, 2012
New products and expanding technology in the world of portable power generators are bringing great benefits to end-users. And it seems that the range of end users is also expanding. From utilities that need to boost weak transmission lines to commercial enterprises that can’t afford less than 100% reliability from the grid, portable power can offer a wide range of advantages. Then too, maybe you’re just throwing a weekend party for 20,000 of your friends, with catering, camping, and entertainment included. A blackout could easily have everybody singing the blues.

Portable power keeps the party going for Jay Goldberg, president of Jay Goldberg Events & Entertainment, Peoria, IL. Goldberg is well known for throwing a wild weekend party known as the Summer Camp Music Festival, and he’s seen the event grow from a few hundred attendees to 20,000. Summer Camp’s portable generator needs have also grown, from a single Caterpillar unit, to 19. The generators are spread out across Three Sisters Park, Chillicothe, IL, and they provide power for music, food and merchandise vendors, plus an RV park.

“We have many festivals and we use portable power at all of them,” says Goldberg, “and we are known for holding events on somewhat primitive grounds. At the Summer Camp, we had to supply electricity to seven different stages featuring 100 bands, and vendors that supply food and merchandise. Then we have arts and crafts vendors, and educational displays, and we actually power a 200-space parking lot for RVs. This is all supported by the Caterpillar portable generators.”

Goldberg likes the low noise performance of the Caterpillar generators, and he notes that the dealer support from Altoforfer Power Systems, Peoria, IL, has always been available to meet his requirements. Moreover, when he wanted to burn biodiesel fuel, Caterpillar stepped in to support his request. “Our fuel supplier was concerned about using this type of fuel, but Caterpillar ran a test and approved a 20% mix of biodiesel. This is in line with our philosophy of having all of the participants and vendors use only biodegradable and recyclable products.”

Such environmental concerns are reshaping product designs for generator manufacturers throughout the industry. At Caterpillar’s division of Cat Rental Power, Peoria, IL, the company recently introduced two new mobile diesel generator sets that meet Tier 4 Interim emission regulations. The XQ200 and XQ350. The XQ200 relies on Cat’s C7.1 engine for fuel efficiency in delivering a prime operation rating of 182 kW. The XQ350 uses Cat’s C13 engine, rated for prime operation at 320 kW.

“The XQ stands for extra quiet,” says Joseph G. Fiorito, CEM CEP, North America business development manager, Cat Rental Power. “Each time we release a new model we improve the features and technology. We made the engine tamperproof and all of our units have very long robust performance because rental vehicles in general aren’t given the most loving care and attention. These units are designed to be a hit with a power washer to clean the radiator, and open hardware such as the wiring is designed to last in an extreme environment. You can take these to Arizona where the temperature reaches 115 degrees, or Alaska where it’s below 50 degrees, because we make sure that all the components can withstand the elements.”

The XQ200 and 350 can also withstand voltage and frequency changes, as they’re equipped with new EMCP 4.2 control panels that feature a user-friendly interface and auto-configuration of key performance parameters for voltage or frequency changes. Ground fault circuit interrupter (GFCI) receptacles consistently run at 110 V, regardless of the voltage at the main loads bus terminal, and the units feature 30 and 50 amp connectors with twist lock connectors. Solar-powered battery chargers are an additional new feature.

Fiorito has seen portable power usage from the perspective of both a customer and vendor. He’s been with Caterpillar’s Rental Power Division for more than 12 years, but previously worked for electric utility Commonwealth Edison for 10 years in various capacities from Powerplant Engineer to Senior Purchasing. He notes that in the rental market, peak shaving has been a very attractive opportunity. “In Chicago back in the late “˜90s, we had 300 megawatts of distributed generation to offset the peak power that was priced at over $1,000 a megawatt-hour. In those cases, the economics of running a diesel generator far outshine the fuel costs and customers would bring in the generators for one month or two without having the capital outlay issues for a permanent installation.”

Although peak shaving continues, the oil and gas industry has proven to be even bigger market for portable power, and maybe the most demanding. “In Canada, it’s an explosive area, and farther south in the Dakotas and Pennsylvania, it’s the biggest growth market for distributed energy and portable power in quite some time,” says Fiorito. “Most of these sites are very remote and rugged, and they are the toughest people in the world to work with. Sometimes the equipment literally gets dragged up a mile at a time.” Load demands are equally abusive, and generators powering heavy-duty pumps can see start up current loads of six times or more above the normal running current.

The need for portable power in oil fields and the availability of natural gas hasn’t been lost upon the industry and generator manufacturers such as GE Waukesha Gas Engines, Waukesha, WI, are responding. Waukesha has supplied its natural gas-fueled VGF Series F18GSID engines for temporary prime power applications in US oilfields. The gensets offer 265 kW of prime power across the Dakotas, Wyoming, and Montana. According to Dwain Williams, CEO at Northland Power Services, Gillette, WY, and the demand for gas-fueled generators is skyrocketing at oil field operations.

Waukesha’s line has grown to meet the demand, and the company has added 12- and 16-cylander units to its 275Gl Series of products. The engines are designed to produce more power on low-quality gas pumped directly from the ground, and can tolerate fuels with heating values down to 600 BTU per cubic foot. Power outputs range from 2,600 kW to 3,480 kW in various configurations. Along with Waukesha’s reciprocating engines, GE Power and Water, Schenectady, NY, also offers portable gensets with gas turbine power, and recently announced a milestone in their production history.

In September 2012, GE celebrated the production of its 100th trailer-mounted TM2500 aeroderivative gas turbine. It’s been in production over a decade and GE refers to as the “power plant on wheels,” although the latest model requires a few less wheels than the original, notes Brian Boutte, general manager for PowerXpand, a portfolio of several GE technologies that help customers address temporary power needs or permanent power. “Originally, the entire package needed three trailers, but now the controls and fuel and generator are mounted on two, 55-foot trailers,” says Boutte. “So this aviation derivative engine has a small footprint but high reliability and fuel flexibility. It can burn natural gas, but in Brazil they use sugarcane-based ethanol.” GE has a remote monitoring facility outside of Houston, TX, and Boutte adds that the company monitors 2,400 aero derivatives from the facility. As part of GE’s PowerXpand portfolio, the TM2500 fills out a line of products that range from 1 MW to 31 MW, and also include products from Waukesha and Jenbacher.

For a highly mobile and lightweight approach to using a turbine related to the aeronautics industry, Turbine Marine products, Pompano Beach, FL, offers something unique, a 1.1-MW, turbine-driven genset that weighs just 9,000 pounds, and measures 12 feet long by 5 feet wide by 5 feet high. The turbine is a Lycoming T-53 Engine, the US Military’s choice of power for its UH-1 and Cobra Helicopters. “We’ve made this product lightweight in case it needs to be transported by a crane or helicopter,” explains John Arruda, president. “It’s very small, about the same size as a 180-kilowatt diesel genset, and I tow it with a [Cadillac] Escalade. Typically, a unit of this power would be stored in a 20- or 40-foot ISO container and have to be moved with a semi truck. In some applications, that’s just impractical.”

The small turbine doesn’t vibrate as a reciprocating engine would, and though the sound level is around 90 dBA, its character is similar to white noise. “It’s just a whole different type operation,” adds Arruda, “and you can burn any kind of fuel you like. From Number 16 fuel oil, to diesel, kerosene, gasoline, ethanol, or methanol. This turbine doesn’t care, and fuels can be changed at any point in time, or they can be mixed.” The Marine Turbine has seen use in a variety of standby and emergency applications, from water distillation plants to temporary disaster housing, and an 850-kW model is also available.

New product introductions are adding variety to portable generation offerings from Girtz Industries, Monticello, IN, according to Brent Beissler, engineering manager. “We are introducing a 480- to 600-volt auto switching unit, and it does this without a link board,” says Beissler. “Instead, it just uses the controls of the switchgear to change the voltage of the generator. So for the customer, it’s very transparent. You just flip a switch and change from 480 to 600 volts. This comes into play with the Canadian customers, because the majority of applications are 600 volts, but they do have applications for 480 volts. It’s available in any of our main sizes of 500 kilowatts, 1015 kilowatts, and 2,000 kilowatts.”

Girtz has also developed a portable switchgear interface that allows customers to parallel together gensets from different manufacturers. “It’s a piece of switchgear that’s about the size of a suitcase, and you can hook the load sharing lines of various gensets together,” says Beissler. “So, you have a Caterpillar talking to an MTU, a Cummins, or others, and they’re synchronized and ready to go.” User-friendly designs and easy operations are a key factor for Girtz products. The company designs and builds its switchgear with touch screens that have simple graphical user interfaces, and line drawings right on the controls. Gensets in the company’s Z-CUBE line include 400600 kW, 6001,250 kW, and 1,2502,250 kW.

Beissler notes that Girtz has seen demand from customers for a line of natural gas gensets, and the company will be expanding the Z-CUBE line to accommodate the requests. “Natural is growing in popularity, but from an electrical load standpoint, you have to look at how you’re applying it, because gas doesn’t like very high block loads. For a diesel you can go from zero to 280% of the maximum in two seconds. But with a natural gas engine, the end user has to understand what their loads are. If it’s an industry that has big motors that demand 400 kilowatts at startup load, plus a difficult power factor, an oversized genset or two gas gensets could be used to distribute the load.”

Although natural gas is on the rise, diesel still plays a major role in portable energy, says Patrick Herrley, electrical engineer, Tognum Inc./MTU Onsite Energy, Novi, MI. “Natural gas requires infrastructure availability,” says Herrley. “Whereas, the sites that don’t have the infrastructure can use diesel generator sets that require no setup time. For the rental market ours are plug-and-play and can be in operation in the time it takes to connect the load and push the start button.”

MTU recently unveiled a new, 50-kW integrated standby power module at a trade show for another profitable market for portable power, the International Cellular Telecommunications Industry Association Wireless Show. The unit is specially designed for easy installation and operation at remote cell sites, and as Herrley mentioned, simple operations are at the top of feature list. The 50-kW module’s plug-and-play was designed to eliminate many typical contractor interconnection errors, reducing installation time from a week or more to as little as one day. It features an integral automatic transfer switch for load transfer and a compact footprint of 110 inches by 40 inches.

For higher power needs, MTU has a new, 1,000-kW power module in its line of mobile and rental generator sets for prime or emergency power applications. At a prime-rated load factor of 75%, the product is designed for demanding applications such as special events, emergency recovery, construction, rock quarries, or powering industrial processes. The power modules feature digital controls and convenient enclosure access points, for easy operation and service.

The unit is housed in a 40-foot ISO container, rated to 50°C (122°F) ambient and is designed for the most extreme environments. Sound production is limited by the enclosure to 75 dBA at full power. Cooling air is redirected to reduce airflow sound and exhaust noise is reduced by a custom internal silencer.

The level of sound produced by portable generators can be difficult to control, according to Jeff Crisman, an engineer with Enercon Engineering, East Peoria, IL. Enercon does custom design and manufacturing of controls, switchgear, packaging, and enclosures, for power modules, and cogeneration units. “Sound is one of the biggest challenges we have because you have a system that can run at a 113 DBA rating, and it’s deafening-even louder than a chainsaw,” says Crisman. “When you set this up in a residential location, you have to remember that when you put something that’s noisy in an area, you raise the level by three DBA. If a site has a requirement for 60 DBA at one meter, it’s very complicated. We can get them quieter, but obviously it’s costly and requires custom enclosures with thick walls and larger silencers.”

Enercon and other power engineering firms may soon find it less costly to reduce sound as Cummins Power Generation has invested in a new Acoustical Testing Center inFridley, MN. This includes a state-of-the-art hemi-anechoic (no echo) chamber, where researchers can precisely measure the noise output from fully assembled generator sets of all types and sizes. Pinpointing the sources of noise in a generator set helps Cummins Power Generation design quieter products.

Features such as sound attenuation in multiple configurations to meet local requirements are included in new products from Cummins Power Generation that address the market for mobile generators in the range of 60 kW to 2 MW. In this case, Cummins has introduced a new line of trailerized mobile generator sets at ratings of 60-, 80-, 100-, 150-, 200- and 300-kW nodes. This full range of mobile gensets from 60 kW to 2 MW are designed as pre-integrated turnkey packages, ready to go to work in situations such as prime power, backup power for scheduled maintenance, emergency power after a natural disaster, and standby/peaking power for large utilities. These units are primarily targeted for sale to Power Rental companies. Also new to the market are the C150D6R and C200D6R Mobile Generator Sets, both certified to EPA Nonroad Tier 4 Interim (Tier 4i) emissions levels. The new Tier 4i models are rated at 150- and 200-kW capacity, respectively.

According to Larry Fetting, Rental Segment General Manager of Americas at Cummins Power Generation, “In this economy, people are asking “˜how can I do more with less’,” says Fetting, “One thing we’re seeing is that companies are using mobile gensets and docking stations for site backup. If a storm hits your building, the onsite genset can be damaged. Having a remotely stored backup and docking stations can allow for immediate hookup of a mobile genset. The mobile unit is allocated to cover more then one site, thereby lowering backup power costs.”

Cummin’s mobile generators have also been a great success for peak shaving in the company’s global market. “The best example is FirstEnergy, and our products were there for several years,” recalls Fetting. “Initially, this was a pure monthly rental arrangement. Then, they were uncertain about their financial prospects of the approach. Our Six Sigma team looked at the wholesale cost of electricity, which clears at a new price every five minutes. We analyzed those prices over several utility locations and came up with the conclusion that the financials worked well and developed a cost sharing plan with FirstEnergy, so when we ran our units, we would share in the savings.” The price analysis was persuasive, but the savings had an even greater impact. During one particular week, FirstEnergy found that the price of energy on the spot market was selling at over $900 per megawatt-hour, yet their diesel-generated power costs were just $150 per megawatt-hour, yielding a net savings to the utility of nearly $2 million for that week.

FirstEnergy has also found a use for mobile fuel cells during peak demand events, and has entered its first year of operating a 1-MW system at its Eastlake plant in Cleveland, OH. The CLEARgen unit uses proton exchange membrane technology from Ballard Power Systems, Burnaby, British Columbia. The system is composed of nine, 150-kW modules installed in a trailer for convenient transport. As for sound issues, there aren’t any, since fuel cells run at sound levels that are all but negligible.

The fuel cell industry has struggled for many years with issues of profitability, but there’s no denying the progress that’s been made. In May 2012, the Department of Energy (DOE) announced that more than one thousand fuel cells were deployed through the American Recovery and Reinvestment Act (ARRA), with nearly 700 fuel cells in place to provide backup power. The DOE cites commercial buildings, data centers and cell phone towers as prime markets for the technology’s benefits of quiet operation, and low emissions due to the use of fuel sources other than petroleum.

The progress reflects an investment from the ARRA of about $28 million, and such investments are another area the fuel cell industry has struggled with. But the manufacturers have some hope with the news that the Senate Fuel Cell Caucus has re-launched, after a break due to the retirement of Sen. Byron Dorgan of North Dakota. Many industry representatives attended an event to celebrate the re-launch, including Katrina Fritz-Intwala, director Business Development and Public Relations, at UTC Power, South Windsor, CT.

Over the years, UTC Power has racked up an impressive customer base that includes, Coca Cola, Whole Foods Markets, Saint Francis Hospital, and Eastern Connecticut State University. “We have several repeat customers such as Coca-Cola and St. Francis Hospital,” notes Fritz-Intwala. “These are commercial deployments rather than pilot programs because they are in use commercially and our customers achieve the energy savings they were looking for. A lot of the stores are using them for backup power as well because they deliver and perform.”

For St. Francis Hospital, the addition of a new fuel cell represents an upgrade to UTC Power’s latest 400-kW PureCell stationary fuel cell. Several years ago, the hospital began using UTC Power’s previous generation 200-kW fuel cell system to power part of their main campus in Hartford. The new PureCell system installations are for the main campus and the Mount Sinai campus (supplying 10% of the main campus’ electricity needs and 42% at the Mount Sinai campus). Both are configured as a combined cooling, heating and power (CHP) generation systems based on phosphoric acid fuel cell technology. Natural gas is the fuel and UTC cites total efficiency performance up to 90%.

According to Mark Carmichael, manager commercial business at UTC Power, the PureCell model 400 offers a number of benefits. “The biggest area is increasing the lifespan,” says Carmichael. “We already had a world-class durability and life on our cells stack, and we have continued the fuel cell’s life over 10 years before it needs an overhaul. But at the same time, we were able to learn on all the other subsystems as well. So, the durability and the reliability of all the systems that support the fuel cell in the stacks have improved, and the power plant as a whole has up to a 20-year expected life. And, with proper maintenance and service, there is no reason why this fuel cell couldn’t perform past 20 years.”

Fuel cell sales are also on the rise at Bloom Energy, Sunnyvale, CA. In July 2012, the company sold a 1-MW system to Life Technologies Corp., Carlsbad, CA. The system will supply about 60% of the company’s power requirements. Bloom Energy lists the Coca-Cola Company, eBay, FedEx, Google, Apple, and Walmart among its customers. The issue of sustainability is cited as a factor in fuel cell purchases, and it gets a further boost when a company can claim to use biogas in their operations.

Such is the case with NTT America, New York, NY, a global infrastructure services provider that has deployed Bloom Energy Servers at its Lundy Data Center in San Jose, CA. The company cited biogas as the best choice to minimize its carbon footprint and decrease the amount of electricity pulled from the public grid, while at the same time reducing operating costs. The Bloom Energy Servers utilize biogas from a California dairy farm.

Whether it’s biogas or natural gas, a fuel cell has to use a process of reformation to extract hydrogen for its electrical energy conversion function, and that’s an additional step that could be avoided by starting with hydrogen as the fuel source. But there isn’t a hydrogen infrastructure comparable to natural gas. However, the problem is an opportunity for Air Products, Allentown, PA. The company recently launched its SmartFuel Portable-Power Cylinder, designed for hydrogen-fueled power applications. Air Products is targeting power requirements for operations in remote areas beyond utility power grids, and typical portable power situations such as temporary power usage.

We mentioned Ballard earlier, and remote site requirements have contributed to some substantial orders for the company. For example, in September 2012, Ballard shipped the first 100 Electragen TM fuel cell systems to Cascadiant Inc., distributers of Ballard products in Southeast Asia and South Africa. The systems are comprised of both direct hydrogen and methanol fuelled units. Wireless telecom service providers will deploy the systems. Ballard has another interesting project in South Korea, where GS Platech is using plasma gasification technology to treat organic solid waste to produce sufficient high purity hydrogen to generate 50 kW of electricity.

South Korea also happens to be the site of an 11.2-MW fuel cell power generation plant. According to FuelCell Energy, Danbury, CT, the project in Daegu City, is the world’s largest fuel cell electricity plant. It was developed by FuelCell Energy and Korean utility POSCO Power, and supplies electricity to about 20,000 South Korean homes, all from just four 2.8-MW Direct FuelCell power plants.

Back in Fuelcell Energy’s home state of Connecticut, the company recently announced the sale of a 1.4-MW system to Central Connecticut State University, New Britain, CT, to be used in a combined heat and power configuration. Both Fuelcell Energy and UTC Power have benefitted from Connecticut’s aggressive promotion of the state’s fuel cell industry. In the case of Central’s project, the Connecticut Clean Energy Finance and Investment Authority provided a grant, in connection with the Connecticut Clean Energy Fund Onsite Renewable Distributed Generation Program.

All told, there is wide variety of technologies and fuel choices available from the portable power industry. Moreover, manufacturers continue to introduce new products-from the latest in hydrogen applications, to the evolving natural gas technologies. And of course, with diesel engines there’s a century of performance history that continues to improve in areas such as meeting Tier 4 emissions regulations, and higher fuel efficiency ratings. So whether you’re throwing a party for 20,000 or supporting a utility transmission network for two million, portable power can provide a solution.
About the Author

Ed Ritchie

Ed Ritchie specializes in energy, transportation, and communication technologies.