“Does it work?” is the question asked most often about any proposed new technology. It is then followed up by “Show me,” i.e., “Show me how this technology has worked somewhere real.” In Elizabethtown, PA, Masonic Village is a retirement community, children’s home, and community service organization. It opened in 1910. Today, the 1,400-acre campus serves more than 1,700 residents, and the staff numbers 1,300. In 2002, Masonic Village installed five C60 low-emission Capstone microturbines that produce a combined 300 kW of electricity. Did they work? In 2007, the microturbines were upgraded to C65 ICHP units, a heat-recovery module that generates 65 kW of electricity and ejects 408,000 BTUs an hour. In the five years between, the natural gas microturbines supplied existing baseload hot water needs, while simultaneously creating electric power. So, yes, they certainly worked. In 2011, the facility added a sixth Capstone C65 microturbine.
The new system produces 325 kW (25 kW more than the original Capstone installation). Masonic Village has seen a 47% increase in net heat recovered, and an overall system efficiency of approximately 83%. “The upgraded system at Masonic Village nearly doubles the thermal energy output of the microturbines and has increased the electricity produced,” explains Jeff Beiter, Managing Partner, E-Finity Distributed Generation, local distributor for Capstone. “There’s less
equipment than the original footprint, so the space impact is minimal. The return on investment is quick on a project of this caliber because of the increased system efficiency.”
In the upgrade of 2007 a five-year Capstone Factory Protection Plan was included, with a second complete overhaul scheduled after the next 40,000 hours of operation. Another major overhaul should not be needed until 2017. Clearly, this technique with microturbines for onsite power works, and not for just a few months.
Multiple microturbines provide energy security.
Sixteen Microturbines at Work
All the way across the country from Masonic Village in Pennsylvania, in Simi Valley, CA, is the Ronald Reagan Presidential Library. Administrators wanted an innovative, efficient, environmentally friendly energy system for the facility. “The environment is a big concern for a lot of businesses, as it is for us,” observes John Lehne, Facilities Manager at the library. “We wanted to make sure the system we installed provided not only the needs and requirements of cooling and energizing the building, but also leaving as little of a carbon footprint on the environment.”
The Library has 100,000 square feet and gets 95% of its energy from 16 Capstone microturbines. (It also provides electricity for the Air Force One Pavilion.) The installed system comprises three PureComfort packages (from UTC), each with four microturbines and a Carrier absorption chiller. There are also four standalone Capstone C60 (60-kW) units. In addition to providing 960 kW of electricity, the microturbines give heating and cooling for the buildings through combined cooling, heating, and power (CCHP). This trigeneration method adds to the Library system’s efficiency by using recyclable heat from power generation for heating, cooling, or industrial process purposes. How well has it worked? That system was installed in 2005, and since then it has enjoyed 24/7 availability and needed only routine filter changes for maintenance.
“The turbines have only one moving part and air bearings,” explains Darren Jamison, Capstone President and CEO. “There’s no oil, no anti-freeze, so it’s a highly reliable, simple design.”
“A lot of people didn’t know about this type of system when we installed it,” says Lehne. “A lot of people still don’t know about microturbines. The system gives us the efficiency we were looking for. It provides power for the full campus and is clean burning.” The turbines run on natural gas, which has a much lower environmental impact than traditional fuels.
Back eastwards now to Gainesville, FL, where the Shands HealthCare Cancer Hospital has benefited from a turbine-based CHP system for energy, heating, and cooling. The authorities and companies that collaborated in this project were the Gainesville Regional Utilities (GRU), Shands HealthCare, the University of Florida, and Burns & McDonnell (a full service engineering, procurement, and construction company.) The GRU South Energy Center used sustainable construction techniques and energy efficiency measures to make the modular plant the first hospital in the southeast of the US to be awarded gold-level certification in the LEED program.
The energy center has a 4.3-MW Mercury 50 recuperated gas turbine (from Solar Turbines, a Caterpillar company) as the facility’s prime mover. The Mercury 50 was chosen for its reliability (Solar has some 14,000 turbines working worldwide), low carbon footprint design, and enhanced quality of power production that provides uninterrupted operation of clinical devices at the hospital. The reliability of the CHP system is increased by the use of multiple redundant systems and by being housed in a structure (in Florida) designed to withstand Category 4 hurricane force winds. The system can provide 100% of the hospital’s electric needs and can operate at a 75% total thermal efficiency.
From the West Coast to the East Coast, and Now Into the Middle
In Maywood, IL, the Loyola University Medical Center had to replace 50-year-old natural gas steam boilers with . . . with what? Straightforward replacements would have been most expensive . . . too expensive. So, the Medical Center invested in a gas-turbine-based combined heat and power facility that generates almost all its electricity, while it provides at the same time low cost steam. Reliability was essential. The hospital has 536 beds and a 70-acre campus around it. Also important in the decision to go this way were the plans to reduce energy consumption and cost, to achieve high overall energy efficiency, and to meet the stringent air and noise emissions regulations of the hospital’s neighborhood.
The heart of the cogeneration system are two Taurus 60 gas turbine generator sets (from Solar Turbines). Solar was selected as the single source to design and build the plant under an “engineer, procure, and construct” contract. The extended scope of the supply included detailed design and construction, heat recovery steam generators (HRSG), fuel gas compressors, the motor control center, electrical interconnection with the utility, a building to house the plant, and a long-term service agreement.
At the Loyola University Medical Center the two Taurus 60 natural gas turbine generator sets provide 11 MW of electricity and can operate in a stand-alone mode should there be a utility power outage. Under full load, the CHP system operates at 81.9% efficiency and, compared with the sources of electricity and steam it replaces, reduces carbon dioxide (CO2) emissions by 34,934 tons per year. That’s like removing the equivalent of the annual emissions of 5,955 cars or planting 9,525 acres of forest. The exhaust from the Taurus 60 gas turbine generator sets goes to two HRSGs that can produce 180,000 pph of steam. The steam is used for medical equipment sterilization, food preparation, comfort heating, and the operation of several absorption chillers for cooling in the summer. The heat recovery boilers provide local hot water for 32 buildings at the center.
From Sea Propulsion to Land Power
There have never been many manufacturers of turbines for on land, onsite power. Now we see a company that has been a leader in turbine power for offshore applications, Turbine Marine Inc., entering the industrial, onsite power market.
“Three years ago, Turbines Marine, Inc. entered the industrial market using the same engines, T-53 gas turbines, for new products,” explains John Arruda, president of the company. “Our years of experience developing lighter and faster offshore race boats are crucial to the understanding of our ability to realize its design of a compact, lightweight, portable power generator, that is resistant to a wide range of weather conditions. The 1.1 megawatt is streamlined, and designed for transport by helicopter and mounted on its own easily detachable trailer for ground transport. With units ranging from 8,000 to 9,000 pounds, and dimensions of approximately 12 feet long by 5 feet wide by 7.5 feet high, the units manufactured by Turbine Marine are the lightest and most portable units for their power on the market today.”
This unique line of Compact Series turbine power generators are manufactured with industry standard components, including Marathon or Stamford electric generators and Woodward controls for engine management and electrical current monitoring. The unit has a full digital control panel that is also capable of synchronizing multiple generator units. These 1.1-MW assemblies can be ordered in any hertz or voltage configuration that the application may demand. The high-tech carbon fiber, weather resistant enclosure houses a self-monitoring safety and shut down system, as well as a dust/saltwater mist air filtration system for both the generator and alternator. By the use of a built-in air-lift apparatus, the generator can be lifted by a medium-size helicopter, and, due to its built-in trailer system and weather-resistant enclosure, it can be easily moved by pick-up truck, flat-bed truck, or fork lift, and stored anywhere, inside or out.
“The remanufactured Lycoming T-53, 1500-horsepower aviation engines that power Turbine Marine’s products are well-known, durable, and have decades of reliable service in civil and military applications,” adds Arruda. “They are reported to be easy to operate and service. They operate in all relevant temperatures and altitudes, and may be run on a vast variety of fuels, including jet A, diesel, gasoline, and biofuels, without any changes to the unit. A natural gas generator is also available making the unit more environmentally friendly. Due to the versatility of fuel types, the emission levels vary based on the fuel used. Other relevant features include a db sound level of approximately 92 db’s at 10 meters. Mufflers can be made for the unit, but at the cost of added weight. All the equipment is tested and factory certified at the manufacturing facility, in Pompano Beach, Florida.”
Noise and Other Community Concerns
One of my neighbors can’t do anything outside without making a lot of noise. For cutting the grass, trimming bushes, sweeping the driveway, clearing snow, or anything, he has to have a loud motor or engine to do it. His hearing isn’t so good now, so he cannot hear the comments made by his neighbors. Noise is annoying. Machines with big sounds can be annoying for more than just a few neighbors; the air-conditioning system on our hospital roof encourages growls and mutterings. When I mentioned microturbines to somebody the other day, he told me: “All those engines are so noisy. Why would you want one near you?”
Microturbines are not so noisy. They are significantly quieter than the reciprocating engines to which we’ve been accustomed in, for example, construction machinery and some backup power systems.
Concern for the environment, be it noise, air pollution, or simply wasted energy, is justified in a community. In a typical power plant, some two-thirds of the power is lost from the generation site to the end facility. We should be concerned about that, in the same way we should be concerned that much of the water leaked through faulty pipes is expensive because it has already been treated to make it drinkable. In an average year, a typical coal plant generates 500 tons of small airborne particles; they can cause chronic bronchitis, aggravated asthma, even premature death, as well as their recognized ability to make visibility worse. A typical coal plant generates 170 pounds of mercury. One 70th of a teaspoon dropped into a 25-acre lake can make the fish unsafe to eat. In an average year, a typical coal plant generates 3,700,000 tons of CO2, about the same as cutting down 161 million trees. These aren’t numbers meant to menace or frighten; they are numbers that reveal how poor our energy provisions of yesteryear have been in their attitude to community health. It’s not been a deliberate attempt to poison anybody, but today there are better technologies. Microturbines for onsite power are one of those technologies.
In that same vein-this time in relation to emissions-here’s some facts about Capstone MicroTurbines, as opposed to traditional piston engines. The Capstone Natural Gas fueled microturbines are the only engines certified to the CARB On-Road Heavy-Duty Engine emissions levels for Model Year 2011 that operate with no exhaust after treatment. Test emissions for from both the C30 and C65 Natural Gas microturbines measured dramatically less than the emissions levels set forth by the CARB standard, including NOX at 75% and CO at 96% less than the required levels. Local air permits and exhaust cleanup stipulations are not required as they are with piston engines. At a less dramatic level, but with practical advantages, microturbines have low-maintenance air bearings, as opposed to the high-maintenance required for piston engines with many moving parts.
Microturbines have integrated utility protection and synchronizing, contrasted with the other engines that require external relays and control equipment. Microturbines are also lightweight-less than half the weight (and footprint) of traditional piston engines. There has been much ignorance about the environmental status of microturbines among people who should know better. Microturbines as not the engines that make airplanes loud.
Capstone turbines in Recla, Italy
If “Does it work?” is the most commonly asked question, then “How long will it last?” may be the second. One of the confidence builders for those who worry that their turbines, working well today, may become obsolescent tomorrow is a program like the Machinery Renewal and Upgrade (MRU) offered by Solar Turbines. The company has had its turbines in various industrial and onsite situations for 40 years; in that time, industry standards have advanced, and so have technologies.
With some machines and equipment their usefulness or effectiveness runs out, but the MRU can help older packages last longer, produce more, and reach the latest standards of performance, efficiency, safety, and compliance. The expectations of owners tend to rise as years of good service go by; with vehicles, mowers, and clothes, we buy new ones and think little of it. With products like turbines and microturbines (and their cogeneration systems), we talk about increasing production, service life, and return on investment. Upgrades can extend the life of the equipment, and match it to current power needs. Solar Turbines lists the helpfulness of their MRU program this way:
- increase production to meet growth in demand
- improve efficiency and output to meet changes in production demand
- maximize operations productivity
- address machinery obsolescence
- enhance reliability through system simplification
- leverage new technology to improve safety
- meet regulatory requirements
Replacing outdated controls would be one way to improve and save, especially in their ability to improve maintenance and troubleshooting. Adding an integrated fire and gas detection system or a DC (direct current) post-lube backup system can improve safety for technicians and protect the integrity of the equipment. A newer air inlet system can give much better particle removal; that would enhance efficiency and protect the turbine from internal damage. An engine power uprate, along with an upgrade to the driven equipment, would give increased flow and pressure for your compressor station or increased kilowatt output for your power station. If you converted to a dry, low-emissions system (such as SoLoNOx from Solar Engines) you would reduce NOx and CO emissions, to give you more permitting options and helping to improve local air quality. Compressor restaging would let you respond to changing gas conditions and restore top performance, with all the savings that would bring.
One More Success Story
Let’s go back to a real installation of microturbines to show how they can help the operation of buildings. Three microturbines (Capstone C65 ICHP) were commissioned four years ago for the Four Seasons Hotel Philadelphia. The eight-story, 364-room, five-star hotel uses a lot of energy each day for heating, lights, cooking, laundry, showers, swimming pools, and more. The management turned to E-Finity Distributed Generation to install a system to generate the hotel’s own onsite power.
The three microturbines’ combined heat and power technology allows the hotel to generate nearly 200 kW of electrical power (which takes care of 30% of the hotel’s overall electricity needs). The exhaust heat from the turbines is captured and heats the water for laundry and other operations. This CHP system provides 100% of the building’s everyday domestic water, and 15% of its heating needs. Among the results of this installation were 195 kW of electricity; electricity costs 20% less than utility power; a savings of $80,000 in the first two months of operation; more than 1.2 MM BTU per hour of recovered thermal energy; very, very low emissions (< 9 ppmv NOx at 15% O2); and quiet. Only 65 db at 10 meters-and a small footprint-the three microturbines with heat exchangers fit in a 37-square-meter space on the roof. Being quiet and using little space, the microturbines won the contract over reciprocating engine technology.
“Reciprocating engines have to be rebuilt at 22,000 to 23,000 hours,” commented Marvin Dixon, Director of Engineering at the hotel. “They have oil replaced regularly, consist of lots of moving parts, and have high vibration and noise. We can’t have noise at a hotel-that would be disaster. Four Seasons is a leader in the community, and accustomed to setting the standard for future generations. The microturbine installation is a step in the right direction in helping Philadelphia become a sustainable city.”Some “new technologies” for onsite power and achieving independence from traditional power sources that seem to be increasingly unreliable are not really new. Microturbines, turbines, and fuel cells have been feasible solutions for some years now, but it is the public awareness of their advantages that has been low. Microturbines have been a great success worldwide for a generation, but they have made only a promising impact in North America. There are still only a few manufacturers who have stayed the course, but they have proven reliability and can offer clear benefits in performance and cost, apart from their environmental diligence. They have improved in many ways, including their design and practical operation. Microturbines and turbines are past the starting line in the race for efficient, affordable onsite power, and they will be leaders soon, even if that means replacing some traditional systems en route.