Generator Reliability – Generac Generators
Third party studies have found the average standby generator system within the market has a reliability of around 99 percent. Generac Power Systems believes this level of generator reliability is unacceptable. It has been Generac’s mission to design standby generators that exceed the market norm for reliability. Generac has addressed the following key reliability issues through superior product design.
Lack of Maintenance
Generators must be maintained to remain reliable (batteries, belts, hoses, fluids, etc.). However, many customers lose sight of this reality as time passes. Generac’s advanced generator controls include predictive maintenance algorithms that warn the user when maintenance is required. Competitive systems in the market don’t include this feature.
Sensors, Connection and Circuit Board Failures
Generators are a long-life product making age deterioration the main failure mode. An area of significant concern is the oxidation of sensor connections resulting in intermittent or false sensor reading. Generac’s advanced generator controls use a sealed wiring harness to limit this failure. In addition, the sensors utilize a premium 4-20 mA signal common in mission critical process control. This type of signal is more accurate, less sensitive to corrosion and resistant to electrical noise. Current industry standards for on-site generators use a less expensive voltage-based feedback. Circuit board design can be a significant element in generator system reliability. Generac uses an integrated approach for generator control, combining multiple control functions into a single, secure, alldigital controller. This reduces component count and interconnected wiring resulting in increased reliability. Generac’s advanced controls use surface mount technology for vibration immunity and are sealed inside an aluminum casing for environmental and electrical protection. Many generator controls available today are multiple devices with non-sealed boards and vibration sensitive components.
Fuel Failures
Though smaller kilowatt (kW) applications are dominated by natural gas powered generators, diesel generators are the industry standard for applications larger than 150 kW mainly due to their lower capital cost. Though cost effective, diesel does not come without reliability issues. A typical generator application may take 10 years to empty its diesel fuel tank. This demands that customers perform generator fuel maintenance; if not aggressively maintained, it will become unreliable. The other significant failure mode is running out of fuel. When an area-wide outage occurs (hurricane, flooding, ice storms or grid failures), refueling the generator becomes extremely difficult.
To address these issues Generac has developed two alternatives to the standard diesel approach. To minimize the amount of on-site fuel that must be maintained while maximizing the generator’s run time, Generac has applied its Bi-Fuel™ technology to standby powergeneration. Bi-Fuel engines simultaneously run on diesel and natural gas. In this configuration, a diesel engine will operate on 25 percent diesel and 75 percent natural gas, extending the run time of on-site fuel by a factor of four. The Bi-Fuel configuration also has the ability to automatically revert to 100 percent diesel operation in the unlikely situation of concurrent electric and gas service interruption.
Though smaller kilowatt (kW) applications are dominated by natural gas powered generators, diesel generators are the industry standard for applications larger than 150 kW mainly due to their lower capital cost. Though cost effective, diesel does not come without reliability issues. A typical generator application may take 10 years to empty its diesel fuel tank. This demands that customers maintain their diesel fuel; if not aggressively maintained, it will become unreliable. The other significant failure mode is running out of fuel. When an area-wide outage occurs (hurricane, flooding, ice storms or grid failures), refueling the generator becomes extremely difficult. To address these issues Generac has developed two alternatives to the standard diesel approach. To minimize the amount of on-site fuel that must be maintained while maximizing the generator’s run time, Generac has applied its Bi-Fuel technology to standby power generation.
Bi-Fuel engines simultaneously run on diesel and natural gas. In this configuration, a diesel engine will operate on 25 percent diesel and 75 percent natural gas, extending the run time of on-site fuel by a factor of four. The Bi-Fuel configuration also has the ability to automatically revert to 100 percent diesel operation in the unlikely situation of concurrent electric and gas
service interruption.
Removing Single Point Failures (N+1)
Though a single engine generator can be made more reliable through good design, it still has many single point failure modes (batteries, starters, solenoids, belts, hoses, etc.). To significantly improve the reliability of the backup power system, the system cannot rely on any one single generator. Just as an HVAC or UPS system uses a modular approach, so must the backup power system. This is accomplished by using multiple generators operating in a
paralleled configuration resulting in power system redundancy for the system’s most critical loads.
Parallel power solutions have always offered the standby power generation marketplace significant advantages. However, the implementation of these solutions has been limited to mission critical applications and large kilowatt projects. This is largely due to the constraints in implementing traditional paralleling solutions. These constraints include costs, space, issues of
single source responsibility and a significant level of complexity. To assess the benefits of parallel generation while removing the cost and complexity limitations, Generac has integrated the generator paralleling into the genset package.
Generac’s Modular Power System (MPS) is a completely integrated, UL listed, paralleled power solution.The MPS solution utilizes a paralleling switch mounted inside the generator connection box and an integrated digital controller. This approach achieves all of the simplicity and cost points of single engine solutions while maintaining parallel generation benefits: redundancy, scalability, flexibility and serviceability.
Total Solution Approach to Reliability
Generac doesn’t look at generation as a capital equipment supplier but rather as a power solutions supplier. With that in mind, Generac strives to address all elements of on-site power production reliability.
To learn more about Generac generators and their reliability – in New England contact ASNE at sales@asne.com or 88-890-9886 or outside of New England visit the Generac web site to find your local Generac expert.