Is Your Back-up Power System Ready for an Earthquake?
A 2008 study conducted by the Working Group on California Earthquake Probabilities (WGCEP) found five California fault areas with a significant chance of a major earthquake (M > 6.6) in the next 30 years. These sites, all carrying probabilities greater than 1 in 10 and sometimes as high as 6 in 10, are at high risk for heavy seismic activity and the resulting damage from these earthquakes could be devastating.
With this in mind, forward-thinking companies are investing more capital in sophisticated techniques and technology to protect their existing power systems and backup power generators. Here are five ways companies proactively protect their business from seismic damage:
1. Select a location with low seismic activity - Although this may seem to be the most obvious step, companies should locate their facilities in areas that generally experience little to no seismic activity. Because many centers of business are located near the coasts or major fault lines, this may not be fiscally feasible. In that case, selecting a location away from major faults and their immediate surroundings is the best course of action. Once the general location is determined, more precise steps can be taken to further reduce location-related risk.
2. Soil and foundation analysis - Because many power and generator systems are built into the Earth, optimal soil composition is essential for reducing location-related risk. Depending on the makeup of the surrounding Earth, the soil can act as a strong natural dampener of seismic waves. Unweathered igneous rock provides the most solid foundation, and reduces the amount of amplification to a high degree. Volcanic and Mesozoic bedrock follows, with Quaternary sand, sandstone, mudstone, and limestone also providing acceptable levels of wave dampening. Muds, newer sands, gravels, silts, and artificial fill provide poor foundation, and can actually increase the amplification of seismic waves traveling through it.
3. Structural considerations - The ground motions created by earthquakes produce friction and displacement in structures and the contents within them. It is important when designing power infrastructure for earthquake resistance that all components of the building be comprised of adequate strength, with provisions made for varying motions and displacements. Housing for power systems and generators should have some flexibility to withstand heavier amplifications, but enough sheer strength to cancel out higher frequency waves. In addition, the resonance of the machinery within the housing should be measured and taken into consideration when constructing the housing so that amplification is not compounded by matching frequencies.
4. Vibration sensors - In generators specifically, the displacement of a bearing or other critical part could cause a reaction that shuts down the entire machine. Machinery should be tested ahead of time to find the frequency at which moving parts are displaced, and then outfit the housing and power system with sensors that can react and alter the operation of the machinery to adjust for increased vibration due to seismic activity.
5. Elastic support systems, spring elements, and dampeners - These devices, in a number of ways, work to reduce the amount of seismic force reaching the machinery itself. Elastic support systems provide flexibility and a smooth dampening of seismic waves in a manner that doesn't abruptly reduce amplification or displace moving parts. Spring systems absorb both vertical and horizontal wave output, depending on configurations. This allows the machinery to move with the frequency of the seismic wave, decreasing the amount of applied force to the machinery resulting from movement. Dampeners help eliminate the amount of stress applied to the aforementioned systems, preserving their integrity and longevity, and ultimately your critical power machinery.
These methods and technologies can provide a safe and secure setting for your power and generator systems. Visit globalpwr.com to see how our Project Management team can assist you with creating a secure generator system or power infrastructure. ABOUT GLOBAL POWER SUPPLY Global Power Supply is a leading supplier of equipment and technical solutions for critical project management and logistics. Global Power Supply offers solutions for critical facilities worldwide including buying, selling, and servicing critical power equipment, program management, asset recovery, and technical consulting.