Intelligent Tech Channels Issue 13 | Page 42

INTELLIGENT GREEN TECHNOLOGY Energy resiliency and security is a critical concern for the US Department of Defense, which needs to operate regardless of electric grid outages from cyber-attack, natural disaster, aging or lacking infrastructure, or equipment failure. The Department of Defense is also responsible for most of the US government fuel consumption and is one of the largest single consumers of energy in the world. As such, it has a vested interest in ensuring energy resilience, reducing consumption and controlling costs, and has pursued a variety of initiatives to reduce fuel needs and change the mix of resources that it uses. Military success and security in combat situations depends, in part, on safe and reliable access to fuel, which can come with a high price tag. Considering the price of fuel for forward operating bases, or the actual cost of buying, moving and protecting a gallon of petroleum, the costs of supplying battlefield generators with fuel has increased dramatically. This dependence and the threat it faces in forward operating bases led the US Army to seek both energy alternatives and resource management strategies. By transforming an independently operating system of generators into a demand managed microgrid, an Intelligent Mobile Power Distribution System provides power only where and when it is needed. This technology indirectly limits the risk that troops face to use, transport and store petroleum due to the decrease in fuel consumption. The system supports resiliency by providing adequate power to meet current energy demands, instead of inefficiently engaging all the generators continuously, which can reduce energy waste. Further, the system also uses intelligent load management technology to prevent grid collapse in the event of a generator fault. If one generator were to fail, the Intelligent Mobile Power Distribution System prevents a stoppage of energy flow by shifting demand onto the supporting generators, thereby providing a constant, safe supply of power. This system reduced fuel consumption more than 30% at the 42 Microgrids must be able to operate in parallel with the grid and as standalone electrical power systems that consists of multiple generating assets and storage sources supplying loads. forward operating military base. These and other successful early deployments helped advance and innovate on technology that is enabling new applications and driving value from microgrid systems. The control architecture is one of the most important elements of a microgrid system—it provides the brains behind the operation. In most current designs, the microgrid is tied to the upstream grid via a point of interconnection and is managed by local control of assets, which enables faster, semi-autonomous or autonomous control of the microgrid devices to better maintain operation within connected equipment limits. Nearly five years ago, early US Department of Energy smart grid demonstration projects showed the technology was feasible to manage the utility-scale storage system and integration of renewables. However, at that time, the controller was a customised solution. Today, an integrated, modular, distributed control architecture is becoming a reality. The easy configuration of the controller helps maximise the flexibility and scalability of the system while reducing engineering cost. When looking for a controller, functionality should coordinate automated system sequencing in response to user commands, system status, limits or faults. Additional control functions could also include active control, data logging, alarm management and processing, as well as built-in security measures. The costs to generate and store energy are decreasing, which is changing the nature of the utility grid from a centralised generation model to a distributed system of sources and loads. The electric system architecture is a system that allows consumers of large amounts of energy, to generate, store and manage energy usage. In effect, power generation is moving closer to the user due to the availability of microgrid system technology that can be leveraged with multiple types of renewable or distributed generation as well as the lower cost of energy storage. The drivers for microgrid systems have evolved and the technology is being used by a broader mix of industries and applications. Installing a microgrid is no longer limited to science projects and forward operating military bases. Microgrids can now be easily applied to facilities that already have solar, storage or other on-site generation sources. Excerpted from Microgrid evolution fuels smarter energy management by Bruce G Campbell, Jim Dankowski, Nathan Justice, Bob Kirslis, William Murch. Courtesy Eaton.  The control architecture is one of the most important elements of a microgrid system—it provides the brains behind the operation. Issue 13 INTELLIGENT TECH CHANNELS