What is a Microgrid?
A microgrid manages distributed energy resources (DERs) and interconnected energy loads within a defined electrical boundary, such as a campus or business park. Distributed energy resources can include both traditional fossil fuel generators and renewable energy sources working together.
The key to an optimal microgrid design is compatible and stable grid components, controls, and monitoring products designed to efficiently manage distributed energy resources while balancing your demand needs and maximizing your economic benefits.
The utility grid comprises large-scale power generation plants, transmission, and distribution infrastructure that transmits electricity long distances. With aging infrastructures experiencing more power outages than ever - and rising energy costs - the demand is forecasted to outpace supply.
Advanced Microgrids take into account the energy, environmental, and economic constraints of the enterprise or institution - proposing the optimal arbitrage between the different opportunities: demand response, variable tariffs peak management, maximizing self-consumption, selling energy back to the grid, or supporting ancillary services (like frequency or voltage support).
A reliable, high-speed connection between distributed local and system devices is necessary to ensure stable, real time functionality. Standard industry protocols and topologies can offer the advantage of simple, external system integration. Information technology components such as fiber optic routers and industrial wireless modems connect the system over long distances - typically found in campus settings. Standard IT schemes complying with cyber security directives can be managed to minimize potential threats.
Schneider Electric's industry-leading Microgrid Control System integrates with your existing campus infrastructure to deliver a customized and scalable microgrid energy solution. Microgrids can track and forecast energy needs to ensure that comfort and productivity are efficiently and optimally maintained.
Today's energy managers need the ability to optimize the coordination of loads, generation, and storage. Advanced cloud-based information, communication, and control platforms are now available to achieve these goals. Weather forecast data, energy market pricing, load profiles, and forecasts of the consumer's energy needs are all crucial to predicting the best opportunities for energy consumption, storage, and production.
Real-time control and monitoring of all equipment should be easily accessible from a dynamic user interface that blends control and animated display for high operator efficiency, in both normal and critical scenarios.
Distributed Energy Resources (DERs)
DERs ensure energy independence and resiliency. The choice of DER components depends on many factors, such as: geographic locations (i.e., incorporating solar or wind), the local cost of fuel, and availability of incentives. Additionally, many microgrid installations use DERs that are already in place, which can be optimized through advanced controls. Microgrid designs should leverage the best options on a case-by-case basis.
The key to optimal management renewable source DERs, such as solar and wind, is forecasting their expected contribution to the microgrid - while also allowing for real time variations such as passing cloud cover or changing wind speeds.
Non-Renewables such as micro-turbines, fuel cells, and traditional diesel or natural gas generators offer a predictable supply of power. Schneider electric can review new and existing distributed generation, develop a feasibility study, and a microgrid architecture to integrate all of your DERs.
Storage systems using batteries or flywheels save excess energy produced by local DERs, or store grid energy at times when it is most cost effective. They complement intermittent energy sources like renewables by smoothing out the varying supply, and require replenishment to their available finite energy supply.
Combined Heat and Power (CHP)
CHP systems generate electricity and thermal energy in a single, integrated system by capturing heat that is normally wasted in conventional power generation. Captured heat can provide space heating, water heating, dehumidification, and even space cooling, through the use of absorption chillers. CHP systems provide power while grid-connected, and continue to provide power when islanded.
Electrical Distribution and Power Quality Engineering Expertise
Electrical system expertise is the most essential part of any microgrid solution. Experts understand how a microgrid can impact the electrical distribution system and that the solution must be designed to: anticipate transients and in-rush currents occurring between modes, maintain coordination of circuit breakers, maintain ground connections, avoid nuisance tripping, and protect for varying levels of available fault current. Islanded microgrids can exhibit more pronounced conditions due to the higher impedance of the DERs, thus microgrid solutions should only be delivered by experienced providers with deep expertise in power systems engineering, as well as power control.