Microgrid designs have evolved significantly in recent years, with the incorporation of information communication and technology (ICT) solutions such as artificial intelligence (AI) and machine learning (ML). A smart microgrid equipped with sensors and automation controls can efficiently perform load profiling and forecasting, generation management, load prioritisation, etc. Besides, if a microgrid is connected with an energy storage system (ESS), it can play a critical role in peak load shaving, grid balancing and managing the intermittent nature of renewable energy sources.
Smart microgrids
A smart microgrid is built upon the smart grid architecture, and contains all essential elements of a macrogrid. With the help of intelligent energy management software and hardware, a smart microgrid can balance energy supply and demand to maintain stable and reliable operations on a near real-time basis. Further, the use of ICT solutions such as sensors, and communications and automatic control enhances the energy management process and optimises system operations. It helps in intelligent and efficient electricity generation, management, distribution and consumption. A smart microgrid ensures maximum utilisation of renewable energy sources and other assets; helps in undertaking resource and load profiling, controlling and forecasting; allows load prioritisation as critical or non-critical; facilitates real-time data acquisition and monitoring of electrical and physical signals; assists in outage minimisation; facilitates fast response to network disturbances through the automatic connect/disconnect of system components.
AI and ML have emerged as new features of smart microgrid designs. The use of AI and ML in microgrids helps in identifying patterns in information and developing solutions without supervision. The country’s first solar-powered smart microgrid was set up in Rajasthan by Gram Power. It supplies electricity to rural villages and urban consumers at a low cost.
Microgrids with control systems
Broadly, the control system of a microgrid comprises a microgrid central controller (MGCC) and field control units (FCUs). The MGCC is the main control centre, which manages power production and consumption autonomously or based on commands from network operators. It unifies microgrid data from a wide range of field devices. The MGCC also provides human machine interface service for local microgrid management, as well as interfaces with microgrid cloud applications for remote management. FCUs are linked directly with local components. They monitor and measure local information on a real-time basis and send it back to the MGCC. A microgrid’s control system can be equipped with a supervisory control and data acquisition (SCADA) system. SCADA is used for data acquisition, monitoring and procedure control for spot devices. It can operate a computer-based production control and an automated despatch control, thereby enhancing the efficiency of power despatch. Further, a microgrid equipped with a control system is capable of coordinating the energy flow within a power network to ensure efficient operations. The control system can manage industrial and residential loads, ESS, renewable and conventional power generation in order to drive system efficiencies. It also helps in maximising fuel savings by ensuring the optimum utilisation of renewable energy sources, and implementing smart control schemes and algorithms.
Microgrids with energy storage
ESS helps in realising the full benefits of microgrids. In ESS, electricity generation is decoupled from energy demand. When production exceeds consumption, the energy is stored to meet the power demand when needed. ESS-equipped microgrids offer cost-effective solutions to lower the overall energy costs and improve the grid’s resilience. Such solutions present a cleaner alternative to the carbon-emitting diesel generators. Energy storage also provides additional revenue to utilities from ancillary services such as frequency regulation, energy arbitrage, spinning reserves, black-start processes and demand response. The various ESS include batteries (lithium-ion, sodium-ion, etc.), pumped hydro storage, compressed air energy storage and high speed flywheels. Plug-in hybrid and electric cars also provide feasible energy storage for balancing smart grids without any extra cost. The deployment of storage technologies depends on their cost, energy density and discharge life cycle, among other things. For optimal operations, the type, configuration and impact of the ESS need to be considered.
Net, net, a number of technology solutions are available for improving the operational efficiency of a microgrid. For best results, it is essential to choose a technology based on the cost-benefit analysis, keeping in view the needs and requirements of a particular region. With the integration of IT and OT solutions in a microgrid, it becomes essential to deploy a robust cybersecurity mechanism to maintain a stable grid. It is essential to refine interconnection policies, streamline microgrid policies with EV policies and the deviation settlement mechanism, and encourage end-consumer participation.
