Grid controllers are systems that manage the flow of electricity across a power grid. They ensure that the supply of electricity matches the demand, helping to maintain a stable and reliable power supply. By monitoring various factors, such as energy production and consumption, grid controllers can make real-time adjustments to prevent outages and optimize performance. These controllers play a crucial role in integrating renewable energy sources, like solar panels and wind turbines, into the grid. They help balance the variability of these energy sources with traditional power generation, ensuring that electricity remains available even when renewable output fluctuates.