Even in one of the smallest countries in the EU, managing a grid is no easy thing. This is the task of Wärtsilä customer Elering, the Estonian transmission system operator (TSO), who is responsible of managing the Estonian electrical grid and operating it in a safe way.
A constant, real-time balance between supply and demand is an absolute must to keep the grid running and the power reaching customers without the frequency unbalancing. A TSO can, however, only control one side of the equation. While the energy supply has to carefully be managed by the TSO, in order to minute by minute meet the amount the country is consuming, power consumption fully depends on the end consumers and cannot be controlled. What happens if too many customers coincidentally decide to start using electricity at the same time or one of the main power plants suffers an unexpected malfunction? A blackout.