In many cases, a simple change in schedule is enough to help balance the grid and, at the same time, make use of the variable price tariffs commonly available in many countries. Private households with hot-water tanks can time the heating of the water to occur during the night hours when the demand is lower.
In a smart system, this can mean a few seconds here and a minute there, in a way that keeps the grid in balance through the night. The heaters are also controlled with an accuracy of seconds or minutes to keep the grid frequency stable. The water will be hot in time for the morning shower, and there is no inconvenience at all to the inhabitants.
Electric and hybrid cars are becoming more and more common. They can also play a part in a flexible energy system. The battery of the car needs to be charged and ready to go in the morning. But does it matter whether it is charged before three in the morning or at five a.m.? Probably not, so the charging can be slowed down or interrupted for a moment if the electricity is needed elsewhere.
In the future, it will be possible to create a two-way connection between the car and the grid, so that electricity can also move from the car to the grid, when the car is not needed. This will turn electric vehicles into a grid-connected storage solution that can be used for grid balancing purposes but also to balance consumption peaks.
Staying warm while balancing demand peaks
Heating is another component of a flexible energy system. A house is, in essence, a heat storage. If it is heated with electricity, cutting the heating off for a few minutes will not drop the inside temperature but it can help balance the total consumption vs. production of the energy system. These kinds of short-term adjustments can make a significant difference in maintaining the stability of the grid and ensuring that the consumption and production are in balance.
Demand-side flexibility can also be applied in district heating. Heating plants must anticipate demand peaks such as the morning when everyone wants to shower at the same time. If the demand peak is high, production with higher emissions may be needed to cover it and a back-up plant has to be started up.
Flexibility keeps the grid healthy
In the Nordics, the electricity grid is built so that it can handle the capacity needed to heat homes in the winter. In warmer countries the infrastructure is not always as developed, and extreme weather phenomena such as exceptional cold spells can cause heavy strain on the grid. Electricity grids also need flexibility to operate optimally, and at some point, the capacity of the grid may reach its limits. In such situations, flexibility-improving solutions may be more sensible than increasing grid capacity to answer occasional demand peaks.
The absence of flexibility has, in some countries, led to brown-outs: when traditional production facilities’ or power line limits have been exceeded, electricity has been cut off completely from some areas to keep the entire system from collapsing. This is naturally something we do not want to see. While flexibility-enhancing solutions help us cope with such situations, they also help us prevent them by allowing us to have more renewables in the grid.
So when should I charge my car?
Energy companies, such as Fortum, have online services in which people can monitor their energy use and the price they pay for it. In some countries, the rates vary throughout the day and night, and night prices are generally cheaper as there is less demand. Some smart internet connected systems can already be used to control hot-water tanks or heat pumps and schedule their heating. Electric vehicle charging is also a major contributor to energy consumption flexibility, and smart concepts exist to control it remotely, as well.
Fortum Spring already has in use a smart charging system for electric cars at the company’s head office. The system is also piloted in Norway with Fortum Consumer solutions, with which Fortum has also carried out a heat pump pilot project in Sweden. In the future, Fortum and Fortum Spring will focus on consumption flexibility through partners. This means that we will provide optimisation services to, for example, heater manufacturers.
We at Fortum continue to develop flexibility solutions that provide the needed balance in the energy system without causing inconvenience to people or households. Join us in creating a more flexible, resilient and reliable energy system!