Inside edgeFLEX

Today: SWW
Beer, water and power – the role of energy supply in Wunsiedel

If I told you that the German trial site is doing testing of voltage control and reactive energy management, you would for sure say: “Sounds interesting… But what does this mean?” So let’s take a tour into the mysterious, complex and not so far away realm of electricity grids, where voltage and power rule alongside each other.

Let’s start by explaining what voltage is. Picture a water tank. To this water tank there are pipes connected to, which fill it to keep it to a certain level. Now you open the tap at the bottom of the tank and water comes out. The pressure of the water streaming out is comparable to the voltage in an electricity system.

If there is not the right water pressure – meaning that not enough or too much water leaves the tank – the system will collapse. You see, it is very important to keep the voltage within defined boundaries in order to maintain operational viability. Voltage control, thus, denotes actions performed for maintaining the voltage level of the system within these boundaries. In every realm there are rules.

As for the reactive power – one can look at it as a glass of fresh beer (not even science is safe when it comes to Germans’ favourite drink). The liquid itself, the strengthening hop juice every hero seeks, is the real or active power. The foam on top is a natural part of the beer but one cannot drink nor gain satisfaction from it. This is the reactive power – part of power generation, but not usable. However, something useless at first sight turns out to be necessary: it is essential for creating the electric current itself and keeping the electricity grid stable.

But as described above the electricity grid has its boundaries. Thus, reactive power needs to be reduced to a minimum which grants the stability of the grid as well as meets the demand of consumers at the same time.

But where is the connection to edgeFLEX? We build onto the previously implemented innovative energy management system infrastructure, laid out during the GOFLEX Project. This gave us the first foundation for enhanced control possibilities. During edgeFLEX, a new trading platform was established additionally enabling to host the existing capabilities alongside state-of-the art electricity monitoring devices, the edgePMU developed for this purpose within the project. The combination of new technologies in the German trial will be used to control voltage levels by monitoring power events. To do so, they send indications to the power trading platform to help reallocate energy in what is called flexibility. This helps us to manage the reactive power demand and to avoid costs by using renewable and decentralized energy units. So, basically, we combine voltage control, flexibility aggregation and reactive power management to improve the stability of the grid and to be as cost effective as possible.  

Evyatar Littwitz and Sophia Rohbogner