We wrote recently about how Sheffield University is using flywheels and batteries to balance grid frequency. This is becoming increasingly important as we feed energy from greener sources. Before we go into more detail, we will give you a clue. First we’ll tell you ‘frequency’ in its broad sense is the rate at which something happens. Then we will go into more detail.
Mains, or Utility Grid Frequency
We use alternating current outside of batteries. Grid frequency is the rate at which the alternating oscillations travel. This is not the same worldwide.
While much of the Americas use a frequency of 60 hertz, most of the rest of the world uses 50 hertz. It’s a long story how things ended up this way. We’ll ascribe it to history and move on to hertz.
What Hertz are in Electrical Terms
Hertz is a German family name. In electricity though, one hertz is equal to one second. Thus while American alternating electricity cycles sixty times a second, Europe’s is a little slower at fifty. German physicist Heinrich Hertz did not invent the measurement. But he was the first person to prove electromagnetic waves exist, and so the name perpetuates his memory.
Maintaining Consistent Grid Frequency
Frequency varies if there is an imbalance between supply and demand on a grid. It increases if there is an oversupply, and drops if demand is greater.
This plays havoc with electronics and causes electric light bulbs to dim and brighten. Behind the scenes, grid controllers are constantly keeping grid frequency within acceptable limits.
Utilities adjust the frequency of supply by taking small peaking stations on and off load. These smaller generators are traditionally hydro and gas turbines. Nowadays, we are using wind and solar to fine-tune grid frequency. This has only recently become possible thanks to advances in battery technology. These have finally enabled us to store significant amounts of electricity
Related
Connecting Flywheel Energy to the UK Grid
Basic Principles of an Alternating Current (AC)
Preview Image: Muizenberg Beach
