This meter is monitoring the power
balance of the UK electricity grid. If the needle is
too far to the left, it means more generation is needed to meet
The meter actually shows the grid's
which is related to the speed of rotation of generators
all over the country. When there is too little power available,
the whole grid "slows down" and the needle moves to the
Why is this important?
It is important because it is possible
to measure this signal from any power outlet in the country.
This means that it is possible to design electrical appliances that
know the current imbalance on the grid. This is what dynamic
demand control is about.
The device to measure grid frequency
is very simple. Here at Dynamic Demand, we built (at very little
cost) a device that continuously monitors the frequency on the electricity
grid and updates this website with real-time data.
Dynamic demand appliances would react
to this very same signal. When the needle is to the left, they
would be more likely to switch off, reducing the load on the grid
and helping to restore the balance. When the needle is to
the right, they would be more likely switch on, using up the excess
power. Millions of such devices acting together would act like a
huge, fast-reacting back-up system.