Batteries are heart of ‘virtual’ power grid
French national grid company RTE has created a world first with ‘virtual power lines’ that will allow it to ‘transport’ up to 30% more energy without extra pylons being built.
Calling it the “first power grid to combine electricity and digital solutions” the RTE Ringo project will use a combination of new generation, more efficient substations and large lithium-ion batteries to create its virtual network.
Ringo allows RTE to cope with peaks of both production and demand and adapt its systems to cope better with renewable energy supply which is powerful but variable. It is set to start operation in 2020.
A farm of 20 wind turbines at full output can cause grid congestion as it is too much power to transport and this problem will grow in coming years as renewable energy increases.
Creating virtual power lines would allow excess production to be stored and give enough to power a town the size of Nancy (106,000 residents) in Lorraine.
RTE gave the example of a system where renewable energy can supply 130MW to a city where peak demand is 130MW but the existing power lines can only carry 100MW.
Ringo creates a virtual power line where excess output is stored in 30MW batteries at one end of the 100MW line and computers work out when excess supply – where the city cannot use all the power supplied – can be stored in another 30MW battery at its end.
When the city is at peak demand its 30MW battery supplies ‘virtual’ power to cope for up to two hours, the general length of peak demand.