FRANKFURT (Reuters) - Germany has secured the estimated 5,400 megawatts (MW) of back-up power it needs for the coming winter to cope with supply fluctuations and demand peaks, the energy regulator said on Monday.
Germany's power transport networks are not expanding quickly enough, requiring a reserve scheme that is administered by the Bundesnetzagentur agency, which oversees the stability of the grid in a bid to avoid blackouts and regional shortages.
"The reserve power requirement of 5,400 MW can be covered by plants that are signed up already," the agency said in a press release.
Germany shut 40 percent of its nuclear power station capacity in one go in 2011 after the Fukushima nuclear disaster in Japan, and has been investing heavily in renewable energy.
That has created challenges. For example, heavy production of wind power in areas where there is not enough transport capacity places stress on transmission grids and can require so-called re-dispatch - throttling production in some places, while revving up spare capacity in others.
This is a costly mechanism, but unavoidable in order to keep transmission lines balanced, as power cannot be stored.
The Berlin government had assumed enough new power transmission lines would be constructed by 2017 to transport, for example, wind power from the north to the industrial south, which previously relied heavily on nuclear energy.
But the construction has lagged expectations. Meantime, the share of renewable energy has reached 30 percent of output, and utilities are accelerating plant closures due to overcapacity and rock-bottom wholesale power prices. [EL/DE]
The regulator said in 2018/19 it would need 1,900 MW of reserve capacity, but only provided Germany's and Austria's networks - which currently are bundled in one zone without bottlenecks - were separated to allow better handling of excess power spilling into Austria.
Talks about this are ongoing, as governments, traders, neighboring countries and stakeholders in power transport and user industries differ on the pros and cons.
(Reporting by Vera Eckert; Editing by Mark Potter)