The challenge as time goes by and that capacity retires is whether the back-up capacity is actually built," he said.
This latest delay could mean the government and public will pay through the roof for expensive back-up capacity to ensure the lights don't go out.
Bulk electricity storage is still in its infancy, and there are not enough mountains for much hydroelectric storage, so Germany still needs a big back-up capacity of conventionally generated power.
The new back-up capacity mechanism is in parallel with a programme that allows National Grid to ask contracted users – mostly factories – to reduce electricity demand when the system is strained.
Solar and wind are intermittent, so they are truly useful only if the power they produce can be stored; otherwise they need back-up capacity, typically from fossil-fuel sources.
But then another idea began to appeal, that of creating a North Sea offshore electricity grid to enable the growing number of windfarms around Northern Europe to tap into abundant Norwegian and Swedish hydropower resources, providing back-up capacity for otherwise intermitted renewable energy production.
At the same time, the report questions the storage capacity of E-vehicle batteries, because this is financially less attractive than back-up capacity from the grid.
It underestimates the supply demand balancing challenge, the need for back-up capacity and the role of nuclear power and interconnectors with Europe.
Although, in the short-run, this strategy may actually favor energy consumers (since prices are lower), the expectations of inactivity periods (regardless of whether they arise for strategic or market reasons) may negatively affect investment in back-up capacity, possibly leading to an increase in future prices (since less back-up capacity is available).
When the price paid to the electricity from EV batteries is considerable but is still less than the saving from reduced network loss and ESS back-up capacity, both the EV owners and system operators benefit from the optimal scheduling.
In particular, wind- and PV-based electricity generation heavily depends on weather conditions as this requires back-up capacity in case of under production and storage capacity in case of overproduction by the renewables.
