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1 August 2013

Cost optimalexpansion of renewables in Germany

A comparison of strategies for expanding wind and solar power in Germany


Germany‘s energy transition has to be affordable. In view of the continuing expansion of renewables, a number of questions arise that are crucial for future costs of our power system:

  • Where should wind turbines and solar arrays be built – in the best sites or close to consumers?
  • Does the expansion of renewables have to wait for grid expansion?
  • What will happen if PV arrays with battery storage breakthrough on the market, and will we still need grids?

Agora Energiewende had Consentec look into these questions with the support of Fraunhofer IWES.
A number of scenarios were investigated up to 2033 based on the German Network Agency’s lead scenario for the Grid Development Plan 2013. In addition to the cost of renewable energy, the cost of grids, storage, and conventional power generation was taken into consideration.

The findings are quite interesting and offer some new and surprising insights even for experts. To facilitate further discussion, the assumptions used are published on the website.

Key findings

  1. Policy makers have a large scope of action in designing policies for the regional distribution of onshore wind and photovoltaics.

    Regional distribution of this renewable energy has little impact on the total cost of power supply.

  2. Finding the right balance is important in expanding offshore wind power.

    To promote technology development and reduce the cost of electricity for consumers, expansion should be continued, but on a lower level than current plans foresee.

  3. Grid expansion is an important prerequisite for the Energiewende.

    Solely in terms of cost, a few years of delays for the additional transmission lines foreseen in the German Grid Development Planning act would not be critical. Further expansion of renewables does not have to wait for these new transmission lines.

  4. A strong focus on battery storage systems combined with photovoltaic is currently not desirable.

    Only if cost of such systems drop by 80 % in the next 20 years would a renewable expansion path focusing on photovoltaics + storage be an economically viable option.

Bibliographical data

Bernd Tersteegen, Carsten Pape
Publication number
Publication date

1 August 2013

This publication was produced within the framework of the project Optimising the expansion of renewable energies.



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