Integration Costs of RES

Topical working group
“Integration costs of renewable energy sources”

Duration: March 2019 – July 2020

Renewable energy needs to become a major source of energy supply when aiming to achieve energy transition in both Germany and Japan. Among the various types of renewable energy sources, solar PV and wind power are expected to play a bigger role thanks to their large potential. On the other hand, these energies require technology to absolve fluctuating electricity output to make electricity supply stable. It means that cost of variable renewable energy (VRE) alone is not enough to assess its economic efficiency against other types of power generation technologies.

Since there are many types of integration technologies and its application method, which are being tested around the world, there is no established methodology to assess integration cost of VREs as well as appropriate choice and application of technologies. Under the current elementary stage of large-scale application of integration technology, discussion and mutual learning between Germany and Japan will have great value.

The GJETC will be moderating a panel of council members and external experts at the 7th Council meeting in Tokyo in September 2019 on the topic of “Integration costs of renewable energy sources”. The results of these inputs will then be summarized in a “Policy Brief”. It should select strategic topics related to integration cost of renewable energy sources and identify research questions for further cooperation.

Research questions

  1. What type of integration technologies are assumed, developed, tested and/or implemented in both countries?
  2. How does integration cost being evaluated so far (evaluation method and cost range)? Is the VREs already an affordable choice?
  3. What makes the difference of integration cost between Germany and Japan? Can we narrow the cost gap, and how to do so?


Integration Costs of Variable Renewable Energy Sources (Output Paper, 2020)
Authors: Yuhji Matsuo, Stefan Thomas, Andreas Löschel, Margaret Jackson

Extensive Introduction of Intermittent Renewables in Japan’s Power System (PPT, 2018)
Author: Yasumasa Fujii