In the Electricity generation and demand graph, the graph of power generation from each different source for a selected time frame can be viewed for each of the 10 grid operator or the entire country.
This time we will be finding the date and time when renewable energy hit its highest proportion of the energy supply in 2017.
The figure above shows the energy supply and demand of Kyushu, which is said to have a relatively high renewable energy proportion, on the 14th of April 2017.
On this day, at 11:00 the renewable energy proportion of demand records a share of 86.9%, the highest value for the first half of 2017.
Looking at the relevant parts of the graph, Renewable source are producing 6,782MWh compared to the demand of 7,804MWh. Around this time period, it is evident that power lines and pump hydro systems are being used to adjust the excess electricity generated. (Purple and light blue bars that go lower than 0)
However looking at the nationwide graph, the maximum of the first half of 2017 occurred at 11:00 on the 30th April, national holiday, where the renewable energy accounted for 52.4% of energy demand.
It is possible to use the search function to find the maximum and minimums. Please look up data on your own region or areas of your research.
 During the time of this writing (January 2018), only data from April 2016 to Septemper 2017 has been released, thus only data from this time period can be displayed.