Fossil fuels have traditionally powered modern societies since the Industrial Revolution and our present day well-being have been achieved through such fuels. They are, however, finite in nature and quite harmful to the environment since they are the main source of global warming. Japan, Germany as well as many other countries are highly dependent on the import of oil, gas or coal and have to pay the world market price. Unsustainable extractions have brought fossil fuels under constraint and countries which want to (partly) mitigate this issue, should start investing in renewable energies and re-arrange their energy generation sector to a more sustainable system. A functional mix of renewable and conventional power plants can reduce the need for fossil fuels in the electricity generation sector, thus lessen the carbon dioxide emission while securing supplies and stability. The main aim of this study is to investigate Japan’s potential for renewable energies and how to influence its energy generation sector with some take-away lessons from Germany. Qualitative and quantitative research designs were adopted to provide reasonable arguments to support the hypothesis that a fair share of its total (electric) energy demand could be achieved by capitalizing on renewable energy sources, while phasing out some old thermal power plants. A significant take-away lesson from Germany turns out to be adoption of more innovative energy policies and their constant upgrades. Patience with higher price of renewable energy sources during times that world oil prices significantly drops through political manipulation is another consideration.