This special interest group is for professionals to connect and discuss all types of carbon-free power alternatives, including nuclear, renewable, tidal and more.


100% renewable energy in Japan

image credit: Global Pumped Hydro Atlas
Andrew Blakers's picture
Professor of Engineering, Australian National university

Andrew Blakers is Professor of Engineering at the Australian National University. He founded the solar PV research group at ANU. In the 1980s and 1990s he was responsible for the design and...

  • Member since 2021
  • 132 items added with 12,661 views
  • Mar 14, 2022

A recent study has shown that Japan has 14 times more solar and offshore wind resources than needed to supply 100% renewable electricity. It also has vast capacity for off-river pumped hydro energy storage to balance variable solar and wind.

Low-cost solar photovoltaics and wind offer a reliable and affordable pathway to deep decarbonization of energy, which accounts for three quarters of global emissions. However, large-scale deployment of solar photovoltaics and wind requires space, and may be challenging for some countries with dense population and high per capita energy consumption.

A recent study investigated the future role of renewable energy in Japan as an example. The study comprised an hourly energy balance model of a hypothetical 100% renewable Japanese electricity system using representative demand data and 40 years of historical solar and wind meteorological data.

Pumped hydro energy storage, high voltage interconnection and dispatchable capacity (existing hydro and biomass and a few percent of hydrogen energy produced from curtailed electricity) were included to balance variable generation and demand. Differential evolution was used to find the least-cost solution under various constraints.

Offshore wind is important in regions such as Japan, Korea, the Philippines, northern Europe (bordering the North Sea) and northeast USA. These regions have high population density but access to vast areas of windy seas. Co-location of solar with agriculture is also important. “Agrivoltaics” involves shading around 10-20% of crops and pasture with widely spaced solar panel rows. While some crops such as rice respond negatively, many others respond positively or are neutral to the shading. The solar electrical output amounts to a second cash crop for the farmer, similar to co-location of wind turbines in farmland. In Southeast Asia there is vast capacity for floating solar on calm tropical seas.

Solar and wind are being installed at scales above 200 GW per annum and doubling every 3-4 years. Prices continue to fall and are converging upon global norms, as is usually the case with very large industries.

In our study of Japan, we found that the levelized cost of electricity from a solar/wind dominated system is in the range US$86-110/MWh. These costs can be compared with 2020 average wholesale prices on the spot market in Japan of US$102/MWh. Cost of balancing 100% renewable electricity in Japan (included in the preceding figures) ranges between US$20–27/MWh.

In summary, Japan can be self-sufficient for electricity supply at competitive costs.

Jim Stack's picture
Jim Stack on Mar 15, 2022

Andy, Thanks Japan is showing the way for all the other countries. I hope all the other leaders want to show they are as smart and follow their lead. A few are trying but just don't put enough importance on being over 100% renewable. I have done it on my home . I made ever company I worked for much more efficient but they just don't get much done on their own. What will make them wale up and get moving on their own ?

Nathan Wilson's picture
Nathan Wilson on Mar 15, 2022

We can certainly expect the fossil fuel importing countries to lead the way on decarbonizing their electricity (rather than coal giants like Australia and Germany).  However, Japan is far behind their non-fossil producing peer, such as France, Sweden, and Switzerland.  The common theme is that countries that embrace nuclear energy have easily decarbonized their grids, whereas countries that reject nuclear remain addicted to fossil fuel, all the while making promises of grand renewable visions.

Andrew Blakers's picture
Andrew Blakers on Mar 15, 2022

Actually, the global renewables pathfinder is Australia. The National market is sitting at 35% renewables, and tracking towards 50% in 2025. South Australia is tracking towards 100% solar/wind in 2025. Australia has zero nuclear.

Joe Deely's picture
Joe Deely on Mar 16, 2022

However, Japan is far behind their non-fossil producing peer, such as France, Sweden, and Switzerland.  The common theme is that countries that embrace nuclear energy have easily decarbonized their grids,

Let's not forget another country which has embraced nuclear - Brazil.  Plus, unlike France, Sweden and Switzerland nuclear has not declined in Brazil in recent years.

Andrew Blakers's picture
Andrew Blakers on Mar 17, 2022

Facts on the ground: according to the World Nuclear Association, global nuclear generation declined over the past decade.

Andrew Blakers's picture
Thank Andrew for the Post!
Energy Central contributors share their experience and insights for the benefit of other Members (like you). Please show them your appreciation by leaving a comment, 'liking' this post, or following this Member.
More posts from this member

Get Published - Build a Following

The Energy Central Power Industry Network is based on one core idea - power industry professionals helping each other and advancing the industry by sharing and learning from each other.

If you have an experience or insight to share or have learned something from a conference or seminar, your peers and colleagues on Energy Central want to hear about it. It's also easy to share a link to an article you've liked or an industry resource that you think would be helpful.

                 Learn more about posting on Energy Central »