PV Expo and the wider Smart Energy Week concluded in Tokyo last week. It revealed ambitious plans for solar and energy storage installations in Japan, including creative approaches to the severe lack of space for new facilities, which should bring plenty of opportunities for domestic and international players.
Solar and renewable energy in Japan has often been described as “in transition” over the past few years. Solar installations have remained flat at 5 GW to 6 GW per year, while falling feed-in tariffs and a lack of suitable land for new large-scale solar installations have left many wondering what will happen next for Japan.
The country aims to use at least 36-38 percent of renewable energy sources in its energy mix by 2030. An opening-day presentation by Kazuya Inoue, director of climate change policy at Japan’s energy ministry, said this would require at least doubling Japan’s cumulative solar capacity and significantly increase the number of installations in the second half of this decade. Inoue noted that SM is “committed to solar energy,” and its calculations show that renewables could cover at least 1.8 times Japan’s total electricity needs — meaning much remains untapped. In response, the MoE is providing 20 trillion yen ($151 billion) in funding for various renewable energy, energy storage and carbon reduction projects until 2030.
With little land left suitable for large-scale solar power plants, Japan’s solar power policy is shifting toward rooftop and commercial solar power models. Many Japanese companies have set themselves targets for carbon dioxide emissions and want to clean up their energy with the help of solar power purchase agreements. Tokyo-based analysts RTS Corp. explained that high energy prices and subsidies available for solar PPA installations make this model particularly attractive at the moment.
RTS also said it expects Japan’s market for ground-mounted solar to shrink as residential electricity grows. It noted that experimental systems requiring solar power for all new buildings are being trialled in the Tokyo and Kawasaki areas and are likely to be rolled out in the near future.
Japan has also seen a few early installations combining solar energy and farmland, but opinion is divided on whether this agrovoltaics approach will serve as a solution to the land shortage for solar projects. According to RTS, Agrivoltaics in Japan is likely to see some growth in the years leading up to 2030, but the Ministry of Agriculture is not well prepared, and the development of a real market will require extensive reform of land use regulations.
No more PERC?
Chinese cell and module manufacturers dominated much of the PV Expo hall, eager to showcase their latest products to a market traditionally interested in the latest technology. Each of these companies said plans are already well underway to phase out PERC cell production entirely by the end of 2024 or even sooner.
And all the trades were on display this week, most going the simplest route to the TOPCon version to gain efficiency. Trina Solar and JinkoSolar were among the companies that confirmed plans to stop producing PERC altogether. And DAS Solar, which uses 30 GW of TOPCon cell capacity and plans to expand to 40 GW this year, said. pv magazine this “is just the beginning for TOPCon” and is expected to reach 26% production cell efficiency in 2024.
However, others are looking further into the future and the even higher performance levels that could be achieved with heterojunction and back contact technologies. Manufacturers Huasun and Risen presented their latest heterojunction products, the first of which aims for an average production cell efficiency of more than 25% and plans to expand its capacity to 40 GW by 2025.
Longi Solar also had its latest hybridized back-contact products, and Aiko Solar introduced its latest All-Back-Contact product, which it will introduce to the rooftop market this year and expects to be able to reduce costs sufficiently for the large-scale segment in the next few years, as well as achieve better than 27% module efficiency.
Electronics giant Sharp—seemingly the only Japanese company to display any type of PV module at this year’s show—showcased its multi-junction gallium arsenide-based cell with an efficiency of more than 30%. Currently more than 100 times the cost of a typical silicon cell, it’s a long way from being attractive as a power source for anything other than space travel. Nevertheless, the company introduced a Toyota car covered in these cells, which added an impressive 860 W of solar power to the vehicle’s body, which the company says can run up to 50 kilometers without recharging.
Sharp also says it is working with the New Energy and Industrial Technology Development Organization (NEDO) to bring the cost of these cells down to earth. They’re developing a reusable platform and broader processes to cut over a third of the overall cost, but don’t expect to see them through the roof anytime soon.
Photo: pv-lehti / Mark Hutchins
Japan, like many other markets where the share of renewable energy is growing, has realized that it needs to do a lot of work on its power grids in order to deliver all this clean energy when and where it is needed. And the Smart-Grid Expo was a place where well-known Japanese brands could shine better. Mitsubishi Electric had a range of software on display that demonstrated its ability to manage large power grids by combining data from several small utilities into a virtual power plant.
Sharp, along with China’s Growatt and Sungrow, also showcased electric vehicle chargers and previewed vehicle-to-grid and vehicle-to-home approaches, which use the car’s battery while plugged in to maximize solar power consumption from a rooftop installation. , or many are connected to each other so that this scales to the entire area. It’s an approach that these companies expect to gain a lot of traction in Japan in the coming years, especially on the housing side.
