Think electricity and water don’t mix? Think again. Within the next year, a floating solar farm on Yamakura Dam in Chiba Prefecture will start providing enough power for nearly 5,000 households. It aims to be the largest installation of its kind in Japan, and the second-largest in the world.
The ambitious project is a collaboration between Kyocera TCL Solar and Ciel et Terre, a French manufacturer of floating solar support systems. Ciel et Terre pioneered its first mega floating solar project in July 2013, in Okegawa City, Saitama Prefecture. In an interview with The Journal, Hajime Mori, representative director, says Japan was a natural choice to launch the new technology because of its strong business infrastructure, abundant inland waterways, and attractive feed-in tariffs (FITs), which are rebates paid to renewable energy producers to stimulate investment in the sector.
In 2012, in response to the Great East Japan Earthquake and Tsunami of March 11, 2011, and the resulting shutdown of nuclear power stations, the Japanese government introduced one of the most globally competitive FIT schemes.
“Feed-in tariffs have proved there’s potential for 80 gigawatts of solar in Japan,” said Masaaki Kameda, secretary-general at the Japan Photovoltaic Energy Association, the country’s solar lobby, in a 2015 statement.
Though FITs have been waning in Japan and abroad in recent years, the rates still present a lucrative option for solar power producers, and Japan has proven itself a solar powerhouse. As of 2016, Japan ranked third in terms of solar power generation, behind Germany and China.
Solar still accounts for a meager portion of the country’s energy pie, but has attracted more investment than any other renewable energy source. According to a July 14, 2016 report in The Japan Times, 0.4 percent of Japan’s energy needs in 2012 were met by solar power; in 2015, the figure had risen to 3.4 percent.
The Ministry of Economy, Trade and Industry has fixed the country’s renewable energy target at 22–24 percent by 2030, as part of Japan’s commitment at the 2015 Paris Climate Change Conference to reduce greenhouse gases. The latest policy pronouncements also see nuclear energy accounting for up to 22 percent of the country’s power mix by 2030, with coal meeting 26 percent of Japan’s energy needs.
Though Japanese companies and the public sector continue to pursue projects in other forms of renewable energy, solar has emerged as the market favorite. Ciel et Terre’s Mori explained: “Solar energy is free, as we don’t need a big site preparation before installing a PV [photovoltaic] plant. With floating plants, we can keep the functions of ponds and reservoirs [as we] use the water’s surface. Floating systems are the best solution for the environment to create renewable energy.”
Kyocera TCL Solar is a special-purpose company set up in 2012 by Tokyo Century Corporation (then Tokyo Century Leasing Corporation) and Kyocera Corporation, in response to the expectation for increased solar demand in the wake of Japan’s revised FIT scheme. According to Ichiro Ikeda, general manager of the Solar Energy Marketing Division at Kyocera Corporation, as of January 31, the venture was involved in the operation of 62 projects totaling 225 megawatts in Japan. Speaking to The Journal, Ikeda explained that while Kyocera offers products for floating, ground-mounted, and rooftop installations, it began developing its floating solar business in 2014, due to a reduction in the availability of land suitable for large-scale ground-mounted projects.
One advantage of floating solar farms is the ability to locate them near power grids in densely populated areas. In the face of increasing urbanization, this aspect is key to delivering power quickly and efficiently to those who need it most. Massive ground-mounted installations are no longer feasible in most major cities. In Tokyo, for example, it would take about 60 square kilometers of land—equivalent to the area inside the JR Yamanote Line loop—to produce 1 million kilowatts of solar power, which is roughly the output of one nuclear reactor.
Installation of solar panels on water is also relatively quick and inexpensive compared with ground-mounted systems. No excavation is required, and there is no need for the costly earthquake-proofing foundation work mandated for all ground installations in Japan. In addition, floating solar plants can reduce evaporation and slow algae growth in freshwater.
A 2016 report from research organization Bloomberg New Energy Finance predicts Japan’s solar market will shift to rooftops in coming years. But, results of a study in Hyogo Prefecture show that solar panels on water can generate more power than rooftop designs. In a yearlong study completed in March 2015, local authorities concluded that solar panels installed on a reservoir generated 14 percent more power than those placed on the rooftop of an office building. This is probably due to the cooling effect water has on the panels.
Since the conclusion of the study, Hyogo Prefecture has launched at least 15 floating solar projects. “Our hope was that installations would expand if the prefecture took a lead and presented favorable results,” said Kenichi Tamura, an official in charge of the Hyogo research, during an interview with Bloomberg in June 2016.
Floating solar installations can be found throughout Japan, but Ciel et Terre’s Mori explained why the company’s projects are mainly located in the western part of the country, such as those in Hyogo Prefecture. “There are two reasons [the western area is preferred]: we can utilize many reservoirs in the area and take advantage of good grid connections. The north of the country is not so good due to heavy snow,” he said. Ciel et Terre’s engineers, many of whom are French nationals living in Japan, are currently exploring several options to lower the cost of the company’s floating system and adapt it to various environmental conditions.
Landlocked, sun-drenched Yamanashi Prefecture is also trying to attract solar projects. The prefecture has experimented with reducing or eliminating leasing costs for land used in ground-mounted solar installations.
For all its lures, many analysts still question the viability of solar power as an energy alternative. Solar power generation is contingent on favorable weather, and the annual operating rate of solar panels globally can be as low as 10 percent. The production costs of solar power are also higher than those of thermal or nuclear power, so widespread use of the energy source could lead to rising electricity charges for households.
But the individuals and enterprises involved in the solar business remain hopeful.
“With the recent reduction of feed-in tariffs and end of the solar bubble, we have seen media coverage on bankruptcies of solar-related companies; but market growth can continually be expected for solar energy itself,” said Kyocera’s Ikeda.
In the current market environment, which also sees increased competition from module makers in China, solar providers such as Kyocera and Ciel et Terre are shifting their business models.
Kyocera notes how the Japanese government is “working to promote proper operation and maintenance (O&M) for solar power plants and is considering making O&M services compulsory.” The solar module manufacturer has broad experience in this area of power management and will aim to expand its O&M capacity for both its own projects and those of other companies.
There is also an industry-wide shift from utility sales—where electricity providers such as Tokyo Electric Power Company, Inc. buy solar power to sell to their customers—to local consumption, where users buy power directly from solar farms.
And, as Kyocera’s Ikeda explained, this “self-consumption is ‘local production for local consumption,’ and we believe this is the ideal form for solar energy.”
Ciel et Terre’s Mori said, “We sell our electricity to utilities now, but are working on a self-consumption project aimed at local communities.”
“Because feed-in tariffs are going down, and 20 years is the only guaranteed duration of solar projects, we need a business [model] for the future beyond this time frame. I hope local organizations, such as those found in Japan’s smart communities [which integrate and utilize next-generation technologies], will come together to buy solar electricity. Floating solar is very suitable for these types of communities, where local people manage themselves.”
Kyocera, for example, is promoting the installation of small to mid-scale systems for self-consumption. Such systems combine solar power generation and power storage for maximum efficiency.
According to Ikeda: “New project implementation for the power sales business is expected to gradually decrease in the future. On the other hand, we expect that the market will shift from the conventional style of selling generated electricity to implementing solar power generation for self-consumption. In a market based on self-consumption, we believe that long-term reliability will become a stronger selling point for solar modules. If the modules can maintain high power generation for a longer period of time, the generation cost will become lower, and thus users will experience higher economic benefits.”
What’s clear is that Japan is not giving up on the potential of solar power. In the national tradition of technological innovation, it is perhaps not surprising that the Japan Aerospace Exploration Agency has been working since 2008 on its Space Solar Power Systems project. The goal: to transmit solar energy via microwaves from panels in orbit to Earth.