Japan's Tipping Point: Renewable Energy from Solar and Geothermal

by Mark Pendergrast

This is my second post in a series of three about the state of Japan's renewable energy efforts, which are vital to prevent further climate change and to wean the country from fossil fuel and nuclear power. In the previous post, I covered the public-health impacts of climate change and explained why Japan is a good indicator of whether countries will be able to act quickly enough in the face of these threats. Japan's reliance on imported fossil fuels gives it a good reason to invest in alternatives, and its technological sophistication should help it develop renewable-energy technology. I investigated Japan's use of renewable energy for my recently published book, Japan's Tipping Point: Crucial Choices in the Post-Fukushima World, and what I found was that the country has made progress in some areas but hasn't realized much of its potential.

I arrived in Japan two months after the March 11, 2011, earthquake and tsunami killed over 20,000 people and caused a meltdown at the Fukushima nuclear reaction. Until then, Japanese leaders had been planning to build 14 more nuclear power plants that, together with the 54 then-active plants, would provide half of the country's electricity. Now those plans have been scrapped. But what is the current state of Japan's renewable energy efforts? Here I will cover solar and geothermal energy.

Solar Photovoltaic Panels
Until July 1, 2012, photovoltaic panels will be the only form of renewable energy that receive a federal subsidy and feed-in tariff, so they offer the most hopeful outlook in Japan. Yet even here, Japanese policy has been inconsistent. In 2005, Japanese firms dominated the global solar panel industry, producing about half of the world's supply. That year, the federal government stopped subsidizing PV panels, and the Japanese market subsequently dwindled, just as Germany, China, and the United States were coming on strong, each with subsidies of varying amounts. By 2009, when its subsidy was belatedly renewed, Japan had fallen from prominence in the field, supplying about a tenth of the world's panels. In a list of the top 15 solar panel manufacturers in the world, published in 2010, Japanese companies showed up in the tenth and eleventh spots.

The good news is that PV panels are getting cheaper for everyone because of mass production, with the price cut nearly in half over the past two years. And Masaaki Kameda of the Japan Photovoltaic Energy Association told me that the Japanese residential market is booming, with over a gigawatt of PV power installed on rooftops in fiscal 2010. Nonetheless, only 40 percent of the panels produced in Japan are used in-country. Photovoltaic currently supplies less than half of one percent of Japan's electricity.

Solar Hot Water: A Besmirched Technology
Even though producing hot water from sunshine is a well-established, proven technology that (ignoring subsidies) costs less than PV panels, it is unpopular and has a terrible image in Japan. Thermal solar sales swelled in the 1980s, following the second oil crisis, spurred by low-interest government loans. But aggressive salesmen gave the industry a bad name. Because of the moderate climate in all but the northern island of Hokkaido, many consumers opted for an inexpensive system that uses only water. As the pipes are heated by the sun, the hot water flows into a tank on the roof and can then be drawn into the house by gravity. On nights when the pipes might freeze, owners must drain the water and refill it the next day. Unscrupulous salesmen could easily spot the rooftop tanks and would tell homeowners that their system needed maintenance and special chemicals.

In addition to such scandals, the pipes for the hot water systems began to crack and fail in 15 years or so, and by that time many manufacturers were no longer in business. From 2002 to 2005, the Japanese government gave subsidies to both solar hot water and PV panels but then terminated both of them. Now PV panels are an upscale status symbol, while people don't want an ugly tank on their roof.

There are three types of solar hot water system. The down-scale water-only systems cost a bit over $3,000. Others use a form of anti-freeze in the rooftop panels that passes through a heat pump in the house, where the water is heated. A small pump circulates the cooled anti-freeze back to the roof. These units cost about $10,000 without subsidy. Finally, there are systems made by OM Solar that are more expensive and can only be installed in new homes. This third approach heats and circulates hot air that provides radiant floor heat as well as hot water.

In Japan, businesses are pushing all-electric "eco-homes" featuring the EcoCute that produces hot water from the air via a heat pump and is indeed relatively energy efficient. But EcoCutes cost about $9,000, and they add more than $60 to the monthly electric bill, whereas hot water is essentially free once a solar thermal system is in place.

The Tokyo Metropolitan Government has given subsidies for solar hot water for the last two years, with few takers. For fiscal 2011, Tokyo is sharply increasing the subsidy, but Shoji Kobayashi, the head of Tokyo's Renewable Energy Policy Division, isn't sure it will help. "People think the hot solar water panels are ugly, even in a hybrid system with PV panels," he told me. I said this was crazy - the anti-freeze type panels look as slick as those that generate electricity. That doesn't matter. "People associate them with the old style," Kobayashi concluded.

Geothermal: Potential Unrealized
Japan exists because it is the site of clashing tectonic plates, so magma spurted up from volcanoes and other land buckled and rose as one plate dove under another. That's why there are 120 active Japanese volcanoes, 28,000 hot springs, and major periodic earthquakes. Like Iceland, Japan has enormous potential for geothermal energy. But unlike Iceland, which gets a quarter of its electricity and nearly all of the heat for its buildings from the earth's vents, Japan derives only 0.2 percent of its electricity from geothermal plants at 18 sites.

There are three reasons. First, 80 percent of the potential sites are inside Japanese national parks, mostly in the northern Tohoku region, Hokkaido, and a bit on Kyushu to the south. Second, there is fierce resistance from owners of onsen (hot springs) resorts, who fear that nearby geothermal plants would deplete their hot water. And third, it is expensive and time-consuming to build geothermal plants. It costs around $3.5 million and takes five years to explore and develop the average generator, the major cost involving drilling and exploration, then construction so that the heated liquid drives a turbine to produce electricity. Because of the layers of Japanese bureaucracy and legal restraints, it actually takes around 10 years from inception to operation.

No Japanese policy-makers have even raised the issue of drilling inside national parks. Instead, there are only hypothetical plans to drill in diagonally from outside park boundaries. According to Japanese geothermal expert Norio Yanagisawa, onsen owners actually have little to fear from geothermal plants, other than their unsightliness, because they drill down 2 kilometers, far below the shallower onsen waters. "I have not heard of any depletion near a geothermal generator." Moreover, many onsen resorts have to allow boiling water to cool before people venture into it. This wasted heat could be used to generate Kalina or binary geothermal plants, which use a liquid with a low boiling point to turn turbines. Onsen are attracting fewer tourists nowadays, and Yanagisawa argues that adjacent geothermal plants would boost the local economy and provide more jobs.

Despite high initial costs, over time the average price of electricity generated by geothermal plants is comparable to nuclear power. Yet the Japanese research budget for geothermal was eliminated in 2003, and only a trickle has been restored. In 2000, there were 40 people in Yanagisawa's group. Today there are five.

Geo-heat Can Be Used Anywhere
For some distance below the earth's surface, the underground temperature remains stable year-round. Another form of geothermal energy, which the Japanese called "geo-heat," takes advantage of this fact in order to cool or heat buildings and water. Pioneered in Hokkaido in the 1980s, geo-heat systems began to gain ground in 2004, when the first domestic Japanese mass-produced compact heat pump unit was released. Most systems have been installed in schools, hospitals, shopping centers, greenhouses, and hotels.

Nonetheless, this form of geothermal energy is in its infancy, and there are many prefectures without any systems at all. At his five-story Tokyo apartment building, I met Masakatsu Sasada, the energetic, upbeat chairman of the Geo-Heat Promotion Association of Japan. A former geothermal expert at AIST in Tsukuba, he retired and focused on geo-heat because it can be used anywhere. In 2008, he retrofitted his apartment building. Sasada bored eight holes, 15 centimeters in diameter, 75 meters down in his parking area, then installed a U-shaped pipe in each hole to carry antifreeze in a closed loop system.

The underground temperature is always 18 degrees Centigrade (nearly 65 degrees Fahrenheit), about the same as Tokyo's average. During the winter, when the antifreeze is circulated out of the ground into colder air, a heat pump on the roof uses the differential to extract heat. In the summer, the antifreeze coming out of the earth is cooler than the ambient air, and the heat pump can use that difference to air condition the apartments. In the spring and fall, when there are days that the outside temperature is 18 degrees and there is no differential, the geo-heat system won't work.

There is no established well-drilling industry in Japan, since the ample rainfall allows people to use ground water. I observed that people who could tunnel through mountains and throw cement up cliffs and along rivers could certainly drill six-inch diameter holes in the ground. In fact, the YBM Company in Kyushu (where YBM once helped dig for Japan's now-depleted coal) has made a high-frequency vibrating drill that can make a deep borehole in a couple of days with minimal noise.

Still to Come....
In my third and final post, I will write about Japan's wind turbines, hydro-power, biomass, energy efficiency efforts, transit, food, recycling, lifestyle changes, new feed-in tariff legislation, and the future of Japan.

Mark Pendergrast is the author of Inside the Outbreaks: The Elite Medical Detectives of the Epidemic Intelligence Service (which was featured in the ScienceBlogs Book Club) and several other books, including, most recently, Japan's Tipping Point. Email and book information is available at his website.