December 20, 2011


Kanazawa's Challenge -- Prototype for Local Production & Local Consumption of Energy

Keywords: Newsletter 

JFS Newsletter No.111 (November 2011)
"Initiatives and Achievements of Local Governments in Japan" (No. 36)

Kanazawa City in Ishikawa, a northwestern prefecture in Japan, has been speeding up a local government initiative to introduce renewable energy and utilize untapped energy. This article introduces Kanazawa's initiative, conducted independently of national energy policies, to promote local renewable energy sources in their own way by making the best use of local experience and resources.

Kanazawa is located almost at the center of the country's main island on the coast of the Sea of Japan. The city extends 23.3 kilometers from east to west, and 37.3 kilometers from north to south. The southern part of the city is mountainous, being part of the Hakusan mountain range. In the east, there is Mt. Iozen (939 meters), where many local people have since their childhood enjoyed skiing lessons, hiking, etc.

The northern part of the city consists of the Kanazawa Plain, which faces onto the Sea of Japan. With three plateaus -- Teramachi, Kodatsuno, and Mt. Utatsuyama -- and two rivers -- the Saigawa River and the Asano River -- running through them, the city has a variety of geographical features and enjoys the blessings of nature. Meanwhile, it has developed as Ishikawa's prefectural capital with the expansion of transportation networks and the growth of commerce and industry. Having a population of some 460,000 people, Kanazawa is a leading and highly convenient city serving the Hokuriku area.

Municipal hydropower generation & waste power generation bring the electricity self-sufficiency ratio to 5.6 percent

Hydropower generation has played an important role for a long time as one of the major energy sources in Japan. It does not emit carbon dioxide when generating power, and so it is attracting attention anew as a clean energy source. Because of its humid climate with high precipitation particularly in winter, Kanazawa is well known as a rainy city that has a saying "Don't forget your umbrella even though you might forget your lunchbox." For 90 years the city has used its rich water resources for hydropower generation; it is the only municipality generating hydropower as a business in Japan. There are five hydropower stations in all on two local rivers, the Saigawa R. and the Uchikawa R. Because these are multi-purpose dams, they also serve flood control, irrigation, and water supply needs. These downstream uses can limit output of the hydropower stations. Even so, the maximum power generation capacity is about 33,000 kilowatts and the annual capacity is 140,000 MWh, which can supply the electricity demands of about 40,000 households.

Along with hydropower, the city started waste power generation at incineration facilities as a municipal business as early as 1980, and has also actively introduced natural energy sources such as solar power. As a result, the municipal power generation company generates about 172,000 MWh of electricity, which accounted for 5.6 percent of total city power consumption in fiscal 2010, according to the city. This is greater than the national power self-sufficiency ratio of 4 percent.

In Kanazawa, there are two refuse incineration facilities, the East and West Clean Centers. At these centers, waste heat boilers recover heat generated by burning waste and produce high temperature / high pressure steam to supply heat and electricity. Some of the steam is used by heat exchangers to boil water, which supplies heat for air heating and cooling systems in nearby facilities like gymnasiums, as well as for boilers, swimming pools and so on. Also, while electricity created by driving turbines with steam is supplied to these facilities as well as to the incineration facilities themselves, any surplus electricity is sold.

The total output of both centers is about 29,000 MWh of which 14,800 MWh are being sold to supply power to some 4,000 households.

In addition, a new factory at the West Clean Center is scheduled to start operating in April 2012, increasing its generating capacity from the current 1,600 kilowatts to 7,000 kilowatts. This will lead to an additional 0.7 percent increase in generating capacity of the city's overall facilities. The new factory is designed to incorporate rooftop greening and photovoltaic power generating equipment. It will also be used to teach children about energy.

Preserving the landscape by generating power with PV panels

Since 2003, Kanazawa City has been promoting the introduction of renewable energy sources by awarding subsidies for the placement of home-use solar power generating systems. With the start of the New Purchase System for Photovoltaic Electricity in November 2009, more and more solar power generation systems are being introduced in Japan. Worldwide, the price of PV panels has decreased at an annual rate of 7 percent after adjusting for inflation.

In FY 2010, 220 households received subsidies for the placement of solar power systems in Kanazawa. It was a drastic increase, almost double the number in the previous year. In FY 2011, as of the end of August, twice as many PV systems were introduced as in the same period the previous year, showing a surge of citizen interest in solar power generation. In September 2011, a supplementary budget was approved by the city council for subsidizing the placement of 200 more systems.

Another unique point is that increased subsidies are available for the placement of scenery-friendly solar power generating systems. The city started giving additional 100,000-yen (about US$1,299) subsidies per household for scenery-friendly solar power generating systems in designated tradition-preservation areas. (For ordinary equipment, no additional payment is made. For other areas, subsidies amount to 50,000 yen (about US$649) per household.)

The additional payment system for landscape-friendly equipment was adapted from Kyoto City's system. It shows the city's willingness to preserve the traditional cityscape as a cultural asset as well as putting the city at the environmental front lines.

Micro hydro power generation system--making good use of traditional waterways

"Waterways" (traditional canals) are drawing new attention as a renewable energy source. Kanazawa City has many natural springs and its city waterways are a part of citizens' daily lives. It is famous as "the town of waterways," with networks of waterways flowing among the streets and houses.

Currently, there are as many as 55 waterways in the city, totaling about 150 kilometer in length. Citizens use the waterways to wash clothes, play in the water, cool watermelons and other vegetables in summer and as a convenient place to discard snow from the road in winter.

Micro hydro systems with an output of 100 kilowatts or less are small- scale and relatively simply structured. One advantage of waterways is that they are less affected by weather than solar and wind power. Increasing attention is being paid to how these advantages may help make micro hydro a suitable system for the city's renewable energy project.

There are several issues, however, in deploying micro hydro such as, ensuring stable flow volume throughout the year, impacts on the city landscape, concern about noise pollution among residents living near power generation facilities, and negotiations concerning water rights and river management. Therefore, starting in fiscal 2010, the city has been discussing these issues in the Kanazawa City Global Warming Consultation Committee, composed mostly of experts. In fiscal 2011, the city is planning to conduct a field study of leading cases as well as a local land use suitability study.

Expanding introduction of renewable energy resources

On August 1, 2011, the city established the Kanazawa City Study Group on Introduction of Renewable Energy to reexamine current energy measures and policies after the Great East Japan Earthquake and the nuclear crisis at the Fukushima No. 1 nuclear power plant. The study group consists of seven members from the fields of government, industry, and academia as well as two advisors.

Yukiyoshi Yamano, Mayor of Kanazawa, is requesting that members draw up active proposals, saying, "I hope to see discussions on localized energy utilization suitable for the characteristics of the city including water and forest resources to determine appropriate energy policy for the future of our children." The study group is planning to develop and report to the Mayor on a policy under which a renewable energy introduction plan can be formulated by March 2013.

Based on past experience, including hydro and waste power generation, the city hopes to utilize the traditional asset of its waterways with micro hydro. While preserving the landscape, the city is expanding solar power generation. Kanazawa's attempt has just begun. The city is trying every possibility and will continue to do so in the future.

Japan is a narrow country stretching from north to south. On the same day, it can be snowing in the north while a fisherman wearing a T-shirt goes fishing in the south. Each region needs to identify its weather and geographical conditions and introduce energy policy best suited to it. Kanazawa City is actively pursuing the role of prototype for this attempt. The city is expected to formulate concrete measures and policies; we hope to see clear numerical targets included in the 2013 renewable energy introduction plan.

Written by Kazuko Futakuchi