Energy conservation is key


If all the reactors at Tokyo Electric Power Co.’s Kashiwazaki-Kariwa nuclear power plant in Niigata Prefecture remain offline, and if approval is not given for restarting the Nos. 3 and 4 reactors at Kansai Electric Power Co.’s Oi nuclear power plant in Fukui Prefecture following their just-completed stress tests, Japan will enter the summer without any electricity being supplied from nuclear power plants.

That’s because the No. 3 reactor at Hokkaido Electric Power Co.’s Tomari nuclear power plant in Hokkaido, which is currently Japan’s only operating nuclear power plant, will stop operating in May for regularly scheduled inspection.

As of January, when two of Japan’s 58 nuclear power plants were operating, electricity generated by nuclear plants accounted for just 4.3 percent of the total electricity supply — down from around 30 percent before March 11, 2011, when the earthquake-tsunami struck Tepco’s Fukushima No. 1 nuclear power station.

The only way to cope with the coming situation is to reactivate now-dormant thermal power stations, which use 50,000-kW gas turbine-rotated generators.

In January, Japan’s reliance on thermal power stations shot up to 85 percent of the nation’s total electricity supply. Heavy reliance on thermal power generation has led to a sharp increase in the import of fossil fuels. This is said to be the major factor behind Japan’s trade deficit in fiscal 2011 — the first in 31 years.

Moreover, heavier dependence on thermal power generation is certain to increase carbon dioxide emissions per kW of electricity. If energy consumption for drilling, transportation, the refining of fuel, construction, general operation and maintenance of power stations are excluded, coal-burning power generation emits 864 grams of CO₂ per kW hour, petroleum burning emits 695 grams, and natural gas burning emits 476 grams. The corresponding emissions are zero for hydroelectric power, renewable energy sources and nuclear power.

The total amount of CO₂ emitted from power stations will change depending on the composition of energy sources used for power generation. Statistics from 2009 show that, among principal countries, France had the best record with 90 grams of CO₂ emissions per kW-hour, followed by Canada (167 grams), Russia (317 grams), Italy (386 grams), Japan (415 grams), Germany (430 grams), Britain (450 grams), United States (508 grams), China (743 grams) and India (951 grams). As for the top three, France relies heavily on nuclear power, Canada on hydroelectric power, and Russia on rich natural gas resources. The U.S., China and India rank low because of their heavy dependence on coal.

How long will it take for renewable energy sources to replace nuclear power in power generation?

The answer depends on the workings of the feed-in tariff system to be determined by July. Under the system, power companies will be required to purchase electricity generated from renewable energy sources at certain fixed prices. Since renewable energy sources now generate only 1 percent of electricity in Japan, we should expect that it will take at least 10 years to raise the ratio to 10 percent.

Under these circumstances, reduction of electric power consumption as measured in kW-hours will be necessary to mitigate global climate change. Average monthly electricity consumption by a Japanese household increased from 118.8 kW-hours in fiscal 1970, 185.0 kW-hours in fiscal 1980, 252.4 kW-hours in fiscal 1990 and 291.2 kW-hours in fiscal 1995. After hitting a peak of 303.1 kW-hours in fiscal 2000, it declined to 283.6 kW-hours in fiscal 2009.

After 1995, the figure leveled off then began a gradual downtrend, probably because most households had already purchased air conditioners and other home electric appliances by 1995 and the spread of products using less electricity served to curtail the growth of power consumption.

If policies that provide effective incentives are implemented, and if the public becomes more aware of the importance of saving power, it would be possible to sustain the recent downtrend in electricity consumption.

In Germany, which aims to eliminate all nuclear power stations by 2022, the feed-in tariff system, first introduced in 1990 and later revised twice, proved to be very effective. Electricity generated by renewable energy sources is expected to produce more than 20 percent of the country’s electricity in 2012. In view of the fact that as recently as in 2008, Germany depended on nuclear power for 24 percent of its electricity supply, it seems quite feasible for the country to achieve the target of eliminating all nuclear stations and replacing them with renewable energy sources within the next decade.

On March 8, Tepco announced a plan to raise its electricity charges, saying that its fuel costs in fiscal 2012 will escalate by as much as ¥686.5 billion because none of its nuclear reactors will be operating and the share of thermal power generation will go up from 60 percent to 79 percent of its total power supply. It said that the rising fuel bills will increase the fuel cost per kW-hour of electricity by ¥3.22 but that ¥0.71 of this sum will be offset by management rationalization, such as reducing labor and other costs and disposing of its financial and fixed assets. Thus consumers will be asked to shoulder the net cost increase of ¥2.51 per kW-hour of electricity.

I believe that Tepco’s rate hikes, following the crisis at its Fukushima No. 1 nuclear power plant, are reasonable. In principle, those who benefit from services should pay the costs of the services. After all, businesses and families in the areas served by Tepco have for many years enjoyed an abundant supply of cheap electricity to the disadvantage of communities outside Tepco’s service areas.

Communities that have been forced to bear risks of hosting nuclear power plants have, in return, received government grants-in-aid under the three laws governing the development of locations for new electric power plants.

I believe it’s only logical that cost increases caused by the Fukushima nuclear accident be borne by electricity users. And I don’t think I am alone in thinking that users of Tepco-supplied power should also bear some of the costs of compensating families who were forced to leave communities close to the ill-fated plant as well as costs related to the eventual decommissioning of the Fukushima nuclear power plant.

Takamitsu Sawa is president of Shiga University, Japan.