In a report published earlier this year, the Intergovernmental Panel on Climate Change (IPCC), a United Nations panel of experts, said renewable energy sources could provide up to 77 percent of the world’s energy needs by 2050. Renewable sources, like the wind energy and solar power, are hugely abundant and mostly untapped.
The clean energy future in which renewables will play the central role in powering the world, which has been believed to be far away, is now approaching much faster than expected.
Between 1990, when global warming became a major international issue, and 2010, the amount of electricity generated globally by using wind power increased by more than hundredfold.
Global wind farm generation capacity now stands at 190 gigawatts, compared with the total installed nuclear power capacity of 370 gigawatts, and is growing by 40 gigawatts every year.
Wind turbines currently provides 2.5 percent of the world’s electricity supplies and generates 5 percent of the power consumed in the European Union countries.
Behind Germany’s recent decision to phase out all of its nuclear power plants is the fact that the share of renewable energy sources in the country’s total power supply has increased sharply in the past 10 years, from 4 percent to 17 percent.
The biggest renewable energy source in Germany is wind energy. Wind power is already a practical energy source.
The world’s installed solar energy capacity is close to 40 gigawatts, less than wind power, but is growing rapidly. Last year, more than 15 gigawatts of new solar power capacity were added globally, exceeding the total capacity of 15 standard nuclear reactors.
In addition to the traditional photovoltaic technology of converting sunlight directly into electricity, there are solar power systems that use mirrors or lenses to concentrate solar thermal energy onto a small area to produce heat to drive an engine connected to a power generator.
Japan boasts cutting-edge photovoltaic power generation technology using solar panels. Japan developed practical photovoltaic technology ahead of the rest of the world through devoted joint efforts by the public and private sectors.
Until several years ago, Japan led the world in terms of both installed solar power capacity and production of solar cell panels. Now, Japan ranks third in solar power capacity, following Germany and Spain.
In terms of overall renewable energy utilization, however, Japan is lagging far behind the rest of the world.
Renewable sources–wind energy, solar energy, biomass (like woody fuel), micro hydro and geothermal energy–currently account for only 1 percent of Japan’s energy supply. The share is 9 percent if large-scale hydroelectric power installations like dams are included.
We must confront the reality of renewable energy use in this country symbolized by the puny 1-percent share. Many experts say renewables couldn’t be a viable substitute for atomic energy.
It is, of course, impossible to immediately replace all nuclear power with renewables. One percent is certainly a very small share, but that doesn’t indicate the limited availability of renewable sources. Instead, the figure underscores the fact that renewables have been receiving little effective policy support so far.
Neither the government nor the electric power industry in Japan has been making serious efforts to accelerate the use of renewable energies, disparaging them as "unreliable" and "power sources that are hard to use because of their propensity to fluctuations in output."
Behind their smug disregard for renewables was the belief that nuclear power was a dependable and cost-efficient source of electricity that could meet the huge demand.
In 2004, the Resources and Energy Agency estimated the costs of producing electricity by using various energy sources. The estimates said nuclear power could generate electricity at the lowest cost of 5.3 yen per kilowatt, compared with 11.9 yen for ordinary hydraulic power generation, 10.7 yen for oil-burning thermal power generation, 6.2 yen for liquefied natural gas (LNG) thermal, and 5.7 yen for coal thermal.
But the agency’s cost estimation for nuclear power generation didn’t factor in such policy-related expenditures as subsidies to the local communities around nuclear power plants–more than 400 billion yen per reactor in the 10 years until the start of operation–not to mention the costs of dealing with a nuclear accident that could run up to several trillion yen.
It is time for Japan to reinvent its energy policy.
The basic energy supply plan the government worked out last year calls for increasing the share of renewable forms of energy in total primary energy supply to 10 percent by 2020 while envisioning the construction of nine new nuclear reactors.
But it is no longer possible to build new reactors. The government has no choice but to change its energy policy in the direction of reducing Japan’s dependence on nuclear power and expanding the use of renewable sources.
The most promising renewable in Japan is wind power. According to a conservative estimate by the Environment Ministry, wind power available in Japan could potentially generate as much electricity as seven to 40 nuclear reactors combined.
But Japan’s installed wind power capacity is still minuscule, partly because wind power resources that can be tapped are concentrated in such regions as Hokkaido, Tohoku and Kyushu. In addition, utilities have been reluctant to accept electricity generated with wind power into the grid.
If Tohoku Electric Power Co., which serves an area blessed with abundant wind power resources, and Tokyo Electric Power Co., which supplies power to a vast market, start integrated operation of their power grids, Tohoku would be a center of wind power generation.
The nation’s wind power capacity would rise rapidly if the grids are enhanced and interconnected for smooth nationwide power transmission.
Japan’s installed photovoltaic power capacity is 3.6 gigawatts. There is solid public support for solar power.
Continuous and effective policy support would significantly accelerate the deployment of solar power. The installation of solar panels doesn’t have to be limited to narrow spaces on roofs.
We could build small-scale solar farms in idle farmland and large solar power plants in wastelands.
Japan is a volcanic country. But the country’s enormous geothermal energy resources–one of the world’s largest–remain mostly untapped.
Japan is also blessed with abundant forest resources, with two-thirds of the national land covered by green mountains. We should make greater use of biomass energy for heating and power generation.
Research in power generation using ocean currents and wave power is also under way in Scotland and other parts of the world. Some experts say after "green energy" the next big thing in power generation is "blue (ocean) energy."
There are a wide variety of renewable energy sources waiting to be tapped. Japan has enough technological prowess to develop these resources.
It is important to build a society where investment in renewable energy is economically viable. The first thing to do is to introduce a system to require utilities to buy all electricity generated by using renewable sources at fixed prices. Such a system would be a powerful driving force of Japan’s move toward a renewable energy future.
Japan’s nuclear power generation also started from zero. The government promoted nuclear power generation by spending time and money on developing long-term nuclear power plans every five years.
The time has come for the government to promote renewable energy with the same enthusiasm and planning ability it once demonstrated for the development of nuclear power.
We also hope power utilities will pay more attention to the great future potential of renewable energy.
The global markets for businesses related to renewable energy are expanding fast. The government should take steps to stoke growth of the domestic markets for renewable energy technology and products to nurture a new export industry.
As typified by micro hydropower and solar power generation, which is familiar to us, renewable energy is fit for small-scale local power generation, practical even for individuals. Grass-roots efforts should be encouraged to promote renewable energy.
Some experts say reducing nuclear power would make it even more difficult to cut carbon dioxide emissions.
Indeed, greater dependence on thermal power generation and rapid growth of renewable energy use could hamper efforts to cut CO2 emissions in the short term.
From the long-term point of view, however, we have no choice but to reduce our consumption of fossil fuels, including consumption for purposes other than electricity production, to harmonize our overall energy use with the health of the planet.
It is necessary to find a way to reduce nuclear power generation that is compatible with the efforts to stem global warming.