Spain is still feeling the painful effects of the costs of overbuilt solar PV, and now Japan is finding itself in the same position. This article does a lousy job of explaining that the grid must be in exact supply and demand balance or the grid can fail. It was designed for one-way centralized power output, which grid operators can “see”. Distributed generation is invisible and going the wrong way, potentially overloading lines and other equipment, which can damage it and bring the grid down. See my posts in Energy / Electric Grid / Grid Instability Distributed Generation, and Renewable Integration for more background on these issues.
Soble, J. March 3, 2015. Japan’s Growth in Solar Power Falters as Utilities Balk. New York Times.
Solar use in Japan has exploded over the last 2 years as part of an ambitious national effort to promote renewable energy. But the technology’s future role is now in doubt.
Utilities say their infrastructure cannot handle the swelling army of solar entrepreneurs intent on selling their power.
Like other countries that have promoted the technology with generous state support, Japan is also struggling with the financial and technical consequences of its rapid solar growth. Solar power here is costly for consumers because of high state-mandated prices, and handling the fluctuating output of thousands of mostly small solar producers is tricky for utilities. Necessary improvements in the infrastructure have not kept pace, experts say.
Utilities need to install more hardware — transmission cables, substations and the like — and develop new kinds of expertise to avoid disruptions. To make renewables work in reality, they have to be properly connected to the power system.
Installed solar capacity roughly doubled since 2012, when a law took effect requiring utilities to buy renewable energy from outside producers at rates far above market prices. By last summer it stood at 3.4 gigawatts, about equal to the output of three modern nuclear reactors but only when the sun was shining at full strength.
An additional 8.4 gigawatts’ worth of projects are planned, imore power than the region consumes on some low-demand days — and far too much for Kyushu Electric’s grid to handle without the risk of failures, the utility argues. New transmission cables are being laid but progress is slowed by the expensive task of securing land rights.
Solar projects have already changed the landscape and economy in Kyushu. They have taken over reservoirs, bankrupt golf courses and idle industrial parks, as well as the more familiar locations of residential rooftops. The largest ones, like the Nanatsushima Mega-Solar Power Plant in Kagoshima, which opened in 2013, cover areas bigger than 100 football fields.
For all the frantic building, however, Japan still produces less solar power than many other countries. Nationwide, just 2.2 percent of its electricity came from any renewable source in 2014 (excluding hydropower from dams).
Catching up [to other nations] would be expensive, even if all the necessary infrastructure existed. Japan’s financial incentives for solar power and other renewables are the highest in the world — about twice the level of Germany, depending on the type of installation.
According to the government, if every solar plant now on the drawing board were actually to be built, it would cost users $23 billion, four times the premium they’re paying now.