Photo/Illutration A solar power farm in Miyama, Fukuoka Prefecture, cuts back its output at the request of Kyushu Electric Power Co. (Asahi Shimbun file photo)

A utility that primarily provides electricity to northeastern Japan activated a procedure April 10 called “output power control” to halt its renewable energy feed from households and start-ups to avoid widespread blackouts caused by a wide gap in supply and demand.

Tohoku Electric Power Co. was scheduled to perform the shutout between 8 a.m. and 4 p.m. on April 10 and again on April 11.

Other utilities that became overloaded have also resorted to this step, triggering fears it could dampen the momentum for renewable energy, which has rapidly gained traction across Japan, according to experts.

Numerous start-ups have emerged in recent years following liberalization of the electricity supply market with the result that utilities can become overloaded with feeds generated from renewable energy sources like wind and solar power.

On occasion, the volume of renewable output has proved too much for local regions to consume, particularly in spring and autumn when demand for power is low due to infrequent use of air conditioning.

A huge supply-demand imbalance carries the potential of large-scale power blackouts.

For this reason, utilities asked renewable energy suppliers to curtail their production through the output power control procedure to avert blackouts that have the potential to affect millions of households.

The upshot of this is that power generating companies using renewable sources will not be able to recoup their investment for the periods when their energy is not required.

On April 9, Shikoku Electric Power Co. halted accepting electricity created by generators using renewables from 8 a.m. to 4 p.m.

The company said it was unable to head off the step despite cutting back production at its thermal power plants and distributing electricity to regions beyond its jurisdiction.

Kyushu Electric Power Co., a frontrunner in the spread of solar power, has frequently resorted to power control since fiscal 2018.

In fiscal 2020, the utility cut its total output from solar and wind power by 3 percent through power control.

The government, which increasingly has championed renewables as cheap and alternative power sources, is set to raise the share of renewables in the nation’s overall production to 36-38 percent from the current 20 percent or so.

But that could pose all sorts of new challenges for the government and utilities.

Large fluctuations in output by solar and wind power due to weather conditions and climate make it difficult to maintain an equitable supply-demand balance.

The government plans to spend up to 4.8 trillion yen ($38.7 billion) on a long-term project to reinforce power cables distributing electricity to the Tokyo metropolitan area and the Kansai region from local regions, including Hokkaido, Kyushu and Shikoku, so as not to waste renewables generated locally.

Another problem is that the use of industrial size storage batteries is not economically viable yet due to prohibitive costs to develop the technology.

Also, little progress has been achieved in the introduction of rate plans that offer lower electricity rates during the daytime when power supply from solar energy is abundant.

(This article was written by Junichiro Nagasaki and Daisuke Matsuoka.)



Related News