Evidence of the scale of Japan’s solar boom under the feed in tariff (FIT), which was brought into effect in July 2012, is becoming clear in figures released today by the administrative authority responsible for the photovoltaic installation scheme, METI. The data has been published in Japanese and was covered today by Bloomberg.

While details as to when the 18,681 GW of approved installations needs to be completed and grid connected is not exactly clear, what is clear is that solar in the country is booming. Bloomberg New Energy Finance predicts that between 6.9 GW and 9.4 GW of capacity will be added to the grid in the country in the calendar year 2013.

Looking towards monthly applications for approvals under the FIT scheme, the effect of the reduction in the FIT rate, scheduled for installations approved after March 2013, is evident. Applications for non-residential photovoltaic installations totaled 7.669 GW in March, compared to 5.263 GW in February and 1.892 GW in January.

Applications approved from April 1 receive 37.8 yen/kWh (USD$0.39/kWh).

Indicating that some projects may have been approved however construction and installation delayed, METI issued a statement saying that projects will be investigated. Projects require both METI and local utility approval.

One delay of possible delays that could halt installations are grid challenges facing the island of Hokkaido. Almost one quarter of photovoltaic installations have been proposed on Japan's second largest and most northern island, yet it accounts for less than 3% of the country's electricity demand. Therefore vast grid improvements would be required and some remain skeptical that it will happen, leaving the photovoltaic applications stranded.