Due to the publication of fuel prices from January 2011 to March 2011
(trade statistics prices for crude oil, liquefied natural gas (LNG) and
coal published by Ministry of Finance Japan), a fuel cost adjusted unit
price for June 2011 is fixed as per enclosure. 

Fuel cost adjustment system: 
"Fuel cost adjustment system" is a system designed to automatically adjust
monthly electricity fees based on fluctuations in (actual recorded) fuel
prices for crude oil, LNG and coal. 

 http://www.tepco.co.jp/en/customer/guide/fuelcost-e.html

Appendix: Fuel Cost Adjustment in Electricity Fees for June 2011 
                                                     (PDF 17.6KB)