NEW DELHI: This summer the intense heat wave will not be the only worrying factor for Delhiites. Electricity bills are expected to shoot up by 5%-20% from June as the Apellate Tribunal of Electricity APTEL ) has pulled up Delhi Electricity Regulatory Commission (DERC) over failure to pass on power purchase adjustment charges ( PPAC ).APTEL has also ordered DERC to pass on the charges for two quarters (from October 2014 to March 2015) within three weeks. A copy of the order has been sent to DERC chairperson PD Sudhakar. The controversial PPAC order for the first quarter of 2015-16 will be heard in July.Sudhakar said they could not comment as the APTEL order was yet to reach them. Sources said the petition to APTEL was filed by Tata Power Delhi in March and pleadings were completed by April. Later, the BSES discoms supported the petition citing worsening financial problems with the withdrawal of PPAC.The discoms stated that they were getting PPAC for three quarters (July 1, 2014 to March 31, 2015) despite submitting petitions to DERC regularly. The charges of July 1 to September 30, 2014 were the first ones denied to discoms. DERC had on November 13, 2014 allowed the charges to discoms, but a day later this order was withdrawn after citing non-furnishing of complete details of the fuel bills of generators.Following this, two more quarters (October 1 to December 31, 2014 and January 1 to March 31, 2015) passed without PPAC charges. While Tata Power Delhi has sought up to 4% in its petitions, BSES discoms Rajdhani and Yamuna have demanded 17%-20%.Discoms claimed they moved APTEL as DERC was mum on the issue. "DERC, in its reply to the interim application by discoms, cited difficulties such as frequent revision of tariffs and adverse public interest for not releasing PPAC. It added that tariff determination for the current year, which will be completed shortly, can accommodate this PPAC so the application should not be allowed," said discom sources.The power distribution companies, however, cited financial crunch and argued that in 2011 the tribunal had passed clear directions that PPAC was to be provided monthly or maximum on quarterly basis.