In 2007, Honolulu officials announced a plan to reduce the city's power consumption by 10 percent by 2017.

The city also pledged to make energy efficiency a priority when Mayor Mufi Hannemann signed the U.S. Mayors Climate Protection Agreement in 2005.

But the conservation effort is off to a rough start.

Over the past two years, the city's use of electricity has climbed nearly 15 percent.

"It's going in the wrong direction," said City Council member Charles Djou, who sponsored a bill passed by the council last year that requires the city to annually report its energy consumption.

"We want the overall path of energy use to be going down not up," Djou said.

The city said the increased electricity use is due largely to recent upgrades to its Sand Island Waste Water Treatment Plant, which were mandated by the U.S. Environmental Protection Agency and state Department of Health.

The city used 194.4 million kilowatt hours of electricity at a cost of $38.8 million during the fiscal year 2009, which ended June 30. That's up from the 169.3 million kilowatt hours of electricity purchased for $28.5 million in fiscal 2007.

The Department of Environmental Services, which operates the island's waste water collection and treatment system, spent $17.1 million on electricity in fiscal 2009, which was up from $11.6 million in fiscal 2007.

If electricity use by the Department of Environmental Services was excluded, the city's electricity consumption would have decreased by nearly 5.3 million kilowatt hours since fiscal year 2007, the city said in a statement last week.

"There's good news in that we're demonstrating steady progress in decreasing our energy consumption, despite the sharp spike in electricity rates," Hannemann said in a news release last week.

While the city government's electricity consumption is rising, total electricity consumption in O'ahu, Maui and Hawai'i counties during the first half of this year was down 5 percent, according to Hawaiian Electric Co.

The city government's increase in annual consumption — about 25 million kilowatt hours — is enough electricity to power nearly 3,500 Honolulu homes for a year.

The city has been working to reduce electricity consumption, including spending millions of dollars on energy conservation efforts at Honolulu Hale, Neal Blaisdell Exhibition Hall and other city facilities. This year, the city plans to spend $657,000 installing a photovoltaic system at its Halawa Corporation Yard.

The city spent $2.4 million to retrofit Honolulu Hale. The project, which was completed in 2002, was supposed to save the city at least 1.1 million kilowatt hours of electricity. In 2005 the city spent $71,000 installing energy efficient light fixtures in the Blaisdell Exhibition Hall. The modifications were projected to save the city 56,000 kilowatts of electricity annually.

The city auditor last summer criticized the city for lacking a comprehensive framework to effectively manage electricity costs and consumption. The audit also found that the city's sustainability goals lacked a plan for achievement.

According to the audit, the city could not verify whether investments in energy efficiency projects were delivering the promised results. Overall city electricity consumption has risen 20 percent since 2005.