Hawaiian Electric Co. customers will see their monthly bills go up if a plan to increase an energy-saving fee to 1.5 percent from 1 percent is approved.

The utility’s residential and business customers have been paying into the "public benefits fund" since 2009 to underwrite the cost of a wide range of incentives, including rebates for the purchases of solar water heaters, energy-efficient appliances and compact fluorescent light bulbs.

The fund, administered by a private contractor, was created to take over energy-efficiency programs previously overseen by Hawaiian Electric Co., the state’s largest electric utility.

A residential customer using 600 kilowatts of electricity per month currently pays $2.86 into the fund, up from $1.19 a month last year. The surcharge will rise again next year if the Public Utilities Commission approves the proposed increase in the funding formula, which is based on a percentage of HECO revenues.

The current fee generates the equivalent of 1 percent of revenue from HECO utilities on Oahu, the Big Island, Maui, Molokai and Lanai. HECO collects the amount from its customers and passes it along to Science Applications International Corp., the company contracted to run HECO’s energy-efficiency efforts. SAIC operates locally as Hawaii Energy.

The state Office of the Consumer Advocate and HECO recommended the amount collected be increased to 1.5 percent of revenue in 2011 and 2012, and 2 percent of revenue thereafter. The PUC is scheduled to rule by December on the proposed hike to 1.5 percent.

In a separate proceeding, the PUC is reviewing whether the planned increases will be sufficient to meet the state’s energy-efficiency goals. That ruling isn’t expected until sometime after July 2011, according to the PUC.

State officials have set a target of reducing energy consumption by 30 percent over the next 20 years through efficiency and conservation programs. That is in addition to a goal of generating 40 percent of the state’s energy with renewable sources over the same period.

Compact fluorescent light bulbs were the largest single contributor to the program’s energy savings in its first year, with more than 1 million bulbs accounting for 50 percent of the energy reductions, according to Energy Hawaii’s annual report. Commercial lighting was second with a 22 percent share, while solar water heaters were third at 8 percent.

Also this week, Hawaii Energy announced the availability of a federally funded incentive program that allows homeowners to save $1,000 in interest when financing the installation of a solar water heating system. The goal of the program is to increase the installation of such systems, which is currently about 4,000 a year statewide. For more information, call Hawaii Energy at 537-5577 or go to their website, hawaiienergy.com.