A new fee on the electricity bills of National Grid customers, top, goes toward paying the additional cost of buying electricity produced from renewable energy sources, such as wind turbines similar to this one in Hull, Mass.

THE PROVIDENCE JOURNAL / Frieda Squires

Utility provider National Grid has added new fees to the bills of its natural gas and electricity customers that support state-mandated programs for encouraging energy efficiency and increasing the use of renewable energy.

On electric bills, National Grid has added a new Renewable Energy Standard, or “RES,” charge of 0.062¢ per kilowatt-hour, as of Jan. 1.

This is a fee to pay for the additional cost of buying renewable energy in order to meet a minimum requirement established by a 1994 state law.

The RES requires that at least 3 percent of all electricity supplied in the state be generated from renewable resources in 2007. The requirement increases by 0.5 percent each year through 2010, then by 1 percent each year from 2011 through 2014, and then by an additional 1.5 percent each year from 2015 though 2019.

At that point, at least 16 percent of the energy supplied in Rhode Island is to come from renewable energy sources.

National Grid says it has to charge the fee because the company’s long-term contracts with its electricity suppliers have no requirement about where the electricity comes from.

The company says it may have to buy “RECs,” or renewable energy certificates in order to meet its obligations. There is a market for these certificates, which are sold by renewable energy suppliers separately from the electricity they provide. If National Grid doesn’t buy these certificates, its other option is make payments to a newly created state Renewable Energy Development Fund, which will use the money to encourage renewable energy projects within the state.

The RES charge in 2007 will cost a typical customer, who uses 500 kilowatt-hours of electricity a month, an extra 31 cents a month or $3.72 a year.

Toward the end of the year, the actual cost to buy the RECs (or alternative payments) will be reconciled with the charges. Any over-collection is to be given back to ratepayers while any under-collection will be made up through rates going forward.

On the gas side, National Grid began charging, as of Jan. 1, a fee to cover its newly created Gas Energy Efficiency Program. This program, which will be similar to one the company has in place for electricity, will offer incentives and rebates to residences and businesses designed to encourage less usage of natural gas.

The utility company was directed to develop the energy-efficiency plan for its natural-gas customers by the Comprehensive Energy Conservation, Efficiency and Affordability Act of 2006, passed into law last summer by the General Assembly.

The program will provide rebates, ranging from $10 to $800, on the purchase of furnaces, water-heating systems, thermostats and windows, according to the filing submitted to the Public Utilities Commission. The program will also offer free home energy audits.

The new fee is 6.3 cents per decatherm, will cost a typical gas heating customer about 54 cents a month, or $6.48 a year. That’s about a 0.4-percent increase on a typical customer’s bill.

The PUC is still considering how large the program’s budget should be this year, so the agency put the 6.3-cent rate into effect until it makes a final determination.

The fee is about half of what is allowed by the law, which set a maximum fee of 15 cents per decatherm. National Grid has said that as demand for the program grows, the company expects to seek a higher surcharge. The maximum allowed would increase a typical customer’s bill by $1.29 a month or $15.53 a year.

Supporters of the law say that these programs are highly successful in cutting back energy use. For every dollar invested in energy-efficiency programs, there is a return of between $3 and $4, said Matt Auten, an advocate for Environment Rhode Island. Most of that return goes to the customers who participate in the programs.

tbarmann@projo.com