Arizona Public Service, Tucson Electric Power and other regulated Arizona utilities will be required to obtain 15 percent of their electricity from renewable sources by 2025 under a new rule approved by state regulators.

Arizona utilities now only get about 1 percent of their electricity from nonpolluting, renewable sources such as solar and wind power.

``This is a watershed event,'' said Kris Mayes, a member of the Arizona Corporation Commission, which approved the rule. ``We are taking our energy destiny into our own hands.''

The schedule approved this week by the commission calls for 5 percent to come from clean, renewable sources by 2015, with the amount increasing 1 percent a year until the 15 percent is achieved in 2025.

Another commissioner, Bill Mundell, said it is ``pathetic that New Jersey has more solar energy than Arizona,'' adding that will change under the commission's new rule.

But Commissioner Mike Gleason, the only member of the commission to oppose the new standard, said it will be costly for ratepayers because many of the renewable energy sources are far more expensive than conventional energy, such as coal.

``A few years from now when this goes through the roof, people will ask, 'What were they thinking when they passed it with no controls (on the cost)?' `` Gleason said.

According to the commission staff, each residential electric customer would have to pay a maximum surcharge of $1.05 on their electric bills each month to cover the added cost of the program. Currently, the surcharge for renewable energy is 35 cents a month.

The additional cost is small considering that Arizona Public Service has filed a series of rate requests that would raise the average residential bill by $32 a month to cover the soaring cost of natural gas to generate electricity, Mundell said.

The renewable requirement does not apply to customers of Salt River Project, which is not regulated by the commission and has its own program to increase the use of renewable energy.