ALTUS -- The cost of energy is going up, and -- effective immediately -- so are electric bills in the city of Altus.

By a vote of 6 to 2 Tuesday night the Altus City Council raised residential, small and large commercial and industrial electricity rates per kilowatt hour by 4 percent.

"We can't keep paying more and more and not covering it and expect to maintain the margins we need to operate the city," said City Administrator Mike Nettles as he introduced the emergency ordinance, which took effect immediately upon passage.

Councilwoman Peggy Risinger and Councilman Jerry Don Henry cast the two nay votes.

Nettles explained that the cost of energy rates has increased some 4.7 percent since Altus last revised its rates in 2002, and that during a recent council retreat the 4 percent hike was deemed appropriate.

As city administrator, Nettles also holds a seat on the board of the Oklahoma Municipal Power Association, charged with the purchase of power for distribution to Oklahoma towns and cities. The association, he said, strives to purchase power from the least expensive sources -- coal and hydro power.

The most expensive source is natural gas, Nettles said -- even though "we sit on one of the largest natural gas resources in the United States."

Industrial rates in Altus, Nettles said, are among the lowest in the state, and residential rates are "very competitive."

Residential rates in the winter (November through March), for the first 750 kWH, will now be charged at $0.0745 per kWH, up from $0.0717. Each kWH over 750 in the winter will be charged at $0.0421, up from $0.0405.

In the summer (April through October), residential rates for the first 750 kWH, will now be charged at $0.0735 per kWH, up from $0.0707. Each kWH over 750 in the summer will be charged at $0.0745, up from $0.0717.

The difference in residential rates, based on 1,000 kWH per month, is as follows:

In the winter, including the customer charge of $8.50, the price goes from $72.38 to $74.91 -- a difference of $2.51, or 3.5 percent.

In the summer, including the customer charge of $8.50, the price goes from $79.46 to $82.26 -- a difference of $2.80, or 3.5 percent.

According to Public Works Director Robert Stephenson, average residential kWH usage in the summer is 1,300 to 1,400.