DES MOINES, Iowa (AP) _ Many Iowans can expect higher electric bills soon, thanks to higher summer temperatures and higher rates being charged by MidAmerican Energy.

The Des Moines Register reports ( ) that the Des Moines-based utility is notifying customers their bills will likely climb during the summer months of June, July, August and September.

MidAmerican Energy spokeswoman Ruth Comer says summer rates are higher “because our cost to produce electricity increases … as demand increases.”

In addition, MidAmerican is raising its base rate this month by 3.5 percent, thanks to Iowa regulators who approved three years of rate increases.

Last year’s 3.6 percent annual average increase didn’t become effective until September. Comer says the average annual increase next year will be 3.3 percent.