Idaho Power Co. on June 1 decreased rates by about 4.25 percent for irrigation customers in Idaho, but the Boise-based company slightly increased rates its irrigation customers in Oregon pay.
Tax reforms eased irrigation rates in both states. Oregon customers, however, will pay higher rates because of added costs that include ceasing two coal-fired generating operations.
In Idaho, irrigation rates are dropping by 2.33 percent because of recent tax reforms and by 1.91 percent based on the annual power-cost adjustment, Idaho Power said in a statement.
The Idaho Public Utilities Commission approved the company’s request, commission spokesman Matt Evans said.
Idaho Power each year applies to the commission for a power-cost adjustment reflecting cost increases or savings the company realized in providing power to customers. Company spokesman Jordan Rodriguez said the adjustment takes into account factors such as coal and natural gas prices, and the amount of water available for generating hydroelectric power — the company’s most cost-effective source. If the company has more water available for hydroelectric power generation, it can spend less on other sources.
Federal and state tax reforms that generated cost savings for Idaho Power prompted the company and commission to settle on a method by which the company shares those savings with customers. The method, reflected in the new rate package the commission approved, includes a reduction in base rates and a cost offset, the commission said in a release.
Idaho Power is decreasing rates by 7.04 percent overall in Idaho for residential customers and by 6.63 percent for small, general-service customers. Other decreases are 4.48 percent for large general service customers and 5.52 percent for large power users.
The annual fixed-cost adjustment accounted for over half the reduction for residential customers and just over half for small general-service customers — 3.6 and 3.73 percentage points, respectively.
Evans said irrigation, large power and large general-service users are not subject to the fixed-cost adjustment because the commission hasn’t applied it to them to date. And these users have access to other programs that can help Idaho Power manage its costs, such as an incentive for irrigators to have pumps shut off during periods of peak demand, he said.
Idaho Power said its irrigation customers in Oregon would see a combined 2.49 percent increase in rates.
For its Oregon irrigation customers, a 2.69 percent rate decrease due to tax reform was offset by a 3.51 percent increase associated with early cessation of coal-fired operations at the Boardman, Ore., and North Valmy, Nev., power plants — lower than for other customer classes — and a 1.68 percent increase for the annual power-cost update and power-cost adjustment combined, Idaho Power said.
Other overall rate changes for Oregon customers are a drop of 3.27 percent for residential customers and increases of 2.03 percent for small general service, 2.63 percent for large general service and 3.77 percent for large power customers.
Idaho Power said in a separate June 1 statement that the Public Utility Commission of Oregon approved an agreement between the company, commission staff and the Citizens’ Utility Board regarding recent federal tax reform, which reduces residential rates and lessens effective rate increases for other customer classes.
Idaho Power serves more than 547,000 customers in southern Idaho and eastern Oregon.