Idaho Public Utilities Commission

Case No. PAC-E-11-06, Order No. 32235

May 3, 2011

Contact: Gene Fadness (208) 334-0339, 890-2712



Parties settle on changes to irrigation load control program


The Idaho Public Utilities Commission has accepted a settlement proposed by Rocky Mountain Power, eastern Idaho irrigators and commission staff that will result in less drastic changes to the company’s irrigation load control program than those originally proposed by the company.


Rocky Mountain Power’s Dispatchable Irrigation Load Control program, in place since 2007, allows the utility, during periods of peak demand, to turn off the pumps of irrigators who volunteer to participate. In exchange, irrigators received a credit of $30 per kilowatt. Pumps can be turned off for periods of time during June through August from 11 a.m. to 7 p.m. as long as the utility provides prior-day notification and as long as total curtailment for any participant does not exceed 52 hours.  


On Jan. 20, Rocky Power filed an application to change the program because of voltage problems created by rapidly expanding participation in the program. When the program began in 2007, participating load totaled 65 megawatts, but that increased to 278 MW in 2010. The company claimed that much curtailment was creating voltage control problems with circuits at four substations experiencing unacceptable increases. To respond, Rocky Mountain wanted to reject prospective program participants and reduce the credit irrigators receive from $30 per kW to $25.30.  The company also proposed to modify the penalty irrigators receive for opting out of scheduled curtailments.


Irrigation customers as well as commission staff objected to some of the proposed changes. A negotiated settlement by commission staff, the Idaho Irrigation Pumpers Association and the company will allow the utility to limit program participation to 232 MW for the next two years, or an 18 percent reduction. Further, the $30 per kW credit to each irrigator will be reduced by $1.45 for this season only to account for 11 MW of unobtainable curtailment due to the voltage issues at four substations. In the meantime, the company agreed to invest a minimum of $1.3 million in capital improvements to install equipment needed to address the issues at the four substations before the start of the 2012 irrigation season.


During the two-year period of this settlement, new participants or additional load reduction from existing participants will not be accepted. Volunteer irrigators can decline to participate in some of the curtailments, but the credit they are paid by the company is reduced for each curtailment incident for which the irrigator decides to opt out.


The Idaho Conservation League also participated in the settlement discussions. It did not sign the settlement but does not oppose it.


To read the commission’s final order or other documents related to the case, go to Click on the electric icon, then on “Open Electric Cases,” and scroll down to Case No. PAC-E-11-06.