Rate Matters

12 Months Ended

Dec. 31, 2016

Regulated Operations [Abstract]

Rate Matters

Rate Matters - MGE Energy and MGE.

a. Rate Proceedings.

On December 15, 2016, the PSCW authorized MGE to decrease 2017 rates for retail electric customers by 0.8% or $3.3million and to increase rates for retail gas customers by 1.9% or $3.1million. The decrease in retail electric rates is attributable to declining fuel and purchased power costs. The increase in retail gas rates covers costs associated with MGE's natural gas system infrastructure improvements. The authorized return on common stock equity for 2017 is 9.8% on 57.2% common equity. The PSCW also approved MGE's request to extend the current accounting treatment for transmission related costs through 2018.

In July 2015, the PSCW approved MGE's request to extend the current accounting treatment for transmission related costs through 2016, conditioned upon MGE not filing a base rate case for 2016. This accounting treatment allows MGE to reflect any differential between transmission costs reflected in rates and actual costs incurred in its next rate case filing.

On December 23, 2014, the PSCW authorized MGE to increase 2015 rates for retail electric customers by 3.8% or $15.4 million and to decrease gas rates by 2.0% or $3.8 million. The increase in retail electric rates cover costs associated with the construction of emission-reduction equipment at Columbia, improvements and reliability of the state's electric transmission system, fuel and purchased power related to coal delivery costs, partially offset by lower cost as a result of market conditions for pension and postretirement benefit costs. The authorized return on common stock equity was 10.2%.

The PSCW also approved changes to customer rates and rate design for gas service that became effective January 1, 2015. Gas rate design consists of a fixed monthly customer charge and a variable charge tied to actual usage, in addition to the separate charge through the PGA for natural gas commodity costs. The change shifted more of the rate recovery to the monthly charge, reflecting the related fixed costs of providing gas services, and reduced the variable usage-based charge. Thus, gas net income is expected to be more evenly distributed during the year and less sensitive to weather.

On July 26, 2013, the PSCW authorized MGE to freeze electric and natural gas rates at 2013 levels for 2014. The order authorized 100% AFUDC on the Columbia scrubber construction project and deferral of increased costs related to ATC and MISO network upgrade fees. As part of the rate freeze plan authorized by the PSCW, effective January 1, 2014, approximately $6.3 million associated with a 2012 fuel rule surplus credit was amortized in 2014. The fuel credit accrued interest at MGE's weighted cost of capital. The authorized return on common stock equity was unchanged at 10.3%.

b. Fuel Rules.

Fuel rules require the PSCW and Wisconsin utilities to defer electric fuel-related costs that fall outside a symmetrical cost tolerance band around the amount approved for a utility in its annual fuel proceedings. Any over/under recovery of the actual costs in a year is determined in the following year and is then reflected in future billings to electric retail customers. The fuel rules bandwidth is currently set at plus or minus 2%. Under fuel rules, MGE would defer costs, less any excess revenues, if its actual electric fuel costs exceeded 102% of the electric fuel costs allowed in its latest rate order. Excess revenues are defined as revenues in the year in question that provide MGE with a greater return on common equity than authorized by the PSCW in MGE's latest rate order. Conversely, MGE is required to defer the benefit of lower costs if actual electric fuel costs were less than 98% of the electric fuel costs allowed in that order.

In August 2015, the PSCW approved a $0.00256/kWh fuel credit that began on September 1, 2015, and continued throughout 2016. The fuel credit established a mechanism to return $10.9million of fuel savings to electric customers as a bill credit. MGE returned $2.6million of electric fuel-related savings to customers through bill credits during the period from September 1, 2015, through December 31, 2015. MGE returned $8.3million of electric fuel-related savings during the year endedDecember 31,2016.

In January 2016, the PSCW lowered MGE's 2016 fuel rules monitored costs by $14.8 million as a result of continued lower projected fuel costs in 2016. Also, in March 2016, MGE filed its 2015 fuel plan reconciliation application showing an overcollection of 2015 fuel rules monitored costs. In July 2016, the PSCW issued a final order stating that MGE shall refund the additional fuel savings incurred during 2015 and 2016 for a total of $15.7million to its retail electric customers over a one-month period. In September 2016, MGE returned $15.5million to customers through bill credits.

As of December 31,2016, MGE has deferred $5.6 million of 2016 fuel savings that were in excess of the fuel savings included within the fuel credits referenced above. These costs will be subject to the PSCW's annual review of 2016 fuel costs, expected to be completed in 2017.