Regulatory Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2014

The components of regulatory assets shown on the consolidated balance sheets of NSP-Wisconsin at Dec. 31, 2014 and 2013 are:



(Thousands of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2014				Dec. 31, 2013
Regulatory Assets			Current		Noncurrent		Current		Noncurrent
Environmental remediation costs	1, 11	Various	$	4,376	$	147,793	$	4,376	$	117,684
Pension and retiree medical obligations ^(a)	7	Various	6,837		91,601		8,202		85,220
Recoverable deferred taxes on AFUDC recorded in plant	1	Plant lives	—		16,711		—		12,679
Losses on reacquired debt	4	Term of related debt	801		4,936		801		5,737
State commission adjustments	1	Plant lives	488		11,650		410		9,355
Conservation programs	1	Less than one year	—		—		404		—
Deferred income tax adjustment	1, 6	Typically plant lives	—		1,514		—		1,763
Recoverable purchased natural gas and electric energy costs		Less than one year	6,946		—		673		—
Monticello EPU		Pending rate cases	—		5,237		—		—
Other		Various	588		1,251		—		755
Total regulatory assets			$	20,036	$	280,693	$	14,866	$	233,193


^(a)	Includes the non-qualified pension plan.

The components of regulatory liabilities shown on the consolidated balance sheets of NSP-Wisconsin at Dec. 31, 2014 and 2013 are:



(Thousands of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2014				Dec. 31, 2013
Regulatory Liabilities			Current		Noncurrent		Current		Noncurrent
Plant removal costs	11	Plant lives	$	—	$	123,105	$	—	$	116,293
DOE settlement	11	Less than one year	4,931		—		6,814		—
Investment tax credit deferrals	1, 6	Various	—		9,397		—		9,976
Conservation programs	1	Less than one year	1,010		—		1,187		—
Deferred electric production and natural gas costs	1	Less than one year	—		—		1,542		—
Excess depreciation reserve		Various	10,999		—		—		—
Other		Various	—		172		174		155
Total regulatory liabilities			$	16,940	$	132,674	$	9,717	$	126,424