Related Party Transactions

12 Months Ended

Dec. 31, 2011

Related Party Transactions [Abstract]

Related Party Transactions

14.  Related Party Transactions

Xcel Energy Services Inc. provides management, administrative and other services for the subsidiaries of Xcel Energy Inc., including SPS.  The services are provided and billed to each subsidiary in accordance with service agreements executed by each subsidiary.  SPS uses the service provided by Xcel Energy Services Inc. whenever possible.  Costs are charged directly to the subsidiary and are allocated if they cannot be directly assigned.

Xcel Energy Inc., NSP-Minnesota, PSCo and SPS have established a utility money pool arrangement with the utility subsidiaries.  See Note 4 for further discussion of this borrowing arrangement.

The table below contains significant affiliate transactions among the companies and related parties for the years ended Dec. 31:

(Thousands of Dollars)	2011		2010		2009
Operating revenues:
Electric	$	7,187	$	6,805	$	5,976
Operating expenses:
Purchased power		10,896		9,428		7,751
Other operating expenses - paid to Xcel Energy Services Inc.		118,370		109,111		96,375
Interest expense		83		90		106
Interest income		1		25		495

Accounts receivable and payable with affiliates at Dec. 31 were:

	2011					2010
	Accounts		Accounts			Accounts			Accounts
(Thousands of Dollars)	Receivable		Payable			Receivable			Payable
NSP-Minnesota	$	1,314		$	-		$	1,610		$	-
NSP-Wisconsin		-			-			-			2
PSCo		-			319			-			2,606
Other subsidiaries of Xcel Energy Inc.		-			11,509			-			21,917
	$	1,314		$	11,828		$	1,610		$	24,525