Exhibit 12(b)

Tucson Electric Power Company

Computation of Ratio of Earnings to Fixed Charges

	Nine Months Ended		Twelve Months Ended		Twelve Months Ended
	September 30,		September 30,		December 31,		December 31,		December 31,		December 31,			December 31,
	2012		2012		2011		2010		2009		2008			2007
	- Thousands of Dollars -
Fixed Charges:
Interest on Long-Term Debt	$	40,562	$	53,927	$	49,858	$	42,378	$	36,226	$	47,456		$	50,230
Other Interest (1)		1,338		1,720		1,127		433		1,571		1,367			4,538
Interest on Capital Lease Obligations		27,419		38,725		44,874		52,534		53,670		57,252			64,477
Estimated Interest Portion of Rental Expense		539		738		795		72		106		130			160
Total Fixed Charges	$	69,858	$	95,110	$	96,654	$	95,417	$	91,573	$	106,205		$	119,405
Net Income	$	65,018	$	66,579	$	85,334	$	108,260	$	90,688	$	7,206		$	55,591
Add (Deduct):
(Income) from Equity Investees		—		—		—		—		—		(1,381	)		—
Income Tax Expense		39,423		39,318		52,000		59,936		54,220		12,729			36,940
Total Fixed Charges		69,858		95,110		96,654		95,417		91,573		106,205			119,405
Total Earnings before Taxes and Fixed Charges	$	174,299	$	201,007	$	233,988	$	263,613	$	236,481	$	124,759		$	211,936
Ratio of Earnings to Fixed Charges		2.495		2.113		2.421		2.763		2.582		1.175			1.775

⁽¹⁾  Excludes recognition of Allowance for Borrowed Funds Used During Construction.