Exhibit 12b

Tucson Electric Power Company
Computation of Ratio of Earnings to Fixed Charges

	12 Months Ended
	Dec. 31,		Dec. 31,		Dec. 31,			Dec. 31,		Dec. 31,			Dec. 31,
	2010		2009		2008			2007		2006			2005
	- Thousands of Dollars -
Fixed Charges:
Interest on Long-Term Debt	$	42,378	$	36,226	$	47,456		$	50,230	$	51,422		$	56,243
Other Interest (1)		433		1,571		1,367			4,538		6,436			2,597
Interest on Capital Lease Obligations		52,534		53,670		57,252			64,477		72,556			79,064
Estimated Interest Portion of Rental Expense		72		106		130			160		188			216
Total Fixed Charges	$	95,417	$	91,573	$	106,205		$	119,405	$	130,602		$	138,120
Net Income	$	106,978	$	89,248	$	4,363		$	53,456	$	66,745		$	48,267
Add:
Cumulative Effect of Accounting Change — Net of Tax		—		—		—			—		—			626
Net Income from Continuing Operations		106,978		89,248		4,363			53,456		66,745			48,893
Add (Deduct):
Income from Equity Investees		—		—		(1,381	)		—		(320	)		(314	)
Income Taxes		61,057		55,130		10,867			35,542		42,478			33,907
Total Fixed Charges		95,417		91,573		106,205			119,405		130,602			138,120
Total Earnings before Taxes and Fixed Charges	$	263,452	$	235,951	$	120,054		$	208,403	$	239,505		$	220,606
Ratio of Earnings to Fixed Charges		2.761		2.577		1.130			1.745		1.834			1.597

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