Exhibit 12.1

ALLIANT ENERGY CORPORATION

RATIO OF EARNINGS TO FIXED CHARGES

	Three Months
	Ended March 31,				Years Ended Dec. 31,
	2008		2007		2007		2006		2005 (a)		2004		2003
	(dollars in millions)
EARNINGS:
Income from continuing operations	$68	.1	$65	.2	$424	.7	$338	.3	$56	.4	$218	.4	$151	.7
Income tax expense (benefit) (b)	40	.4	38	.8	255	.8	203	.0	(52	.9)	91	.2	75	.6
Income from continuing operations before income taxes	108	.5	104	.0	680	.5	541	.3	3	.5	309	.6	227	.3
Fixed charges as defined	42	.1	44	.0	185	.6	213	.4	226	.7	238	.8	247	.1
Adjustment for undistributed equity earnings	(1	.1)	(3	.1)	(7	.8)	(16	.6)	(41	.7)	(21	.0)	(18	.4)
Less:
Interest capitalized	-		-		-		-		3	.4	5	.4	-
Preferred dividend requirements of subsidiaries (pre-tax basis)(c)	7	.3	7	.3	29	.5	29	.3	5	.5	25	.9	24	.5
Total earnings as defined	$142	.2	$137	.6	$828	.8	$708	.8	$179	.6	$496	.1	$431	.5
FIXED CHARGES:
Interest expense	$29	.7	$29	.6	$116	.7	$145	.7	$175	.8	$176	.9	$205	.1
Interest capitalized	-		-		-		-		3	.4	5	.4	-
Estimated interest component of rent expense	5	.1	7	.1	39	.4	38	.4	42	.0	30	.6	17	.5
Preferred dividend requirements of subsidiaries (pre-tax basis)(c)	7	.3	7	.3	29	.5	29	.3	5	.5	25	.9	24	.5
Total fixed charges as defined	$42	.1	$44	.0	$185	.6	$213	.4	$226	.7	$238	.8	$247	.1
Ratio of Earnings to Fixed Charges (d)	3	.38	3	.13	4	.47	3	.32	0	.79	2	.08	1	.75

(a) For the year ended Dec. 31, 2005, earnings as defined were inadequate to cover fixed charges as defined by $47.1 million.

(b) Includes net interest related to unrecognized tax benefits.

(c) Preferred dividend requirements of subsidiaries (pre-tax basis) are computed by dividing the preferred dividend requirements of subsidiaries by one hundred percent minus the respective year-to-date effective income tax rate.

(d) The ratio calculation in the above table relates to Alliant Energy Corporation's (Alliant Energy's) continuing operations. Refer to Note 14 of Alliant Energy's "Notes to Condensed Consolidated Financial Statements" in Alliant Energy's Form 10-Q for the quarterly period ended March 31, 2008 for information related to Alliant Energy's discontinued operations.