This document provides an earnings presentation for a 2008 year-end report. Key points include: - 2008 EPS was $1.46 compared to $1.35 in 2007. Regulated operations contributed $1.59 to EPS. - Factors contributing to EPS growth included lower O&M expenses and higher electric and gas margins. - The company has strong liquidity with $1.9 billion in available credit and cash. - 2008 accomplishments included raising $2.3 billion, an S&P credit rating upgrade, and ongoing regulatory filings. 2009 EPS guidance is $1.45 to $1.55.

1. Year End 2008
Earnings Release Presentation
January 29, 2009

2. EPS Results
Fourth Quarter Full Year
2008 2007 2008 2007
Regulated Operations $0.38 $0.33 $1.59 $1.55
Holding Company & Other (0.03) (0.03) (0.14) (0.12)
EPS – Ongoing $0.35 $0.30 $1.45 $1.43
PSRI/COLI Settlement 0.01 0.01 0.01 (0.08)
EPS $0.36 $0.31 $1.46 $1.35
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3. EPS Change From Prior Year
Fourth Quarter Full Year
2008 vs. 2007 2008 vs. 2007
2007 GAAP EPS $ 0.31 $ 1.35
PSRI/COLI IRS settlement (0.01) 0.08
2007 Ongoing EPS 0.30 1.43
Lower O&M expense 0.07 0.02
Higher electric margins 0.02 0.03
Higher natural gas margins – 0.06
Higher AFUDC - equity 0.01 0.06
Higher depreciation and amortization – (0.03)
Higher conservation and DSM expenses – (0.02)
Higher financing costs (0.03) (0.05)
Dilution (0.02) (0.03)
Other 0.01 (0.01)
2008 GAAP EPS $0.36 $1.46
2008 PSRI/COLI settlement (0.01) (0.01)
2008 Ongoing EPS $ 0.35 $ 1.45
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4. Electric Margin Change From Prior
Year
Fourth Quarter Full Year
Dollars in millions
2008 vs. 2007 2008 vs. 2007
Retail rate increases (WI, ND, NM, TX) $ 17 $ 48
Conservation and non-fuel riders 10 28
Sales growth (excluding weather impact) 6 30
MERP rider 6 23
Increased margin due to leap year – 9
Estimated impact of weather – (49)
Purchased capacity costs (19) (30)
Retail customer sales mix 1 (8)
Trading margin (7) (10)
Revenue subject to refund (nuclear outages) (2) (18)
Other, including fuel recovery 1 1
Total electric utility margin increase $ 13 $ 24
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5. Gas Margin Change From Prior
Year
Dollars in millions
Fourth Quarter Full Year
2008 vs. 2007 2008 vs. 2007
Base rate increase (CO & WI) $2 $ 24
Estimated weather impact 2 10
Sales growth (excluding weather impact) 1 5
Conservation revenues (1) 3
Increased margin due to leap year – 1
Other (3) 3
Total natural gas margin increase $1 $ 46
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6. O&M Expenses Change From Prior
Year
Fourth Quarter Full Year
Dollars in millions
2008 vs. 2007 2008 vs. 2007
Nuclear outage expenses $8 $ (13)
Higher uncollectible receivable costs 7 7
Lower Employee benefit costs (21) (39)
Higher (lower) plant generation costs (15) 9
Higher (lower) consulting costs (7) 7
Higher (lower) material costs (4) 2
Higher (lower) contract labor (4) 4
Higher (lower) labor costs (1) 22
Other, including nuclear plant costs (13) (10)
Total O&M expense decrease $ (50) $ (11)
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7. Strong Liquidity
Liquidity in $Millions as of January 21, 2009
Credit Total
Lines Available Cash Liquidity
HoldCo $ 772 $ 321 $1 $ 322
NSP-M 482 431 2 433
NSP-M
PSCo 675 670 1 671
SPS 248 236 229 465
NSP-WI* 0 0 58 58
NSP-WI*
Total $2,177 $1,658 $ 291 $1,949
* NSP-WI doesn’t have a separate credit facility, instead it has a borrowing
agreement with NSP-M
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8. 2008 Accomplishments
Raised $2.3 billion to finance growth strategy
S&P upgraded unsecured debt ratings
Active on the regulatory front
Made progress on wind generation ownership
Major construction projects remained on schedule
Increase common dividend 3.3% to $0.95 per share
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9. Regulatory Filings
Pending Rate Cases
Minnesota Electric
Colorado Electric
Texas Electric
New Mexico Electric
SPS Wholesale
Completed Rate Cases
North Dakota Electric
Wisconsin – Limited Reopener
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10. 2009 Earnings Guidance
Dollars per share
EPS Range
Xcel Energy EPS $1.45 – $1.55
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