Exhibit 24-APOWEROF ATTORNEY      I, KEVIN G. MOUG, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, orany one of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asChief Financial Officer and Treasurer of Otter Tail Corporation, the Annual Report of Otter TailCorporation on Form 10-K for its fiscal year ended December 31, 2005, and any and all amendments tosaid Annual Report, and to deliver on my behalf said Annual Report and any and all amendmentsthereto, as each thereof is so signed, for filing with the Securities and Exchange Commissionpursuant to the Securities Exchange Act of 1934, as amended.Date:February 6, 2006                 /s/ Kevin Moug     Kevin G. Moug  In Presence of:   /s/ Nathan Partain      /s/ Lauris Molbert   
 

 
POWER OF ATTORNEY      I, John MacFarlane, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, orany one of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date:February 6, 2006                 /s/ John MacFarlane John MacFarlane  In Presence of:   /s/ John Erickson      /s/ Lauris Molbert   
 

 
POWER OF ATTORNEY      I, Karen Bohn, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, or anyone of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date:February 6, 2006                 /s/ Karen M. Bohn     Karen Bohn  In Presence of:   /s/ Thomas Brown      /s/ Gary Spies   
 

 
POWER OF ATTORNEY      I, Thomas Brown, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, or anyone of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date:February 6, 2006                 /s/ Thomas Brown     Thomas Brown  In Presence of:   /s/ Karen M. Bohn      /s/ Gary Spies   
 

 
POWER OF ATTORNEY      I, Dennis Emmen, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, or anyone of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date:February 6, 2006                 /s/ Dennis Emmen     Dennis Emmen  In Presence of:   /s/ Edward James McIntyre      /s/ Kenneth L. Nelson   
 

 
POWER OF ATTORNEY      I, Arvid Liebe, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, or anyone of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date: February 6, 2006                 /s/ Arvid Liebe     Arvid Liebe  In Presence of:   /s/ Kenneth L. Nelson      /s/ Robert N. Spolum   
 

 
POWER OF ATTORNEY      I, Kenneth Nelson, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, orany one of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date: February 6, 2006                 /s/ Kenneth L. Nelson     Kenneth Nelson  In Presence of:   /s/ Dennis Emmen      /s/ Arvid R. Lieve   
 

 
POWER OF ATTORNEY      I, Nathan Partain, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, orany one of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date: February 6, 2006                  /s/ Nathan Partain     Nathan Partain  In Presence of:   /s/ Joyce Nelson Schuette      /s/ Kevin Moug   
 

 
POWER OF ATTORNEY      I, Gary Spies, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, or anyone of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date: February 6, 2006                 /s/ Gary Spies     Gary Spies  In Presence of:   /s/ Thomas Brown      /s/ Karen M. Bohn   
 

 
POWER OF ATTORNEY      I, Robert Spolum, do hereby constitute and appoint JOHN D. ERICKSON and GEORGE A. KOECK, orany one of them, my Attorney-in-Fact for the purpose of signing, in my name and on my behalf asDirector of Otter Tail Corporation, the Annual Report of Otter Tail Corporation on Form 10-K forits fiscal year ended December 31, 2005, and any and all amendments to said Annual Report, and todeliver on my behalf said Annual Report and any and all amendments thereto, as each thereof is sosigned, for filing with the Securities and Exchange Commission pursuant to the Securities ExchangeAct of 1934, as amended.Date: February 6, 2006                 /s/ Robert N. Spolum     Robert Spolum  In Presence of:   /s/ George Koeck      /s/ Kenneth L. Nelson