Exhibit 24

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ JOHN V. FARACI

John V. Faraci

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ JEAN-PIERRE GARNIER

Jean-Pierre Garnier

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ JAMIE S. GORELICK

Jamie S. Gorelick

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ EDWARD A. KANGAS

Edward A. Kangas

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ ELLEN J. KULLMAN

Ellen J. Kullman

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ CHARLES R. LEE

Charles R. Lee

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ RICHARD D. MCCORMICK

Richard D. McCormick

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ HAROLD W. MCGRAW III

Harold W. McGraw III

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ RICHARD B. MYERS

Richard B. Myers

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ H. PATRICK SWYGERT

H. Patrick Swygert

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ ANDRÉ VILLENEUVE

André Villeneuve

UNITED TECHNOLOGIES CORPORATION

Power of Attorney

The undersigned, as a member of the Board of Directors, or as an officer of UNITED TECHNOLOGIES CORPORATION, a Delaware corporation (the “Corporation”), or as a member of a committee of said Board, or in all of said capacities, hereby constitutes and appoints CHARLES D. GILL, KATHLEEN M. HOPKO and GREGORY J. HAYES, or any one of them, his or her true and lawful attorneys and agents to do any and all acts and things and execute any and all instruments which the said attorneys and agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934 and any rules and regulations and requirements of the Securities and Exchange Commission in respect thereof in connection with the filing of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 2011, including specifically, but without limiting the generality of the foregoing, the power and authority to sign the name of the undersigned, in the capacities aforesaid or in any other capacity, to such Form 10-K Annual Report filed or to be filed with the Securities and Exchange Commission, and any and all amendments to the said Form 10-K Annual Report, and any and all instruments and documents filed as a part of or in connection with the said Form 10-K Annual Report or any amendments thereto; hereby ratifying and confirming all that the said attorneys and agents, or any one of them, have done, shall do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned has signed this Power of Attorney this 6th day of February, 2012.

/s/ CHRISTINE TODD WHITMAN

Christine Todd Whitman