OFFSHORE WINDCONNECTION & COSTS

Mary Doswell

Alternative Energy Solutions

December 7th, 2010

Virginia Offshore Wind Integration Study

Virginia Beach Transmission System

Study Scope

Landstown Substation

Attachment Facilities – 15 to 25 miles just to shore line. Would be transmission voltage level and possibly need to be multiple DC lines.

Shore Line

Virginia Offshore Border

Once on shore, attachment facilities could extend several more miles to point of interconnection

Distribution voltage lines

Offshore Transmission Station

Study Results 2700 MW Site

Study Results 4500 MW Site

Conclusion

Dominion’s Interest in Renewable Energy

Offshore Wind - Cost Comparison

Cost of N

ew C

ombined C

ycle Gas T

urbineU

S E

IA A

nnual Energy O

utlook 2010

Summary