6 80 60 40 Record High (°F) Average High (°F) Average Low (°F) Record Low (°F) 20 5 4 3 2 1 0 Ja nu Fe ary br ua r M y ar ch Ap ril M ay Ju ne Ju A ly Se ug pt ust em b O er ct N ob ov e e r D mb ec e em r be r 0 Ja nu Fe ary br ua r M y ar ch Ap ril M ay Ju ne Ju Au ly Se g pt ust em b O er ct N ob ov e e r D mb ec e em r be r Temperature (°F) 100 Average Precipitation (in) 120 (a) (b) Figure 2. The monthly climate data for St. Thomas, U.S. Virgin Islands: (a) temperature and (b) precipitation. (Source: weather.com.) 24.9 and 34.5 kV for St. Thomas and St. Croix, respectively. St. Croix is currently in the process of upgrading parts of its system to operate at 69 kV. The distribution systems are typically operated at 13.8 kV. The total technical and nontechnical losses were estimated at 6% on the St. Thomas-St. John system and more than 13% on the St. Croix system. Energy Cost Similar to many island communities, the U.S. Virgin Islands are 100% dependent on imported fuel oil for electricity. Retail electricity rates in 2011 reached as high as US$0.49/kWh and were as high as US$0.52/kWh following the oil price spikes of 2008. The electricity generation and distribution systems in the U.S. Virgin Islands are owned, operated, and maintained by the Virgin Islands Water and Power Authority San Juan Vieques 22 3 Bayamón Carolina 52 Puerto Rico Fajardo Ceiba Caguas 53 San Lorenzo Cidra Humacao Cayey Yabucoa 52 Figure 3. Tourism is the primary economic activity in the U.S. Virgin Islands, which are known for their white-sand beaches. (Photo courtesy of http://www.imagebrowse.com/us-virgin-islandbackgrounds/.) St. Thomas Charlotte Amalie British Virgin Islands St. John Vieques Guayama St. Croix Virgin Islands Figure 4. The conceptual interconnection between the U.S. Virgin Islands, Puerto Rico, and the British Virgin Islands. (The line information is from a public report: http://www.viwapa.vi/AboutUs/Projects/ProjectDetails/11-08-02/USVI-BVI-Puerto_Rico_Interconnection.aspx. Map image courtesy of Google Maps, illustration added.) IEEE Electrific ation Magazine / march 2 0 1 5 59http://www.weather.com http://www.imagebrowse.com/us-virgin-island http://www.viwapa.vi/AboutUs/Projects/ProjectDetails/11-08-02/USVI-BVI-Puerto_Rico_Interconnection.aspx