2011 Tōhoku earthquake and tsunami additional power, because TEP's power plants were also damaged in the earthquake. Kansai Electric Power Company (Kepco) cannot share electricity, because its system operates at 60 hertz, whereas TEPCO and TEP operate their systems at 50 hertz; this is due to early industrial and infrastructure development in the 1880s that left Japan without a unified national power grid. Two substations, one in Shizuoka Prefecture and one in Nagano Prefecture, were able to convert between frequencies and transfer electricity from Kansai to Kanto and Tōhoku, but their capacity to do so is limited to 1 GW. With the damage to so
1923 Great Kantō earthquake Tokyo as refuge spots, and public buildings were constructed with stricter standards than private buildings to accommodate refugees. The outbreak of World War II and subsequent destruction severely limited resources. Frank Lloyd Wright received credit for designing the Imperial Hotel, Tokyo, to withstand the quake, although in fact the building was damaged by the shock. The destruction of the US embassy caused Ambassador Cyrus Woods to relocate the embassy to the hotel. Wright's structure withstood the anticipated earthquake stresses, and the hotel remained in use until 1968. The unfinished battlecruiser "Amagi" was in drydock being converted into an aircraft carrier