【单选题】根据以下材料,回答题 Better Solar Energy Systems: More Heat, More Light Solar photovoltaic thermal energy systems, or PVTs, generate both heat and electricity, but__________ (51) now they haven't been very good...
【单选题】Choose the word or phrase that is closest in meaning to the underlined part. NASA worked in the 1970s and early 1980s to research the possibilities of using Solar Power Satellite (SPS) systems with la...
A.
shed solar energy to the Earth’s surface from the satellite
B.
set the satellite down to the Earth’s surface with power
C.
shut down the power on the Earth’s surface from the satellite
D.
switch off power to the Earth’s surface from the satellite