Falling cost is one factor driving investment. "Another reason for the boom: Texas recently wrapped up construction of $6.9 billion worth of new transmission lines, many connecting West Texas to the state’s large cities. These massive power lines enabled Texas to become, by far, the largest U.S. wind producer. Solar developers plan to move electricity on the same lines, taking advantage of a lull in wind generation during the heat of the day when solar output is at its highest.
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