As more U.S. cities and states make pledges for 100% clean-energy goals, one thing stands in their way—how to transmit the enormous amount of electricity they need to accomplish those lofty goals.

It means enormous delays are being encountered by developers of massive power line systems, some in Kansas and Missouri while others involve operators in New Mexico and Colorado.

Greentech Media explored 7 such huge electrical transmission projects that have stalled for one reason or another.

Click here for story.