Alternating current (AC) beat out direct current (DC) because it worked well over short distances. But direct current is significantly easier to control on a smart grid and travels better, says Herman J. Trabish.
Trabish talks with Aftab Khan, Vice President and General Manager of U.S. Grid Systems, about why DC will be a big part of the country's smart grid:
"Power on a DC line is completely controlled. If you say, 'I want to bring power from point A to point B and I want exactly this many megawatts on that line,'" Khan said, "the power goes." Theoretically, he added, AC lines can do the same. But in an AC system, "you don't have the ability to manage the power flow from point A to point B directly."
High-voltage direct current (HVDC) lines are currently in use in China, delivering hydroelectric current from remote resources.
FULL STORY: Will Solar, Wind and New Tech Pave the Way for a DC Renaissance?

Trump Administration Could Effectively End Housing Voucher Program
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Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

Ken Jennings Launches Transit Web Series
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Crime Continues to Drop on Philly, San Francisco Transit Systems
SEPTA and BART both saw significant declines in violent crime in the first quarter of 2025.

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Sacramento Plans ‘Quick-Build’ Road Safety Projects
The city wants to accelerate small-scale safety improvements that use low-cost equipment to make an impact at dangerous intersections.
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