Sunday, June 22, 2008

HVDC and the Pacific DC Intertie

Also known as Path 65, the Pacific DC Intertie is an HVDC power transmission line running 846 miles from Celilo, OR to Sylmar, CA. It supplies 3,100 MW of hydroelectric generated power to the hordes of people in the Los Angeles area. This is over 48% of LADWP's peak capacity. More information is available at this Swiss contractor site.

This line is visible for many miles from highways 14 and 395. Many of its pylons are unique in that they use one verticle structure that tapers to a point on a concrete pad, and they have only 2 arms to support the power lines. In my photo, you can see the HVDC line running along side a traditional AC line. The lines carry 500 kV DC each. According to Wikipedia, we can thank President John F. Kennedy for approving this public works project in 1961. It was completed in 1970 and has been upgraded several times since.

I took these pics while trying out my new Land Rover's "sand mode" at the Jawbone Canyon OHV area north of Mojave, CA. You can see from the photos that the AC lines generated much stronger magnetic and electric fields. The electric field meter was pegged under the AC lines. The magnetic fields measured 25 and 7 milligauss for the AC and DC lines, respectively.

The first two photos are under the HVDC line. The first shows the electric field and the second shows the magnetic field. The next two photos are taken under the AC lines and they show the electric and magnetic field strengths there.


Scientific American recently proposed that building new HVDC transmission corridors can efficiently bring solar power from the American southwest to the people in other states. This was part of their Jan 2008 cover story: A Solar Grand Plan.

3 comments:

froarty said...

I went looking for HVDC transmission lines after viewing the YOUTUBE "space tether" experiments where unexplained "debris" shaped like UFO's is seen supposedly around the shuttle but suspiciously passes behind the broken tether. Maybe miles of HV tether filmed from a distance provides "temporal" lensing just like a gravity well provides gravitational lensing of objects hidden behind itself. I think shallow angle night photos taken from a distance along the sight line of the electric field might give up some anomalies.

michael said...

Glad you liked the post. Those power pylons had intrigued me for years, so I just had to figure them out.

froarty said...

HVDC transmission lines are unusual. I was surprised to find we had them in the US. They could be usd as a ready made test bed for
a thesis - pass or fail it would be
interesting to experiment with photographing from different distances and angles while treating lengths of the HV field as possible lenses. Just like a magnifying glass you would need to search out the focal point. The HVDC Intertie is somewhere between the numerous UFO Sitings associated with standard AC transmission lines VS the Space Tether voltage - distances. I don't suppose any UFO or time anomalies rumored about the lines?