http://cdn.c.photoshelter.com/img-get/I0000EjXhqL7CBPE/s/750/750/06AK-3209-12pan-Alyeska-Pipeline.jpg
Home
The Trans-Alaska Pipeline
How They Work
Calculations & Examples
Review of Design and Effectiveness
Bibliography

How Effective Have The Heat Pipes Been?
In the 40 or so years since completion of TAPS, the heat pipes have been in use nonstop. According to Alyeska Pipeline Service Company, a huge majority of the VSM's have not moved or shifted, despite shifting of ground in areas surrounding them. This alone is a testament to the effectiveness of the heat pipes. Alyeska uses inferred imaging to monitor the operation of each individual heat pipe on a 3 year cycle. Ineffective heat pipes will appear cooler on thermal imaging, as they should be hotter than surrounding air. Due to the fact that these are a charged, pressurized system, leaks will develop over time and require repair and recharging. So although additional energy, like an electric motor, isn't needed to cool the ground with a heat pipe, routine maintenance is required. Heat pipes have proven useful in the arctic to maintain permafrost and protect structures in many place besides the Alyeska Pipeline, and are key in the stability and continued success of TAPS.


http://si.wsj.net/public/resources/images/OB-FA304_ev_fro_D_20091203181425.jpg
Heat Pipes in use to keep ground frozen below building in Fairbanks, Alaska