This is a photo of a complete installation of a Dowland-Bach PAC 1100P Wellhead Control Panel on Pad DD-22 of the Cusiana Oil Field in Colombia, South America. The unit uses solar energy to operate the the four main hydraulic valves on the wellhead tree (shown here in red), monitor wellhead and flow sweep conditions (pressure, temperature), and shut in the well in the event of an emergency (over/under pressure, fire, line rupture, etc.) Photo by Bill Konte.