Pipe Rail

Pipe rail is a the term given to a hydronic heating system where steel pipes are run up and down the rows of plants.  The hot water is generated at a central heating unit outside of the greenhouse.  Then it piped through the "pipe rails" inside the greenhouse where it gives off it's energy to the surrounding environment.  In the first picture below the pipe rails are kept clear of the path as the grower operates trolleys with pneumatic wheels.  In the second picture, the pipe rails are in the path.  This tomato grower uses the heating pipes as a railway for their electric driven trolleys.  Not only do the trolleys drive up and down the rows, they telescope up and down enabling the workers to perform operations on the full height of the plant.