Case Studies

Solar Power Plant Construction

Situation

This solar field was a joint venture between a public power company and an engineering and construction firm to build a 75 MW solar power plant.  Cost overruns were significant primarily because assembly times for each 40 ft. long 1.5 ton mirror frame were triple what was budgeted.  Safety was a primary concern because current assembly methods were highly subject to cause injuries.  On site safety personnel frequently stopped production when they observed an activity they deemed unsafe.

The assembly and construction site was chaotic.  A construction-based approach of throwing more people at the problem had created an unmanageable mob of activity.  Materials were scattered and unorganized.  There was no scheduling evident.  Frantic reorders were constantly being placed because parts that were supposed to be on site could not be located.

Solution

Materials were moved away from the assembly areas to create space for machinery to assist assembly.  Materials were also organized in a ‘warehouse’ configuration.  Specialized carts were built that were towed down the warehouse rows and parts were loaded in reverse order of assembly.  These kits were then delivered to the assembly area. 

The initial assembly method required 6 build stations and movement of a growing frame through the stations.  A new method was established for building the frame in one station only, eliminating movement of the frame along with the associated time requirements and inherent safety problems.

Tool belts were purchased that allowed assemblers to safely carry the proper tools with them.  Application of tools to specific operations was standardized.

A labeling system was implemented that allowed quick kitting and also assisted in making sure the proper components were attached in assembly.

Impact

Assembly time per frame was reduced to the budgeted amount resulting in savings of 100,000 man hours.  Work stoppages by site safety personnel were virtually eliminated.  Two weeks after implementation, reorders for replacement parts dropped drastically.