As an introduction to this post, it will give you a short introduction to modular wind turbine construction, planning trends, and why lean construction is applicable here. One thing is that wind turbine construction is categorized as modular construction, with a sequential strategy for assembling the modules [1]. Another thing is that the critical path method (CPM) has been and is still the dominant planning method for the wind industry [2]. The last part of this post will focus on the planning in the wind industry, taking an offset in the more complicated offshore wind construction and showing how lean construction would be applicable. Expressed as a short statement:

“it is not about what is being managed, but about how it is being managed.”

The wind energy industry is a much younger industry than the construction industry but continuously expanding. Figure 1 shows by displaying the global installed wind capacity for both onshore and offshore wind turbine installation.

Figure 1. New installed wind energy capacity in GigaWatt per year

The wind farm development projects fall under the category of modular construction, using an Engineering Procurement Construction projects (EPC) contract structure, dividing the work packages per the main components; a) foundations, b) wind turbines, c) cabling between assets, d) transformer stations, e) grid connecting cabling. Figure 2 illustrates the high-level processes for the wind turbine package. The design phase takes the sales contract and transforms it into production orders for the actual project configuration, aligning the tower interface with the foundation and cabling package. The international production facilities then produce and transport the modules for towers, nacelles, and blades to the designated pre-assembly ports, where the modules are prepared for installation. The modules are collected in batches from the port by the installation vessels (large crane vessels), which then transports the main modules to their final assembly location. The crane vessel assembles the modules onto the prepared foundations, a commissioning team completes the turbines and puts them into operations.

Figure 2. A high-level overview of the modular offshore wind construction projects [3].

Adapting lean construction to modular offshore wind turbine construction
When thinking of lean construction methods such as Last Planner System (LPS), Location-Based Scheduling (LBS), and Takt Planning comes to mind. The headline for the adaptations was; deliver projects that satisfy customer requirements, establish production flow, and eliminate waste.

Managing modular wind projects is not different from construction projects. It is a labor intensive production system, where it differs is the usage of vessels for the installation and commissioning of the turbines. The day rates of 200,000 EUR for an installation vessel and 35,000 EUR for the commissioning vessels make it a genuine interest area for all levels of management. But like construction and production, productivity can not be found through a “fancy yellow robot”[4] alone. It is found through working with the teams, trades, or operators. This became obvious during the implementation of LPS [3] and Takt on teams level [5], which the foreman role provides for his team and looks to his manager for guidance and direction when trying to adapt to a different way of thinking productivity. Similar to how Paul describes the 5 levels of LPS here on the blog, preparing for the tasks and looking ahead became crucial.

Learnings from implementation
Implementing lean construction within the offshore wind setting required adaptation of the methods, but mainly it needs the people involved to get engaged. Communication and examples from the lean construction community eased the transition of the mindsets. The lean construction method and reasons for why were introduced to the project organization. In relation to this, concerns among technicians were raised,

1) “this lean thing is just here to make us work faster,” Response - workflows and work sequencing is not related to working faster. It is to ensure both work safety and security while bringing down lead times.

A manager argued that 2) “we usually do things this way, why should we change what has gotten us this far.” Response – I can’t force you into changing. I am providing you tools that can make your planning easier. In the end, you are the ones that have to use it and can potentially benefit from it.

Our finding is that this is not different from implementing a lean construction full scale at a construction project. People, direction, and behavior are necessary to deliver projects on time, within budget, and safely. The findings from our implementation within the wind turbine industry can be applied to other related areas of construction such as solar farms, nuclear power, oil and gas, rail, and infrastructure. The Last Planner System, Takt Time, Location Based Planning, and other Lean principles prove to be universal and highly effective for our team. We hope that other subfields of construction adopt LC methods and principles to improve the quality of the work onsite as well as the quality of the life for the people performing the work.

References:

(1) O’Connor, J.T., W.J. O’Brien, and O.C. Jin, Standardization Strategy for Modular Industrial Plants. Journal of Construction Engineering and Management, 2015. 141(9): p. 04015026.

(2) Lerche, J., et al., Why Would Location-Based Scheduling Be Applicable for Offshore Wind Turbine Construction?, in Proc. 27th Annual Conference of the International Group for Lean Construction (IGLC). 2019: Dublin, Ireland. p. 1283-1294.

(3) Lerche, J., et al., Application of Last Planner System to Modular Offshore Wind Construction. Journal of Construction Engineering and Management, 2020. 146(11): p. 05020015.

(4) Goldratt, E., Theory of constraints. 1999: Great North River Press.

(5) Lerche, J., et al., Continuous Improvements at Operator Level. Journal of Engineering, Project, and Production Management, 2020.