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on the wind project development process, land owner acceptance, local community acceptance, and regulatory approval/compliance requirements. Resolving these challenges is outside the project scope, but they do add an additional layer of complexity to executing on-site manufacturing that needs careful consideration and further investigation.

6.3.2 65 m baseline blade estimate DNV GL analyses initially focused on manufacturing the Baseline 65 m blade to identify and estimate elements where on-site manufacturing deviates from off-site manufacturing. Utilizing the NREL blade model, key variables were isolated and extrapolated to develop estimates of the cost adders for on-site manufacturing of 75 m, 95 m, and 115 m blades. For the Baseline 65 m off-site blade plant, the following operations and labor parameters are established: •

Two production lines operate with three work shifts per day

Blade mold cycles are completed every 24 hours

540 workers are needed to operate the blade factory on a continuous basis -

85% are considered unskilled labor trained to perform specific tasks ($28/hr fully burdened)

-

15% are considered skilled labor with a 25% premium in wage rate ($35/hr fully burdened)

Translating these parameters to an on-site manufacturing scenario, DNV GL assumed: •

No change in production lines, mold cycling or total labor force

Added 20% cost to skilled labor wage as incentive for traveling with mobile factory

Local/regional labor market around the wind project can supply sufficient number of unskilled workers to be trained

The cost implications of on-site manufacturing are identified in two categories, recurring costs, and nonrecurring costs. Recurring costs correspond to costs generated once serial blade manufacturing begins. These serial manufacturing costs are assumed to not differ between wind project sites at which on-site manufacturing is performed. Non-recurring costs correspond to one-time costs incurred each time the onsite manufacturing plant is positioned at a wind project. These correspond to costs that cannot be avoided when relocating the manufacturing facility and costs that cannot be shared across multiple plant deployments.

6.3.2.1 Recurring cost adders Utilizing the baseline off-site blade manufacturing cost of $10.45/kg as the reference for recurring costs, the NREL blade model establishes the following fractional contributions: •

Labor fraction = 30%

Materials fraction = 35%

Tooling utilization = 7%

Other fractional elements into the blade manufacturing costs exist (cost of capital, utilities, building/facility maintenance, overhead, profit) but are assumed to have secondary effects on blade costs when evaluating on-site versus off-site manufacturing.

DNV GL – Document No.: 10080081-HOU-R-01, Issue: C, Status: FINAL www.dnvgl.com

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