HomeMy WebLinkAboutAUTHORIZING RESOLUTION - COU council resolution 2022-47_wind_energy_projectRenewable Energy Fund Round 15
Grant Application – Standard Form
AEA 23046 Page 15 of 40 10/04/2022
3.2.4 Cost Justification
Indicate the source(s) of the cost estimates used for the project budget, including costs for future
phases not included in this application.
As of submission of this REF15 application and via its REF13-funded feasibility and design project,
COU has received a Budget Quotation of $1.27M (plus $350K delivery to Seattle) from EWT for
one DW58-1000 HH46 turbine, dated 11/11/2022. Following review, COU requested EWT to revise
the quotation to include a second turbine, same model, and to delete the cold climate package.
EWT indicated that a degree of cost savings can be expected with a two-turbine order, though
presently of an unknown amount. At present, COU assumes $3.2M for two turbines delivered to
Seattle.
As of submission of this application and via its REF13 project, STG, Inc. provided COU a
preliminary cost estimate of $6.91M to install one wind turbine at the Pyramid site. This includes
mobilization/demobilization, barge transport of turbines from Seattle to a dock in Captains Bay in
Unalaska and then by truck to the site, civil works (access road and pad), foundation, electrical
connection, and turbine testing and commissioning. STG’s estimate includes $0.22M for civil
engineering that will be accomplished in the design phase, hence $6.69 for installation of one
turbine. Following COU’s subsequent decision to install two turbines to better optimize project fixed
costs and provide redundancy, STG has been requested to revise their cost estimate accordingly.
That estimate is pending but is expected to be approx. $9.24M.
Additional expected engineering costs include site-specific geotechnical investigation and
foundation design ($150K assumed), and electrical connection design ($50K assumed). Note that
HDL’s desktop Geotechnical Suitability Evaluation, Unalaska Wind Turbine Site, dated 6/10/2022
indicated a strong likelihood that EWT’s standard gravity mat foundation will be suitable. If proven
true, custom foundation design may not be necessary.
Briefly then, design and construction of a two-turbine project totals $12.79M, as follows:
1. $0.42M remaining engineering (not completed via REF13 project) (REF15 phase 3)
2. $2.85M turbines (REF15 phase 4)
3. $0.70M turbine shipping to Seattle (REF15 phase 4)
4. $9.24M construction (including turbine transport to Dutch Harbor) (REF15 phase 4)
This cost estimate compares to AEA’s project cost assumption of $6,675/kW for a 2,000 kW
project, or $13.35M, in its 2022.11.01 REF Round 15 Evaluation Model spreadsheet.
At the present time an electrical connection and integration analysis by EPS is preliminary. It notes
that extending the existing 34.5 kV distribution line that powers the WTP easily has sufficient
capacity and can be readily extended to the wind site. EPS states that voltage support at the wind
site, likely with capacitors, may be necessary, but will require further evaluation. Further, EPS has
determined that the powerplant SCADA and controls must be modified to handle turbine ramp
rates, and “the addition of a spinning reserve control point, allocated to the wind generation to
monitor diesel generator spinning reserve and dispatch generators appropriately. We currently
have a control system similar to this in Kotzebue that has more wind penetration than what we are
looking at here.” (Dave Buss, EPS, communication).
Possibly EPS will conclude that battery energy storage is necessary to integrate 2 MW of wind
turbine capacity with the six diesel generators and three ORC units in DPU’s powerplants. Should