OFFSHORE WIND • WTIV • WEATHER DOWNTIME • MARINE SPREAD • INSTALLATION ECONOMICS
Offshore Wind Installation Vessel Cost & Weather Downtime Tool
Convert turbine count, installation cycle time and weather operability into WTIV vessel-days, standby exposure, support-vessel demand, fuel use, campaign duration and marine installation cost. Advanced mode separates offshore phases, vessel fleets, loadout strategy and class-specific weather productivity.
↑Need phased weather windows, feeder strategy or multiple support vessels? Use Advanced.Simple uses one primary WTIV, one blended support spread and one representative installation cycle.
ScheduleWeather-adjusted campaign days
CostWTIV + support + fuel
Unit economics$/turbine and $/MW
Project & Installation Cycle
Exactly ten inputs. Weather operability is a planning percentage of calendar time that is workable for the entered installation spread.
Units in the installation campaign.
MW per turbine.
Productive WTIV hours per turbine.
% of offshore calendar time expected workable.
Mobilization, transit, loadout, positioning and demobilization.
Contract day rate.
% of normal WTIV day rate during weather standby.
Combined support vessels/services per project calendar day.
MT/day across the modeled campaign.
$/MT or chosen currency/MT.
↑Advanced separates installation phases and marine spread exposure.Use project-specific metocean operability, charter terms, vessel limits and port/loadout assumptions where available.
Project & WTIV Fleet
Installation Phase Register
Each enabled phase carries its own productive hours and weather operability. Units default to turbine count but can be overridden for foundations, substations or special lifts.
| Use | Phase | Units | Hours / unit | Workable hrs/day | Weather operability % | Weather uplift % | Port/logistics days |
|---|
Loadout, Transit & Campaign Logistics
Project-wide days.
Project-wide WTIV days outside phase rows.
Additional calendar days.
WTIV Fuel Profile
MT / WTIV-day.
Applied to modeled fuel price for this campaign.
Only used for feeder/mixed strategy.
Support Vessel Fleet
Deployment share applies to modeled project calendar days; fixed days capture mobilization or non-project-window work.
| Use | Vessel / service | Count | Day rate | Deployment % | Fixed days | Fuel MT/day |
|---|
Fixed Cost, Port Logistics & Budget
0 disables budget variance.
0 disables schedule variance.
Stress Cases
| Use | Case | Operability factor | Day-rate factor | Logistics factor | Fuel factor |
|---|
Project Readiness Checks
Campaign screenENTER PROJECT DATAInstallation duration, weather exposure and marine spread economics.
Total marine installation costN/A
Enter project assumptions to calculate the campaign.
CalendarN/A
Weather delayN/A
Cost / turbineN/A
Cost / MWN/A
Installation Schedule BridgeProductive offshore work → weather standby → logistics / loadout → schedule contingency
Marine Cost BreakdownWTIV charter, support spread, fuel, port/fixed costs and contingency
Phase Weather & ProductivityAdvanced mode shows which offshore phase is consuming the weather window
Support Vessel ResultsAdvanced marine-spread vessel-days, charter and fuel exposure
| Vessel / service | Vessel-days | Charter | Fuel MT | Fuel cost | Total |
|---|
Total Cost Sensitivity5×5 weather-operability × WTIV-day-rate matrix
Stress Case ExposureAdvanced mode recalculates campaign cost and duration under editable downside cases
Planning model only. Weather operability is a user-entered accessibility assumption, not a safe-operating limit. Actual duration and cost depend on metocean windows, turbine/foundation design, water depth, soil and seabed conditions, jack-up capability, crane outreach/hook height, feeder interface, port layout, loadout sequencing, vessel availability, contract structure, marine coordination, permits and project-specific lift/installation procedures. Use project-specific metocean analysis, vessel data and commercial quotations before contracting or investment decisions.