From four days to one: the arithmetic that decides whether a turbine gets cleaned
No maintenance manager says their turbines do not need cleaning. What they say is that this year is not the year. The two statements look contradictory and they are not.
No maintenance manager says their turbines do not need cleaning. What they say is that this year is not the year. The two statements look contradictory and they are not: the second one is not about the condition of the machine, it is about the budget and the outage calendar.
Where the money actually sits
When a wind turbine cleaning quote lands, attention goes to the price per machine. That is natural, it is the number printed on the page. But in a rope access campaign, the contractor price is rarely the line that decides.
The line that decides is downtime. Four to five days per turbine, multiplied by the number of machines in the campaign, is a volume of production that does not get generated. And unlike the contractor price, that figure appears in no quotation: it appears in next month's production report.
Which is why cleaning competes badly internally. Corrective work gets approved because the machine is already down. Preventive work carrying four days of downtime per unit has to justify itself against budget lines that stop nothing.
The same arithmetic, with one number changed
Change that four or five to a one and the whole conversation moves.
One day per turbine is not a marginal improvement on four days. It is a change of category. It stops being an operation that has to be slotted into the annual outage calendar and starts fitting inside a normal maintenance window. It stops needing a capital case and goes back to being what it was: maintenance.
Adding up the reduction in specialist day rates and in production not generated, the saving against rope access sits around 75-80 % of the total operation, not just of the contractor price.
And the line nobody books
There is a third component that almost never reaches the spreadsheet and that anyone running a wind farm will recognise: work at height.
Bringing rope access onto a site carries a real administrative cost. Contractor coordination, verification of personnel certificates, safety plans, supervision during execution. And it carries a risk cost that is not quantified in euros but does show up in decisions: there are O&M managers who have deliberately cut the volume of work at height on their sites, and that policy weighs when a cleaning campaign comes up for approval.
With ground operated drones, that line simply does not exist. Nobody climbs. There is no work at height plan to review because there is no work at height.
What to ask for in the quote
If you are comparing cleaning proposals, these four questions separate a comparable quote from one that is not:
- How many days is each machine down? Not how many days the whole campaign takes. Per machine.
- Who files the permits and how long do they take? If aviation filing falls to the site, that lead time and that work are yours.
- Is public liability cover for the operation included? A thirty second check that avoids surprises at supplier onboarding.
- What is delivered at the end? Before and after photographic evidence per machine, or nothing. Without evidence there is no way to sign off the work or justify it internally.
At Eolinet the answer to all four is fixed in advance: one working day per turbine; aviation permits filed by us with an activation of around 3 weeks; public liability cover included; and before and after photographic reporting for every machine as part of the service.
Cleaning does not get postponed on technical grounds. It gets postponed because the arithmetic does not work. Change the number of days and the arithmetic changes on its own.