Answer
It is a common operational anomaly for a vessel to show a spike in fuel consumption immediately after emerging from a dry-docking period. The primary technical reasons include:
Hull Coating Hull Roughness: If the underwater hull blasting (SA 2 or SA 2.5 standard) was uneven, or if the anti-fouling paint was applied incorrectly (causing runs, sags, or "orange peel" textures), the surface roughness increases fluid dynamic drag.
Propeller Surface Profile: Mechanical polishing can leave dynamic micro-scratches if executed poorly. Alternatively, if the propeller was coated with a foul-release layer that cured unevenly, it alters the blade profile, reducing propeller efficiency and forcing the main engine to burn more fuel to maintain shaft speed (RPM).
Engine Tuning & Overhaul Settling: Newly replaced piston rings, liner hone marks, and reconditioned fuel injection valves require a brief "running-in" period. High internal frictional resistance occurs until the components conform completely. Additionally, improper timing adjustments of the fuel pumps post-overhaul will drop thermal efficiency.
Alternator/Auxiliary Load Post-Docking: High auxiliary power consumption is typical immediately after docking due to the heavy operation of deck machinery, ballast pumps (rinsing/testing tanks), air conditioning, and ventilation systems clearing chemical fumes.