Waste-Heat Recovery Credit

Power generated by an exhaust-gas economiser and steam turbine, and the main-engine fuel it displaces. Feeds directly into EEDI innovative-tech credit (Category B) and FuelEU savings.

DesignWHR

Loading calculator…

This calculator requires JavaScript to compute its result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, and limits

P_\text{WHR} \approx P_\text{ME} \cdot \frac{f_\text{exh}}{1 - f_\text{exh}} \cdot \eta_\text{WHR}

Symbol	Meaning	Unit
$P_\text{WHR}$	Electrical power produced by the WHR system	kW
$P_\text{ME}$	Brake power of the main engine at reference load	kW
$f_\text{exh}$	Share of fuel energy leaving through the exhaust (≈ 0.45 for modern two-strokes)
$\eta_\text{WHR}$	Overall heat-to-shaft WHR efficiency - single-pressure 6–8 %, dual-pressure + power turbine 10–12 %
$F_\text{saved}$	Auxiliary fuel displaced by WHR electricity	t
$h$	Running hours at reference load	h
$\text{SFOC}_\text{AE}$	SFOC of the displaced aux engine	g / kWh

Source: IMO MEPC.1/Circ.815 - innovative energy-efficient technologies; MAN Energy Solutions - *Waste Heat Recovery System*

In short

Electric output from an exhaust-gas WHR system and the aux fuel it displaces. Feeds EEDI Category B credit and FuelEU savings.

Learn the theory Decarbonization Technologies for Ships