Carbon emission pinch analysis for shipping fuel planning considering multiple period and fuel conversion rates

Abstract

In the context of achieving carbon neutrality, reducing CO2 emissions has become an essential task for many countries and poses challenges for various industries. With global trade, the shipping industry is overgrowing, bringing economic benefits but also significant CO2 emissions. To achieve the goal of carbon neutrality, the fuel mix of ships needs to be planned appropriately. As an extension of the base method of Carbon Emission Pinch Analysis, this study develops a new Carbon Pinch Point analysis method for shipping fuel planning. Optimising the energy mix of ships in different period is used to reduce CO2 emissions from shipping fuels and achieve the set emission reduction targets. Taking the Zhoushan sea area in China as an example, emission reduction targets are set in three period with a five-year period from the national policy level. The first period (2020–2025) achieves a 14.5% reduction relative to 2020; the second period (2025–2030) achieves a 32.2% reduction relative to 2020; and the third period (2030–2035) achieves a 57.2% reduction relative to 2020. Each period is divided into Scenario 1 (without heat loss), and Scenario 2 (with heat loss), and two options are developed for each scenario by constraining different low-carbon fuels. The study shows that it is more economical to use LNG as an alternative fuel in the first period, requiring an additional 457.74 kt of LNG in Scenario 1 and 225.26 kt of LNG in Scenario 2. Using biodiesel as an alternative fuel in the second period is more economical, requiring an additional 343.55 kt of biodiesel in Scenario 1313.04 kt of biodiesel in Scenario 2. The use of biodiesel as an alternative fuel in the third period is more economical, requiring an additional 371.73 kt of biodiesel in Scenario 1 and 466.23 kt of biodiesel in Scenario 2.