Energy system transition towards carbon neutrality often involves ambitious substitution of renewable sources for fossil fuels and investment in energy storage to provide regulative flexibility. Yet, radical development of renewable sources may lead to serious asset stranding of existing fossil fuel power, thereby increasing the carbon reduction costs. In this study, new carbon neutralization opportunities are explored in the context of integrated heat and power systems in high latitudes through complementarity of cogeneration retrofit and energy converters. Cogeneration retrofit is an economical option to address the carbon abatement straits as a forerunner and can postpone the construction of flexible energy converters and energy storage for about 10 years. This alleviates potential asset stranding of fossil fuel power, reducing the overall cost by about $ 1.53 billion in Liaoning Province, China. As carbon neutralization progresses, the cogeneration acts as an indispensable backup resource to ease the weather-extreme-induced power shortage.