The global increase of carbon emissions needs to be reduced to keep incremental global warming below 2 degrees. However, in the last decades, Indonesia’s energy supply and demand have been highly dependent on fossil fuels, contributing to high carbon emissions. Most of the non-renewable energy demand comes from transportation and electrification. While in drilling activity, diesel engines produce carbon emissions for mobilization, drilling operation, and site electrification. Carbon emissions reduction is part of the policy of several giant energy companies to achieve net-zero emissions to support environmental sustainability, echoed by Paris Agreement 2015. This preliminary study aims to comprehensively evaluate the activities that generate carbon emissions in geothermal drilling projects. With the case study, the authors offer a numerical approach of emissions calculation that covers from the planning phase until post-operation calculation, including logistics and equipment used in the drilling project. As a result, the authors provide an integrated analysis regarding efficiency options for geothermal drilling operations. This study also proposes a simple economic analysis to achieve lower carbon emissions. From an operational perspective, emissions reduction could be achieved by making resources movement and transportation more efficient, thus directly reducing fuel consumption and emissions. Furthermore, biodiesel and renewable energy to substitute diesel will lower emissions and energy consumption for regular generators and transportation. Moreover, several operational efficiency options that can help reduce carbon emissions are discussed in this research. Then, the digitalization era also plays an important role in increasing efficiency for lowering carbon footprint. Briefly, this research is considered useful for the industry that seeks to deliver an integrated effort to reduce carbon emissions during a geothermal drilling operation. It will serve as a reference to increase awareness in mitigating emissions in geothermal drilling projects to achieve lower carbon drilling operations.