Machteld van Den Broek

A managed transition for the global coal fleet requires robust decarbonization strategies for existing assets. This study develops a plant-level techno-economic framework to evaluate multiple options, including co-firing, carbon capture, and repowering, and applies it to Indonesia's fleet of 115 coal-fired power plants. Under current market conditions with regulated electricity tariffs, most decarbonization strategies are not cost-effective compared to continued coal operation. The analysis reveals that no single solution is universally optimal and the viability is plant-specific. Direct biomass co-firing is the most applicable option, profitable for 22% of the fleet capacity (4.1 GW), while capital-intensive repowering is only viable for small, inefficient units. Conversely, deep-decarbonization technologies like CCS remain unviable without a carbon price above 50 USD/tCO2. The findings demonstrate that a cost-effective transition requires a differentiated and plant-specific portfolio, which is critical for coal-dependent economies worldwide.

A managed transition for the global coal fleet requires robust decarbonization strategies for existing assets. This study develops a plant-level techno-economic framework to evaluate multiple options, including co-firing, carbon capture, and repowering, and applies it to Indonesia's fleet of 115 coal-fired power plants. Under current market conditions with regulated electricity tariffs, most decarbonization strategies are not cost-effective compared to continued coal operation. The analysis reveals that no single solution is universally optimal and the viability is plant-specific. Direct biomass co-firing is the most applicable option, profitable for 22% of the fleet capacity (4.1 GW), while capital-intensive repowering is only viable for small, inefficient units. Conversely, deep-decarbonization technologies like CCS remain unviable without a carbon price above 50 USD/tCO2. The findings demonstrate that a cost-effective transition requires a differentiated and plant-specific portfolio, which is critical for coal-dependent economies worldwide.

We propose an index to quantify and analyse the impact of climatological variability on the energy system at different timescales. We define the Climatological Renewable Energy Deviation Index (CREDI) as the cumulative anomaly of a renewable resource with respect to its climate over a specific time period of interest. For this we introduce the smooth, yet physical, hourly rolling window climatology that captures the expected hourly to yearly behaviour of renewable resources. We analyse the presented index at decadal, annual and (sub-)seasonal timescales for a sample region and discuss scientific and practical implications. CREDI is meant as an analytical tool for researchers and stakeholders to help them quantify, understand, and explain, the impact of energy-meteorological variability on future energy system. Improved understanding translates to better assessments of how renewable resources, and the associated risks for energy security, may fare in current and future climatological settings. The practical use of the index is in resource planning. For example transmission system operators may be able to adjust short-term planning to reduce adequacy issues before they occur or combine the index with storyline event selection for improved assessments of climate change related risks.

We propose an index to quantify and analyse the impact of climatological variability on the energy system at different timescales. We define the climatological renewable energy deviation index (credi) as the cumulative anomaly of a renewable resource with respect to its climate over a specific time period of interest. For this we introduce the smooth, yet physical, hourly rolling window climatology that captures the expected hourly to yearly behaviour of renewable resources. We analyse the presented index at decadal, annual and (sub-)seasonal timescales for a sample region and discuss scientific and practical implications. credi is meant as an analytical tool for researchers and stakeholders to help them quantify, understand, and explain, the impact of energy-meteorological variability on future energy system. Improved understanding translates to better assessments of how renewable resources, and the associated risks for energy security, may fare in current and future climatological settings. The practical use of the index is in resource planning. For example transmission system operators may be able to adjust short-term planning to reduce adequacy issues before they occur or combine the index with storyline event selection for improved assessments of climate change related risks.