Forecasting coal power plant retirement ages and lock-in with random forest regression

Averting dangerous climate change requires expediting the retirement of coal-fired power plants (CFPPs). Given multiple barriers hampering this, here we forecast the future retirement ages of the world’s CFPPs. We use supervised machine learning to first learn from the past, determining the factors that influenced historical retirements. We then apply our model to a dataset of 6, 541 operating or under-construction units in 66 countries. Based on results, we also forecast associated carbon emissions and the degree to which countries are locked in to coal power. Contrasting with the historical average of roughly 40 years over 2010–2021, our model forecasts earlier retirement for 63% of current CFPP units. This results in 38% less emissions than if assuming historical retirement trends. However, the lock-in index forecasts considerable difficulties to retire CFPPs early in countries with high dependence on coal power, a large capacity or number of units, and young plant ages

Product flow analysis using trade statistics and consumer survey data: a case study of mobile phones in Australia

This study describes an integrative approach to product flow analysis of (waste) electrical and electronic equipment using trade statistics and consumer survey data. We demonstrate this approach with a case study of mobile phones. Using statistical and empirical data for Australia over 1997–2014, we have shown how different sources of information can be collated and cross-checked to estimate the product in-use stocks and flows, product lifespan and lifespan structure, as well as to detail the product age structure in stock and at the end of life. From our results, the total number of mobile phones in in-use stocks in Australia has been estimated at 46 million at the end of 2014, or about 2 phones per capita. The proportion of phones kept in storage (not being in use) has been constantly rising, reaching 50% in 2012–2014. The average expected lifespan for a mobile phone sold in Australia decreased from about six years in the late 1990s to about five years in the early 2000s, and then stabilised at around four years (±0.5 years). The average time of active use for mobile phones was estimated in the range of 2.0–2.6 years (which includes first use and reuse). The estimated lifespan profile for mobile phones in Australia has been confirmed to be relatively similar to that reported in Japan. While this methodology presented here provided meaningful results, the accuracy and relevance would be improved by better quality of original data. Therefore, in conclusion, we also highlight potential improvements in consumer surveys that would help to enhance the analysis

Understanding the Multi-Faceted Drivers of Increasing Coal Consumption in Indonesia

To meet the Paris Agreement’s climate mitigation objectives, there is an urgent global need to reduce coal combustion. Yet coal usage, particularly in the power sector, is rising in many developing countries. Indonesia is a notable example. While government policy is widely considered as the principle driver of Indonesia’s increasing coal consumption, studies have largely overlooked the influence of socioeconomic forces. To understand these effects, we utilize a decomposition analysis to capture the individual effect of five drivers of coal consumption in Indonesia over 1965 to 2017: (1) the energy mix, (2) energy intensity of GDP, (3) population, (4) urbanization, and (5) urban incomes. Results show the energy mix has exerted the largest effect on coal consumption. In addition, by accounting for other socio-economic influences, we found that other less appreciated factors have contributed to rising coal consumption. In order of contribution these were the urban economic effect, the growing relative share of urban population, and the population increase itself in absolute terms. We thus demonstrate that the drivers of growing coal consumption are multi-faced, complex and intertwined. Our findings show that developing nations such as Indonesia share a need to decouple urban population growth and increasing per capita wealth from fossil fuel (and coal) emissions

Potential for Food Self-Sufficiency Improvements through Indoor and Vertical Farming in the Gulf Cooperation Council: Challenges and Opportunities from the Case of Kuwait

The countries of the Gulf Cooperation Council (GCC) are considered food secure due to their ability to import sufficient food to meet their populations’ demand, despite considerable environmental limitations to conventional agriculture. However, over-reliance on externally produced food leaves these countries vulnerable to food shortages during crises that disrupt international production and shipping. Advanced Controlled Environment Agriculture technology has the potential to improve food self-sufficiency by multiplying vegetable crop yields while optimizing efficiency of agricultural inputs and minimizing land requirements. This paper demonstrates how approximately 15 km2 of indoor farms or less than 0.1 km2 of vertical farms could reduce or eliminate the need to import six important vegetable crops in the State of Kuwait. If properly contextualized and supported by clear legislation and well-managed regulatory bodies, indoor agriculture initiatives may provide a pathway for GCC countries to reduce their dependence on imported foods and increase resilience to food supply disruption during disasters or conflict. This case study contextualizes the need for improved food self-sufficiency in light of vulnerabilities from regional and global threats, illuminates unique challenges faced by GCC countries considering adoption of the proposed technologies, and summarizes opportunities inherent in the current legal and policy framework