Manufacturing cement has a major impact on climate change, resource depletion, and pollution. Selecting sustainable cement alternatives is vital but entails difficult trade-offs between numerous variables. The objective of this study is to determine the most environmentally beneficial method of cement manufacturing by employing an integrated life cycle assessment multi-criteria decision-making technique. The LCA is employed to quantitatively evaluate the environmental effects of ten different methods of cement production across eighteen distinct categories. Meanwhile, the CRITIC weighted TOPSIS and EDAS MCDM approaches are utilized to rank the various alternatives by determining their proximity to the optimal solution. The LCA results showed that CEM III/A slag cement had lower environmental impacts than Portland cement. With a ranking score of 0.9094 and 1.7228 for EDAS and TOPSIS techniques, respectively, both MCDM identified CM10: ground granulated blast furnace slag (GGBFS) as the most recommended. In addition, midpoint characterization revealed that clinker production was responsible for 55% of the global warming impact. Based on these findings, slag cements are more environmentally friendly than Portland cement. Furthermore, an integrated LCA-MCDM approach offers a thorough sustainability evaluation that incorporates many aspects. Overall, this research shows that blast furnace slag cements, notably CM10, are ideal alternatives for reducing the environmental consequences of cement production in a variety of areas. This integrated methodology provides a systematic framework for making informed decisions in the production of sustainable cement.

Several environmental impacts are associated with cement production, ranging from high greenhouse gas (GHG) levels to high energy consumption (fossil fuel and electricity) to high resource usage. Due to the growing demand for cement in the industry and limited studies in South Africa, it is essential to evaluate the environmental impact of cement production in the South African context. In this study, an analysis of the production model of South African (SA) cement plants was carried out to quantify its impacts and decipher how they consequently affect lives, resources, and the ecosystem. This study carried out a Life Cycle Assessment (LCA) of cement using both the mid-point and end-point approaches of the Life Cycle Impact Assessment (LCIA). This study carried out a cradle-to-gate analysis of 1 kg of cement produced in a typical SA plant. The result showed that for every 1 kg of cement produced, 0.993 CO₂ eq was emitted into the atmosphere; 98.8% was actual CO₂ emission, and its resultant effect was global warming, which causes changes in climatic conditions. Also, 1.6 kg of 1,4-Dichlorobenzene (1,4-DCB) eq was emitted into the air and water, which caused high toxicity in these media, and for every 1 kg of cement produced, 0.139 kg of oil eq was produced, and its effect was seen in fossil resources’ scarcity. The end-point result showed that 55,404 was the potential number of human lives that could be endangered annually; 133 species had the potential to be endangered annually, and the effect of a potential scarcity of resources caused a total marginal price increase of ZAR 6.2 billion due to these damages. In conclusion, this study prescribed mitigation and adaptation strategies to counter these environmental impacts.

The cement industry accounts for nearly 8% of global anthropogenic CO₂ emissions, driven largely by energy-intensive clinker production. Valorising industrial and agricultural waste as Supplementary Cementitious Materials (SCMs) presents a viable mitigation strategy, aligning decarbonisation goals with circular-economy principles. This review employs a two-stage screening process and the Evaluation based on Distance from Average Solution (EDAS) method to assess 27 SCMs across technical, environmental, economic, and regulatory dimensions. The results establish a clear hierarchy: fly ash and metakaolin ranked highest, followed by ground granulated blast furnace slag, silica fume, and calcined clay. Life cycle assessment confirms these top-performing SCMs can reduce the global warming potential of cement production by 50–90% compared to ordinary Portland cement. While established SCMs like fly ash offer a balanced profile in durability, CO₂ reduction, and cost, the framework also identifies regionally abundant materials such as steel slag, bagasse ash, red mud, and Rice Husk Ash (RHA), which possess significant potential but require further processing and standardisation. The findings underscore that material consistency, robust regional supply chains, and performance-based standards are critical for large-scale SCM adoption, providing a replicable framework to guide industry and policy stakeholders in accelerating the transition to low-carbon, waste-valorised cement technologies.

While there is strong demand for cement because of its widespread use in modern society, its production is a source of international concern due to the large amounts of energy required and the greenhouse gas (GHG) emissions produced in the process. These GHGs deplete the ozone layer and speed up global warming. Therefore, it is important to investigate several methods of handling this issue, and material replacement has been proposed as the best option among many others. In this study, we examine the different strategies that have employed material substitution to reduce energy use and GHG emissions during the past decade. In this study, we provided an overview of the cement production processes and outlined the various material replacement choices available to us (including waste or recycled materials and other materials). This study found that partial (1–60%) and total material substitution in cement production processes have been reported to lower energy consumption by 5.5% to 40% and greenhouse gas emissions by 1% to 94%. This highlights the importance of material substitution in cement production for reducing energy consumption and emissions of greenhouse gases.

This work presents a multi-stage stochastic optimization model intended to improve investment decision-making for energy projects by incorporating uncertainty in contexts and changes in market pricing. In contrast to conventional deterministic models, which generally concentrate on a singular stage while neglecting the intricacies associated with policy and market uncertainties, our methodology incorporates Conditional Value at Risk as a pivotal risk metric. Across a span of five years, the model predicts how investments will be distributed among three types of electricity projects: Solar Farm, Wind Farm, and Hydro Plant. The stochastic model strategically allocates an investment of USD 16.5 million to achieve an expansion in the capacity of 925 megawatts and an expected portfolio return of USD 1,822,500. Notably, the model maintains a Conditional Value at Risk of USD 100,000 and an impressive Sharpe Ratio of 18.2250, demonstrating its ability to offer improved risk-adjusted returns. This study illustrates the effectiveness of stage stochastic optimization in enhancing diverse and robust renewable energy portfolios.

Proton-exchange membrane fuel cells (PEMFCs) are highly regarded as a promising technology for renewable energy generation; however, the environmental burden in their life cycle is a subject of concern. This study aimed to assess the environmental impact of producing a 1 kW PEMFC by a well-detailed cradle-to-gate evaluation, using mid-point and end-point impact assessment methods. The environmental impacts are related to the extraction of raw materials, consumption of energy, and transportation processes. Mid-point analysis shows that raw materials extraction and processing have a significant share in some impacts, including freshwater eutrophication, human carcinogenic toxicity, and terrestrial acidification. On the other hand, the energy consumed in fuel cell production plays a significant role in the impact categories of fossil resource depletion and global warming. The highest impact is attributed to the human health end-point analysis (0.000866 DALY), followed by the damage to ecosystems (1.04 × 10⁻⁶ species/yr) and resources (USD2013 6.16844). Normalization results further strengthen the importance of human health impacts and the necessity to solve problems regarding toxicity. The results of this work can provide directions toward enhancing the environmental sustainability of PEMFC technology and present a case for adopting a holistic approach to sustainability by looking across the life cycle of the technology.