The environmental impacts of the food system exceed several planetary boundaries, with protein production being a major contributor. Single-Cell Protein (SCP) is a protein-rich microbial biomass that offers a sustainable alternative when derived from renewable energy and sustainable feedstocks. We evaluate the global potential for SCP production utilising electrolytic hydrogen and oxygen, atmospheric carbon dioxide and nitrogen, and hourly-optimised hybrid PV-wind power plants at a 0.45° × 0.45° spatial resolution. We outline a roadmap for industrial-scale production, commencing in 2028, targeting an annual capacity of 30 million tonnes of protein by 2050. Here we show that the cost of renewable electricity-based protein (e-protein) could decline at optimal sites from 5.5–6.1 € kg⁻¹ in 2028 to 4.0–4.5 € kg⁻¹ by 2030, and further to 2.1–2.3 € kg⁻¹ by 2050. Consequently, e-protein production can mostly decouple protein supply from water and arable land constraints, substantially mitigating the environmental impacts of food production.

The aim of this paper was to assess the use and consistency of the time concept in the sustainable consumption context. In this field, time is generally defined as a limited resource, such as money, which is allocated to activities and understood by the activities that it is allocated to. We assessed time as a subject matter in the reviewed articles to verify how it was conceptualized and used in sustainable consumption. During this analysis, we defined six categories: time-use, time of use, time-related rebound effects, time-related value-action gap, time pressure, and time-related well-being. Despite identical definitions, there are some inconsistencies in the essential assumptions regarding time, and we observed that the current recognition of time in sustainable consumption debates is not comprehensive. Clarifying the difference between an objective definition of time and the practical knowledge that people have about time has applications in terms of developing sustainable consumption strategies and policies.

Human wellbeing is essential for sustainable development, requiring the fair fulfilment of basic needs within Earth’s ecological boundaries. This study explores the potential of low-emission quality time as a satisfier of human needs, using Max-Neef’s Human Scale Development model and examining the findings through the lens of sufficiency and sustainability. We address two key questions: (1) What is the potential of quality time, including low-emission and accessible experiences, to satisfy human needs? (2) How do individuals experience quality time in relation to the satisfaction of their needs? Through in-depth interviews, we investigate how individuals’ experiences of quality time meet their needs from two perspectives. First, we focus on needs and their satisfiers, independent of specific individuals. Second, we focus on each participant and reflect on participants’ personal experiences of quality time. Our findings indicate that low-material- and low-energy-intensive forms of quality time, such as spending time with family and friends, engaging in physical activity, and being in nature, can satisfy a wide range of human needs. These experiences are generally accessible and do not require monetary transactions, highlighting their potential contribution to sufficiency-oriented wellbeing. This study contributes conceptually to the transition from consumption-based wellbeing towards models centered on flourishing, self-development, and sustainable lifestyles, offering insights for policy and practice in sustainability science.