Energy consumption and the associated \(CO_{2}\) footprint of Information and Communication Technology (ICT) has become a major concern. Some estimates suggest that 4–6% of global electricity consumption in 2020 was spent on ICT and, although the ICT industry is very good at using green energy, \(CO_{2}\) emissions from ICT are at par with or has overtaken \(CO_{2}\) emissions from aviation. Pessimistic forecasts suggest that electricity consumption from ICT may rise to 20% in 2030. Clearly software does not emit \(CO_{2}\) , but software is executed on hardware, and hardware consumes energy when executing software. In recent years there has been a huge effort in understanding the relationship between software and energy consumption of the underlying hardware. There is now evidence that the structure of the software, the program constructs used in the software and even the programming languages and compilers used for developing the software influence the energy consumption when the software is executed. There is a huge global effort on raising awareness of sustainable software development and there is a growing body of knowledge of many aspects. However, the literature on how programming language design and analysis can impact energy consumption of the underlying hardware is sparse. In a seminal presentation at SAS’07 Alan gave an overview of the changes going on in hardware and outlined his view on the implications of this on programming language design and analysis research. In this paper we follow in Alan’s footsteps and outline our view on the implications of energy consumption on programming language design and analysis research.