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A major source of global greenhouse gas emissions is the burning of fossil fuels for the generation of electricity. The portion of electricity generated from fossil fuel varies across regions, and within a region with demand for electricity and the availability of renewable energy sources. Cloud providers operate data centres in locations around the planet. And certain kind of server computation can tolerate migrating between data centres. In this paper we describe the design and implementation of a low carbon scheduling policy for the open-source Kubernetes container orchestrator. We apply this scheduler in a form of demand side management by migrating consumption of electric energy to countries with the lowest carbon intensity of electricity. The primary contributions of this text are (i) the scheduler’s design, which provides a generic model for optimising workload placement in regions with the lowest carbon intensity (ii) an evaluation of its performance in a case study with a major public cloud provider (iii) an implementation of a demand side management solution that consumes electricity where, instead of when, grid carbon intensity is lowest.