The challenge for the future Smart Grids is to improve the energy efficiency and enable groups of stakeholders to offer services to customers. An intelligent agent-based ICT infrastructure supplementing SCADA systems is required to support such perspectives of power grids. This paper focus on describing a novel approach, using Service Level Agreements (SLAs) as a tool, for improving coordination between high-level Smart Grid business requirements and low level infrastructure affordances. Monitoring of SLAs and trustworthy data management requires setting up and monitoring clusters of SLAs coordinating sets of relevant stakeholders. We argue that coordinating services with infrastructures using SLA, as a coordination mechanism is a promising approach towards sustainable Smart Grid solutions. A case study of agent-based comfort monitoring and control in Smart homes illustrates our approach and related tools.