This article discusses the importance of time-series data in renewable energy business models and its role in enabling more efficient, scalable, and customer-centric solutions. It introduces several key concepts, including IIoT-optimized time-series and real-time analytics databases, sensor data-driven performance-based contracts, predictive maintenance, virtual power plants (VPPs), and smart storage systems. The article highlights the critical role of real-time high-frequency time-series data in making renewable energy systems more scalable, efficient, and financially viable. The article also emphasizes the need for developers to carefully consider time-series data infrastructure design when building applications to support renewable energy business models. It discusses various aspects of time-series data management, including data lifecycle policies, indexing strategies, query optimization, and integration patterns. The article concludes by highlighting the benefits of using a powerful time-series database like Timescale, which inherits PostgreSQL's reliability and rich ecosystem, to unlock predictive maintenance, dynamic pricing, VPPs, and more in renewable energy applications.