Renewable energy procurement targets: 24/7 supply-demand matching and relaxations

Corporate renewable procurement targets based on annual matching, where yearly renewable generation equals consumption, can mask periods when companies draw from fossil fuel sources during peak demand or low renewable availability, limiting decarbonization impact. While 24/7 carbon free matching addresses this issue by requiring renewable supply every hour, its stringent requirements can increase costs, creating an adoption barrier that leaves companies between insufficient annual targets and costly granular matching. We bridge this gap by introducing two relaxations: (i) hourly energy matching, requiring a minimum renewable share each hour, and (ii) clean hours matching, requiring full renewable compliance for a fraction of hours. Our analytical results prove that neither relaxation minimizes cost across all demand patterns, establishing that companies must match target design to their specific operational profiles. Using a two-stage stochastic programming model integrating capacity investment with flexibility through battery storage, we provide guidance for practitioners. For companies with stable demand like manufacturing facilities, hourly energy matching ensures consistent renewable use throughout the day at only a 10% cost premium over annual matching, making them ideal when continuous emissions reduction matters. For companies with volatile demand patterns, clean hours matching at 80% coverage can reduce costs by 5% compared to annual matching while guaranteeing full renewable supply during most hours, suiting businesses where concentrated clean periods suffice. Storage reduces operational risk by 25-30% regardless of matching requirement. These findings provide companies with the first quantitative framework for selecting renewable targets aligning with their operational patterns and decarbonization goals.