Given the water sector’s energy-intensive operations, advancing energy efficiency has become a priority for enhancing economic and environmental performance, mirroring trends from other sectors. Nevertheless, despite sustained pressure and investment to implement energy efficiency and sustainability initiatives, many cost-effective opportunities remain untapped, and policy-relevant evidence on the barriers and drivers that determine uptake remains scarce. This study bridges this gap by providing policy-relevant, comparative evidence on the barriers and drivers shaping energy efficiency uptake across upstream and downstream water and wastewater utilities in Portugal. Using a nationwide questionnaire administered to professionals across multiple departments and organizational levels, it examines perceived barriers, drivers, and strategic priorities for the coming decade. Results show marked asymmetries; as upstream utilities emphasize long-term energy strategies embedded across organizational structures and supported by clear legal and regulatory frameworks. Meanwhile, downstream utilities favor economic enablers, such as dedicated financing mechanisms and tax incentives. However, in both segments, institutional commitment emerges as a critical factor. Findings offer actionable policy recommendations for regulators, policymakers, and utility managers seeking evidence-based, subsector-specific, and adaptable interventions and policy frameworks to accelerate persistent and systemic energy efficiency improvements in urban water services, with applicability in jurisdictions facing similar operational and governance challenges. • Nationwide survey compares upstream and downstream water and wastewater utilities. • Policies should be tailored to upstream and downstream differences. • Ambitious long-term energy strategies drive energy efficiency in upstream utilities. • Downstream utilities favor economic drivers like subsidies and financing mechanisms. • Institutional commitment and reputation drive energy efficiency adoption.
Cardoso et al. (Fri,) studied this question.