A Review of Ducted Wind Turbines for Integration into Urban Building Environments, with a Focus on the Invelox System

Ducted wind turbines (DWTs) have been proposed to improve wind energy capture and conversion where conventional open-rotor turbines are constrained by limited wind resources, turbulence, visual impact, or integration requirements. This review examines the engineering principles, major DWT types, and challenges associated with integrating DWTs into building environments. The review compares nozzle/lens, diffuser-augmented, and INVELOX-type systems with particular attention to aerodynamic augmentation, wind-direction sensitivity, geometric requirements, structural integration, noise and vibration, economic feasibility, environmental effects, and regulatory considerations. This paper synthesises findings reported in the literature and identifies areas where evidence remains insufficient for building-scale deployment. A literature-informed multi-criteria decision analysis MCDA is presented as an exploratory comparison tool; its scores are explicitly treated as literature-based judgements rather than measured performance data. The literature indicates that INVELOX-type systems are of particular research interest because of their omnidirectional intake and separation of the collection and generation functions, but published evidence for realistic urban building applications remains limited. Consequently, INVELOX should be regarded as a candidate technology requiring further experimental, numerical, structural, acoustic, economic, and field validation rather than as an established optimum. The review concludes by linking the identified evidence gaps to a staged research agenda involving urban flow CFD, wind-tunnel validation, structural and vibration assessment, aeroacoustics, lifecycle-economic analysis, and building-specific feasibility assessment.