This paper demonstrates the interactive user interface P rivEx that helps data producers to reduce privacy risks raised by data collection from service providers in the Semantic Web of Things. P rivEx provides several types of support to data producers in their management of the tension between the privacy risks and the utility of the data they accept to publish. P rivEx is grounded on the formal framework presented in [1] for detecting automatically privacy risks raised by utility queries. In the demonstration, we will illustrate the functionalities of P rivEx, on a smart meter scenario inspired by a real-world use case providing time series of electrical consumptions of different customers associated with some metadata on their demographics, home sizes and equipment.