Taking in account the conclusions of our previous case-study in the civil engineering course at UTAD (University of Trás-os-Montes e Alto Douro, Vila Real, Portugal) this work presents the results of a case study in an energy engineering undergraduate course. Based on the quantitative and qualitative analysis of collected data, it examines students' attitudes towards web-based peer assessment, distinguishing their role as reviewers or as feedback receivers. It identifies which factors are related to students' use and appreciation of feedback. Moreover, an analysis of the type of feedback is presented in an attempt to evaluate students' written communication skills. The results of this study allow deepening the reflexion on how to improve the design and implementation of future web-based peer assessment tasks.