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- Assessing energy, thermal and visual performance of photochromic glazing: From spectrophotometric characterization to building simulationsPublication . Teixeira, Henriqueta; Moret Rodrigues, António; Aelenei, Daniel; Gomes, Maria da GlóriaABSTRACT: Photochromic (PC) glazing is a promising smart glazing solution for enhancing buildings energy efficiency and indoor comfort through its ability to dynamically adjust its optical properties in response to solar radiation. However, studies assessing the global (energy, thermal and visual) performance of this technology are scarce. This work evaluates the performance of a clear double glazing incorporating a PC film. Spectrophotometric tests were first conducted to determine the thermal and optical properties of the PC film, revealing a dynamic visible transmittance and a low UV and near-infrared transmittance. Subsequently, a previously calibrated dynamic simulation model of an office room was used to assess the impact of the PC film on energy consumption (climatization energy needs and energy use considering an ideal air-conditioning system) and indoor comfort (in accordance with useful daylight illuminance, daylight glare index, predicted mean vote, adaptive thermal comfort model and Portuguese legislation) during working hours (9am-6 pm of weekdays) across the climates of three European cities (Lisbon, Berlin and London). The results show that PC glazing can reduce cooling demand in all studied climates. Total energy use decreased by up to 10% in the warmest of the studied climates, while slight increases were observed in the colder climates. Visual comfort improved significantly, with up to 24% and 74% more working hours with useful illuminance and imperceptible glare levels, respectively. Thermal comfort analysis revealed a negligible change in free-float conditions during working hours, and an improvement of up to 20% when the HVAC system was operating.
- Increase the value of wind power plants through the hybridization with solar photovoltaicPublication . Couto, António; Estanqueiro, AnaABSTRACT: The increasing penetration of variable renewable energy sources, such as wind and solar PV, requires these technologies to actively support power system operation through participation in day-ahead and balancing markets, including the provision of ancillary services. In this context, hybrid power plants, where wind and solar PV share a common point of common coupling and are operated as a single unit, can provide technical and economic advantages compared to standalone plants. This work focuses on the “firm capacity” that can be offered in the Portuguese balancing markets using probabilistic power forecasts, considering the hybridisation of existing wind power plants with solar PV units. Results are compared with the standalone wind power plant and feature-based indicators are also explored to assess whether dynamic selection of forecast quantiles can increase the available capacity for balancing market. Two case studies in Portugal with different levels of wind and solar complementarity are considered. Results show that hybrid power plants significantly increase the amount of capacity available for market participation from 20.5% to 66.2% relative to standalone wind power plants. Thus, hybridisation enhances the ability of existing grid assets to provide ancillary services through participation in balancing markets.
- Development of nanostructured sustainable photocatalysts for industrial wastewater remediation with co-generation of H2Publication . Esteves, M. Alexandra; Brites, Maria João de Sousa; Capelo, Anabela; Pasquini, Luca; Mazzaro, RaffaelloABSTRACT: The SPECTRUM project aims to design, develop, prototype, and test lab-scale solar collectors that effectively utilize the entire solar spectrum to cogenerate heat, electricity and hydrogen using industrial wastewater. This report presents the results of the activities developed in Task 1.2 Development of nanostructured low cost and sustainable photocatalysts of SPECTRUM’s Work Package 1, Optimization of the photocatalytic process of wastewater treatment and hydrogen generation. One of the Specific Objectives (SO1) of the SPECTRUM project is to develop low cost and sustainable nanostructured photocatalysts for synergetic pollutants degradation and H2 generation. With this goal, nanostructured titanium dioxide (TiO₂) photocatalysts were developed using copper as an efficient and economical co-catalyst, suitable for large-scale hydrogen production systems. Two series of copper-decorated TiO2 photocatalysts were synthesized, one based on TiO2 nanoparticles (NP) (Series I) and another based on TiO2 nanotubes (NT) (Series II).
- Optimised photocatalytic H2 production using nanostructured low cost and sustainable photocatalystsPublication . Esteves, M. Alexandra; Brites, Maria João de Sousa; Capelo, Anabela; Pinheiro, Carla I.C.; Lanham, Ana; Ramos, Diana; Pedro, GuilhermeABSTRACT: The SPECTRUM project aims to design, develop, prototype, and test lab-scale solar collectors that effectively utilise the entire solar spectrum to cogenerate heat, electricity and hydrogen. SPECTRUM Work package 1 is dedicated to the optimization of the photocatalytic process of industrial wastewater (IWW) treatment and hydrogen generation and is divided in four tasks. This deliverable D1.3 provides an account of the activities carried out in Task 1.3, “Optimization of Photocatalytic H₂ Production Process at Laboratory Scale,” as well as the results achieved during its duration. The photocatalysts developed in Task 1.2, “Development of nanostructured low cost and sustainable photocatalyst”, were tested for hydrogen production in a slurry type batch reactor using UV radiation as light source. In these preliminary assays, synthetic aqueous solutions containing ethanol or glycerol as sacrificial agent (SA) were used to test the performance of a first series of copper decorated TiO2 nanoparticles (NP) photocatalysts. A comprehensive series of experiments enabled the selection of the most effective photocatalyst, Cu-decorated TiO2 nanoparticles with 6 weight % of copper (Cu/TNP-6). This photocatalyst was then utilized with aqueous solutions of ethanol or glycerol to optimize three key operational parameters — pH, photocatalyst concentration, and sacrificial agent concentration. The same methodology was subsequently applied to evaluate the performance of two additional copper-based photocatalyst sets developed in Task 1.2: copper-decorated TiO₂ nanotubes and copper/biochar-decorated TiO₂ nanoparticles.
- Microalgae-Based Treatment of Winery WastewaterPublication . Lopes da Silva, Teresa; Lopes, Tiago; Reis, AlbertoABSTRACT: Winery wastewater (WWW) is a high-strength effluent characterized by high organic load, nutrient content, and seasonal variability, posing significant environmental challenges. This review critically evaluates microalgae-based systems for WWW treatment, addressing their performance, scalability, and role within circular bioeconomy frameworks. Analysis of recent studies shows that microalgae-based systems can achieve high pollutant removal efficiencies, including up to ~ 90–92% chemical oxygen demand removal, high removal of total organic carbon and nitrogen (typically above 80%), and up to 91–95% ammonium removal. These systems also enable the production of biomass rich in proteins (up to ~ 58.8% dry weight) and valuable compounds such as pigments, supporting multiple valorization pathways. A key finding is that, despite strong technical performance, large-scale implementation remains limited. The main constraints are associated with wastewater variability, presence of inhibitory compounds, and operational challenges in biomass recovery, particularly energy-intensive harvesting and downstream processing. Techno-economic and life cycle analyses indicate that standalone systems are rarely economically viable under current conditions, and that feasibility depends on integration into multiproduct biorefineries and existing infrastructures. Regulatory uncertainty and the need for stakeholder acceptance further constrain deployment. Overall, microalgae-based WWW treatment represents a promising but system-dependent solution, requiring integrated technological, economic, and policy frameworks to achieve scalable implementation.