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Glass Fiber Reinforced Polymer (GFRP) is commonly used in outdoor applications that expose it to environmental conditions capable of degrading its properties, notably ultraviolet (UV) radiation. In this study, we subjected GFRP to UV radiation for a duration of up to 180 days in an accelerated aging chamber. The composites underwent mechanical testing through tensile and flexural evaluations, while chemical and physical changes in the composite were assessed using Fourier-Transform Infrared Spectroscopy, Thermogravimetric analysis, and optical microscopy. Tensile tests revealed a noticeable reduction in GFRP strength after just one month of UV exposure, with a decrease of 18.7% observed at 90 days of exposure. In contrast, the behavior of the composite under flexural testing showed an initial improvement in strength after 30 days of UV exposure, with a significant increase of 54.1%. With longer exposure times, flexural strength gradually decreased but remained 18.9% higher than the strength of the unaged composite after 180 days of UV exposure. Other characterizations indicated material degradation, marked by phenomena such as photo-oxidation, composite yellowing, and the appearance of microcracks on the surface. These factors collectively contribute to the reduction in composite strength. Despite the visible degradation, the aged composite may exhibit improvements attributed to post-curing. However, over more extended periods, it may experience a decline in mechanical properties. Consequently, longer degradation times may unveil a behavior pattern distinct from what is observed during shorter periods, contingent upon the specific mechanical load under consideration. [ABSTRACT FROM AUTHOR]

This paper addresses the urgent need to meet increasing energy demand while avoiding greenhouse gas emissions by improving energy efficiency. One significant challenge is the energy losses that occur during gas pressure reduction at city gates in natural gas distribution systems. To tackle this issue, this study proposes installing pressure reduction turbines (PRTs) parallel to existing reduction valves, which can generate electricity and enhance system efficiency. This research mainly focuses on Brazil’s natural gas supply, where the potential for installing PRTs is evaluated. The methodology analyzes the country’s distribution network and estimates the electricity generation capacity achievable from PRTs. The results indicate a potential power generation of 66 MW, capable of avoiding the emission of 235,800 tons of CO2 annually and generating 333 GWh/year of electricity, all at a LCOE of $27/MW. These contribute to the environment using the energy efficiency achieved through the installation of PRTs, consequently, Brazil can help to a cleaner and more sustainable energy future. [ABSTRACT FROM AUTHOR]

The rapid increase in cooling demand for air-conditioning worldwide brings the need for more efficient cooling solutions based on renewable energy. Seawater air-conditioning (SWAC) can provide base-load cooling services in coastal areas utilizing deep cold seawater. This technology is suggested for inter-tropical regions where demand for cooling is high throughout the year, and it has been implemented in islands with short distances from the coast and the deep sea. This paper proposes adjustments to the conventional design of SWAC plants to reduce implementation risks and costs. The approach is named high velocity SWAC and consists of increasing the excavation depth of the seawater pump station up to 20 m below the sea level, compared to 2 to 5 m in conventional SWAC projects. This allows a twofold increase in the speed of inlet pipeline seawater and cooling load of the plant. The cooling load can be expanded twofold with only 55% capital cost and 83% project costs, compared with the costs of a new system. In addition, this article shows that high velocity SWAC plants with thermal energy storage will have an important role supporting the dissemination of intermittent renewable sources of energy in regions where SWAC is a viable cooling alternative. [ABSTRACT FROM AUTHOR]

Land use and water management have considerable impacts on regional climates. This paper proposes that in humid regions with low wind patterns the construction of hydropower storage reservoirs contributes to the increases in the probability of precipitation in the regional climate. This observation has been tested with a methodology that calculates the cumulative influence of reservoir construction in the basins surrounding with a proposed index named Cumulative Impact of Existing Reservoirs, and compares this index with the historical flow of the rivers. It was found that the construction of reservoirs in Brazil had a considerable impact on its river flows. [ABSTRACT FROM AUTHOR]

Sea levels have been rising at an increasing rate in the past decades, due to the increased ocean temperatures and glacier melt caused by global warming. The continued increase in sea levels will result in large-scale impacts in coastal areas as they are submerged by the sea. Locations not able to bear the costs of implementing protection and adaptation measures will have to be abandoned, resulting in social, economic, and environmental losses. The most important mitigation goal for sea level rise is to reduce or possibly revert carbon dioxide (CO2) emissions. However, given the magnitude and long time lag between emissions and impacts, new adaptation measures to reduce sea level rise should be proposed, developed and if possible, implemented. This paper suggests that submerged barriers or dams built in front of ice sheets and glaciers would contribute to reducing the ice melt in Greenland. The ten proposed barriers or dams in this paper could prevent the contribution to sea level rise by up to 5.3 m at a cost of US$ 0.275 billion a year. This is much lower when compared to adaptation measures to sea level rise around the world estimated to be US$ 1.4 trillion a year by 2100. [ABSTRACT FROM AUTHOR]