Electricity consumption is rising due to population growth, climate change, urbanization, and the increasing use of electronic devices. The trend of the Internet of Things has contributed to the creation of devices that promote the thrift and efficient use of electrical energy. Currently, most projects relating to this issue focus solely on monitoring energy consumption without providing relevant parameters or switching on/off electronic devices. Therefore, this paper presents in detail the design, construction, and validation of a smart meter with load control aimed at being part of a home energy management system. With its own electronic design, the proposal differs from others in many aspects. For example, it was developed using a simple IoT architecture with in-built WiFi technology to enable direct connection to the internet, while at the same time being big enough to be part of standardized electrical enclosures. Unlike other smart meters with load control, this one not only provides the amount of energy consumption, but rms current and voltage, active, reactive, and apparent power, reactive energy, and power factor—parameters that could be useful for future studies. In addition, this work presents evidence based on experimentation that the prototype in all its readings achieves an absolute percentage error of less than 1%. A real-life application of the device was also demonstrated in this document by measuring different appliances and switching them on/off manually and automatically using a web-deployed application.

This study conducts a numerical comparison of the thermal performance of three distinct working fluids (pure water, TiO₂, and SiO₂ water-based nanofluids) within an evacuated tube solar collector using Computational Fluid Dynamics. The study evaluates thermohydraulic performance alongside global and local entropy generation rates, while considering variations in solar radiation values and inlet mass flow rates. Results indicate that nanofluids demonstrate superior performance under low solar radiation, exhibiting higher outlet temperatures, velocities, thermal efficiency, and exergy efficiency compared to pure water. However, at the higher solar radiation level, the efficiency of SiO₂ water-based nanofluid diminishes due to its impact on specific heat. Furthermore, the entropy generation analysis reveals significant reductions with TiO₂ water-based nanofluid in all the phenomena considered (up to 79 %). The SiO₂ nanofluid performance aligns closely with pure water under high radiation value. This investigation offers valuable insights into the utilization of nanofluids in solar collectors across diverse operating conditions, emphasizing their pivotal role in enhancing overall performance.

The energy consumption for space cooling is growing faster than for any other end-use in buildings, more than tripling between 1990 and 2016. Energy efficiency is an important topic in the drive to reduce the consumption of electricity, particularly in air conditioning. This paper presents a simulation of an absorption cooling system with a parabolic trough collector under dynamic conditions using TRaNsient SYstem Simulation (TRNSYS) software. The thermal analysis seeks to evaluate a storage tank at three different configurations: (1) sensible heat, (2) latent heat, and (3) latent heat incorporating a tempering valve. The latent heat storage tank is a rectangular heat exchanger using MgCl₂·6H₂O as the phase change material, programmed in EES software; in addition, water and synthetic organic fluid were analyzed as heating fluids. The process was analyzed while varying the solar collector area from 20 to 40 m² and the storage tank volume from 0.25 to 0.75 m³. The results showed that the solar collector of configuration 1 is unable to satisfy the energy demand. Configuration 2 can satisfy the demand with water and a storage tank volume above 0.50 m³ and 30 m², while configuration 3 can satisfy the demand above 0.50 m³ and 20 m² with water.