Ana I. Palmero-Marrero

Comparison of solar thermal technologies for applications in seawater desalination

This paper deals with a global analysis of the use of solar energy in seawater distillation under Spanish climatic conditions. Static solar technologies as well as one-axis sun tracking were compared. Different temperature ranges of the thermal energy supply required for a desalination process were considered. At each temperature range, suitable solar collectors were compared in some aspects as: (1) fresh water production from a given desalination plant; (2) attainable fresh water production if a heat pump is coupled to the solar desalination system; (3) area of solar collector required for equivalent energy production. Results showed that direct steam generation (DSG) parabolic troughs are a promising technology for solar-assisted seawater desalination.

Application of direct steam generation into a solar parabolic trough collector to multieffect distillation

Abstract In this paper, the application of the direct steam generation into a solar parabolic trough collector to multieffect distillation is proposed and economically evaluated. The thermal fluid of the solar field is pure water, which boils as circulating along the solar collectors. The steam generated drives a multieffect distillation unit. This solar distillation system is compared with multieffect plants connected to a conventional parabolic trough collector field, and with fossil fuel powered distillation plants. Different parameters are analysed, the plant capacity and performance ratio, the cost of conventional thermal energy, the cost of the solar collectors, and the annual average of the fresh water obtained per m 2 of solar collector. Results obtained are useful in finding the most suitable conditions in which solar energy could compete with conventional energies in solar desalination.

Thermoeconomic optimization of the SOL-14 plant (Plataforma Solar de Almería, Spain)

The Sol-14 plant is a solar multi-effect distillation system installed at the Plataforma Solar de Almeria, a solar research centre located in southeastern Spain, near Almeria. In July 1988 the first start-up of the plant took place, which was connected to the previous existing solar facilities. In the second phase of the project, a double-effect absorption heat pump (DEAHP) was coupled to the MED plant that was already installed. Results of the thermoeconomic analysis performed show direct steam generation (DSG) parabolic troughs exhibit great potential for improving the Sol-14 plant. Replacing the oil-based technology by DSG presents many advantages from the point of view of thermodynamics, environmental hazards of oils, land use, use of materials or lifetime of the solar collectors.

Comparison of software prediction and measured performance of a grid-connected photovoltaic power plant

In this work, the performance of a photovoltaic (PV) installation is assessed. The plant consists of a grid-connected centralized system, where the supplied power is not associated with a particular electricity customer. Operational data from this PV plant, ground-mounted and located in the north of Portugal, are now available for a period of 3 years. The plant is equipped with PV modules (amorphous Si cells), with 60 Wp per module, and a total generating capacity of 124.2 kWp. In this installation, 24 inverters are used. To obtain an accurate prediction of the efficiency and power output, the characteristics of all plant components were introduced in the PVsyst software and TRNSYS software, together with meteorological data: either those collected at a local meteorological station or those provided by Meteonorm. The results obtained through the simulations and the measured output power values were compared. The results showed that both PVsyst and TRNSYS seem to be good tools to predict the annual electri...

Testing of an integrated solar louvre collector

SYNOPSIS The integration of solar collectors into louvres has been studied. An existing louvre design was modified to integrate a solar collector in the shading device. This solar louvre collector has been experimentally tested under real outside conditions, during Summer and Winter seasons. Experimental results were compared to numerical ones, and a good agreement was obtained.

Research on heating and cooling requirements of buildings with solar louvre devices

Abstract External louvres have been increasingly used to provide solar protection for a buildings glazed surfaces. In this work, a general study of the effect of louvre shading devices applied to different façades of a building is carried out for different locations (latitudes). Building energy requirements for a building in the cooling and heating seasons are quantified for different window and louvre areas, under different climatic conditions (Europe, Africa and America). Shading geometry is studied with EES software, while indoor air and operative temperatures are calculated through simulations with TRNSYS. Both horizontal and vertical louvre layouts are considered. The results show that the use of louvre shading devices in the building leads to indoor comfortable thermal conditions and may lead to significant energy savings, in comparison with a building without shading devices. The potential of integrating solar thermal collectors into horizontal solar louvres is also addressed, by considering possible active solar heating and cooling systems.

Evaluation of a solar louvre collector system for building heating and cooling

SYNOPSIS In this work, the application of a solar louvre collector system for building heating and cooling is studied. The system operates either in cooling mode, coupled to a water-fired absorption chiller, or in heating mode, when hot water is circulated through the slab (radiant heating). A mono-zone building, with an area of 100 m2, was used as a case study, in order to assess the performance in both operating modes. The system was modelled with the TRNSYS simulation program, under the climatic conditions of Portugal. Results show that the application of solar louvre collectors to building heating and cooling is viable and interesting, leading to energy and emissions savings when compared with conventional solutions. Viable simple payback times were calculated for the system, for both heating alone and cooling/heating modes.

Energetic Analysis of the Implementation of Renewable Energies in a Canary Island Hotel

The European Directive on Energy Performance of Buildings has established a target of Nearly Zero-Energy Buildings (nZEB) for a sustainable future. For this target, hotels take a special interest, as shown in the neZEH project (Nearly Zero Energy Hotels project) (neZEH, 2016), (Tsoutsos et al., 2013). In this work, a hotel located in Tenerife (Canary Island, Spain) is analyzed. With the objective of reaching the nZEB label, an exhaustive energetic analysis of the hotel was performed and the implementation of different renewable energy systems was proposed. The utilization of solar thermal collectors, photovoltaic collectors and heat pumps are analyzed in this work. Also, the passive solar characteristics, namely related to internal shading, were considered.