Thermoeconomic and stability analysis of the salinity gradient of Solar Pond technology: Industrial case of study.

Solar pond is a technology capable to capture and store solar energy. The system is also capable to provide thermal energy to an industrial application. In this project a stability and a thermoeconomic analyses of an industrial solar pond are carried out to study its thermal performance

Stability analysis of an industrial salinity gradient solar pond

In this study, an assessment of salinity gradient stability of an industrial solar pond during two operation seasons (2014 and 2105) is presented. An industrial solar pond was constructed to supply a low-temperature heat (up to 60¿°C) to achieve the temperature requirements of the flotation stage in a mineral processing plant (Solvay Minerales in Granada (Spain)). Along the first season, the salinity gradient was considered technically destroyed in April 2015 as the height to the upper convective zone increases from 0.3¿m in July 2014 to 0.8¿m. Two different methodologies based on the stratification principle were adapted and used in order to evaluate the salinity gradient stability. The boundaries of the salinity gradient appeared as the main source of instability. In the upper zone it is associated with the environmental parameters (e.g., rain and wind) that affect the upper convective zone and the upper layers of the non-convective zone that subsequently transmit the instability to the lower layers. In the bottom zone it is caused by operation parameters, such as the heat extraction or the addition of salt. Both methodologies provided similar predictive capability of stability results. However, the results provided by the stability analysis using the thermal and salinity expansion coefficients are a more useful tool in the control of the salinity gradient for solar pond technology.Peer ReviewedPostprint (published version

Design, construction, and operation of the first industrial salinity-gradient solar pond in Europe: An efficiency analysis perspective

A 500 m2 industrial salinity-gradient solar pond (SGSP) was constructed in a mineral processing plant (Solvay Minerales) in Granada (Spain). This renewable energy technology was designed to supply a low-temperature heat (up to 60 °C) to achieve the temperature requirements of the flotation mineral purification stage. The low-temperature source was integrated to partially replace the fuel oil boiler used to heat the water used in the flotation stage. Theoretical calculations based on solar radiation indicated that the use of the SGSP would reduce the annual fuel consumption by more than 50%, thus providing a significant improvement at both economic and environmental levels. Two months after the SGSP was established, in August 2014, the temperature in the storage zone of the SGSP reached approximately 90 °C. The overall performance was evaluated in two periods (2014 and 2015) in terms of the retrofitting of mining facility with a solar pond and a new method to assess the thermal efficiency of the solar pond in a long-term perspective has been proposed. The overall efficiencies obtained after the first and second operation periods were 10 and 12%, respectively, with maximum values of 28 and 24% obtained during the first operation months. Regarding the economic savings, the fuel oil cost of the flotation unit was reduced by a higher percentage than the fuel oil consumption, due to the decreasing tendency of fuel oil prices during 2014 and 2015. Reductions of 52 and 68% were obtained in the first and second periods of operation, respectively, when compared to 2013. In addition, not only does the SGSP have considerably reduced operating costs but also the environmental costs are clearly reduced when considering the reduction of CO2 emissions.Peer ReviewedPostprint (author's final draft

Assessing the 2014 retroactive regulatory framework applied to the concentrating solar power systems in Spain

The RD 413/2014 new economic and regulatory framework applied to the concentrating solar power plants (CSPP) in Spain has been here analysed and its new remuneration scheme has been formulated, becoming evident its high complexity and the great number of regulatory parameters involved. Next, a new model focused on determining its impact on the economic results of the existing CSPP has been proposed. Due to the complexity of the system, a methodology comprising a set of different stages of analysis has been developed. The new model has proven to be a useful tool to analyse the economic impact of the new regulatory scheme on the facilities and to identify its most influential regulatory parameters. One of the most representative facilities has been chosen as a case study to undertake the analysis. The results of the analysis, which have shown a substantial profitability reduction, have been consistent with the appreciations and data provided by the claimants of the last arbitral Award concerning the Kingdom of Spain and investors of CSPP in this country.Peer ReviewedPreprin

Contribution to the remuneration of regulated activities in Spanish Electricity Sector. Focusing on Renewable Energies

En aquest projecte s’ha realitzat un profund anàlisis de la legislació espanyola que regula les centrals elèctriques d’energies renovables. El principal objectiu d’aquest document és analitzar com els canvis més recents en la legislació han afectat aquest tipus d’instal·lacions. Amb la finalitat de poder presentar una anàlisis més concret s’ha considerat oportú centrar-se en un sol sector dins la generació renovable. El sector escollit ha estat el termosolar. A través d’aquest sector el lector descobrirà teòricament i matemàticament tots els marcs reguladors aprovats pel govern en els últims anys. A més, també serà estudiat l’impacte que tots aquests canvis han tingut en la rendibilitat de les instal·lacions termosolars així com en l’economia estatal. Finalment, el projecte inclou un estudi exhaustiu del estalvi en el cost mediambiental que suposa aquest tipus de centrals generadores

Thermoeconomic and stability analysis of the salinity gradient of Solar Pond technology: Industrial case of study.

Solar pond is a technology capable to capture and store solar energy. The system is also capable to provide thermal energy to an industrial application. In this project a stability and a thermoeconomic analyses of an industrial solar pond are carried out to study its thermal performance

Contribution to the remuneration of regulated activities in Spanish Electricity Sector. Focusing on Renewable Energies

En aquest projecte s’ha realitzat un profund anàlisis de la legislació espanyola que regula les centrals elèctriques d’energies renovables. El principal objectiu d’aquest document és analitzar com els canvis més recents en la legislació han afectat aquest tipus d’instal·lacions. Amb la finalitat de poder presentar una anàlisis més concret s’ha considerat oportú centrar-se en un sol sector dins la generació renovable. El sector escollit ha estat el termosolar. A través d’aquest sector el lector descobrirà teòricament i matemàticament tots els marcs reguladors aprovats pel govern en els últims anys. A més, també serà estudiat l’impacte que tots aquests canvis han tingut en la rendibilitat de les instal·lacions termosolars així com en l’economia estatal. Finalment, el projecte inclou un estudi exhaustiu del estalvi en el cost mediambiental que suposa aquest tipus de centrals generadores

Thermoeconomic and stability analysis of the salinity gradient of Solar Pond technology: Industrial case of study.

Solar pond is a technology capable to capture and store solar energy. The system is also capable to provide thermal energy to an industrial application. In this project a stability and a thermoeconomic analyses of an industrial solar pond are carried out to study its thermal performance

Stability analysis of an industrial salinity gradient solar pond

In this study, an assessment of salinity gradient stability of an industrial solar pond during two operation seasons (2014 and 2105) is presented. An industrial solar pond was constructed to supply a low-temperature heat (up to 60¿°C) to achieve the temperature requirements of the flotation stage in a mineral processing plant (Solvay Minerales in Granada (Spain)). Along the first season, the salinity gradient was considered technically destroyed in April 2015 as the height to the upper convective zone increases from 0.3¿m in July 2014 to 0.8¿m. Two different methodologies based on the stratification principle were adapted and used in order to evaluate the salinity gradient stability. The boundaries of the salinity gradient appeared as the main source of instability. In the upper zone it is associated with the environmental parameters (e.g., rain and wind) that affect the upper convective zone and the upper layers of the non-convective zone that subsequently transmit the instability to the lower layers. In the bottom zone it is caused by operation parameters, such as the heat extraction or the addition of salt. Both methodologies provided similar predictive capability of stability results. However, the results provided by the stability analysis using the thermal and salinity expansion coefficients are a more useful tool in the control of the salinity gradient for solar pond technology.Peer Reviewe

Assessing the 2014 retroactive regulatory framework applied to the concentrating solar power systems in Spain

The RD 413/2014 new economic and regulatory framework applied to the concentrating solar power plants (CSPP) in Spain has been here analysed and its new remuneration scheme has been formulated, becoming evident its high complexity and the great number of regulatory parameters involved. Next, a new model focused on determining its impact on the economic results of the existing CSPP has been proposed. Due to the complexity of the system, a methodology comprising a set of different stages of analysis has been developed. The new model has proven to be a useful tool to analyse the economic impact of the new regulatory scheme on the facilities and to identify its most influential regulatory parameters. One of the most representative facilities has been chosen as a case study to undertake the analysis. The results of the analysis, which have shown a substantial profitability reduction, have been consistent with the appreciations and data provided by the claimants of the last arbitral Award concerning the Kingdom of Spain and investors of CSPP in this country.Peer Reviewe