The worldwide lowest specific energy consumption measured in a seawater desalination plant – Real integration and opportunities of improvement Baltasar Peñate-Suarez, Juan Antonio de la Fuente-Bencomo, Gustavo Melián-Monroy, Sigrid Y. Arenas Urrea, Rafael González-Almenara, Lourdes García-Rodríguez Energy Conversion and Management X, 2026 •Desalination plant with 2,500 m3/d and 1.794 kWh/m3 of specific energy consumption.•New concept of DESALRO 2.0® Guinness World Record (GWR) holder (February 2025).•Experimental assessment of an advanced SeaWater Reverse Osmosis (SWRO) demo plant.•Combining positive displacement pumps and high efficient energy recovery devices.•Optimisation of the SWRO rack coupling different models of membrane elements. This paper presents the most energy efficient 2,500 m 3 /d desalination plant using seawater reverse osmosis (SWRO) technology, referred to as DESALRO 2.0®, which has achieved the Guinness World Record (GWR) with an Specific Energy Consumption (SEC) of 1.794 kWh/m 3 (February 2025) with 40% of recovery rate and an appropriate product water quality (TDS < 200 mg/L, B < 1 mg/L). It is located at ITC − DESAL+ LIVING LAB facilities in Pozo Izquierdo (− Canary Islands, Spain) – 37 g/L, 22°C, B < 1 mg/L −. The Canary Islands Institute of Technology (ITC) developed the design of the plant whereas the temporary joint venture Canaragua-Elmasa carried out the plant construction. The design has been scaled up to 5,000 m 3 /d. DESALRO 2.0® plant is based on an advanced SWRO rack implemented with commercial products. The system consists in feed water pressurisation by means of positive displacement high-pressure pumps (HPP) working in parallel, along with two isobaric chambers as energy recovery device (ERD) and a booster pump. Besides, an optimised design of the RO membranes inside the pressure vessels includes different models of membrane elements (hybrid internal design). Finally, the hydraulic design of the plant minimises the pressure losses.
Experimental assessment of a zero liquid discharge system driven by a micro gas turbine Rafael González-Almenara, Lourdes García-Rodríguez, David Sánchez Journal of Water Process Engineering, 2025 This study presents an experimental proof of concept for a zero liquid discharge (ZLD) system applied to seawater desalination. The system concentrates brine through direct-contact heat exchange using the exhaust gases of a solar micro gas turbine, bubbling them through the brine from a reverse osmosis (RO) unit until a dry residue is obtained. The design phase initially involved a hydraulic evaluation to assess gas stream-brine interactions, using a cold air stream to test different configurations and define the working region. Once hot exhaust gases were introduced, preliminary findings guided the correct sizing and internal arrangement of the ZLD system. Initial tests employed low-cost materials to successfully achieve zero liquid discharge. To fully characterise the thermo-chemical performance, experiments were conducted in batches, even though the process would operate continuously in real applications. After validating the proof of concept, the setup was refined, addressing key aspects such as material selection and optimised geometries to enhance durability and performance. • Sustainability in solar desalination: achieving ZLD and lower exhaust temperatures • Experimental proof of concept of a ZLD system for seawater desalination • Brine concentration by bubbling micro gas turbine exhaust gases • Exhaust stream completely free of salts, enabling easy salt recovery
USING HYDROGEN FOR THE GENERATION OF NON-PROPULSIVE ENERGY IN CIVIL AVIATION - DESIGN AND PERFORMANCE OF COMBINED MICRO GAS TURBINE AND ORGANIC RANKINE CYCLE SYSTEMS Alejandro Arenas-Fernández, Pablo Rodríguez-de Arriba, Antonio Escamilla-Perejón, Rafael González-Almenara, David Sánchez Proceedings of the ASME Turbo Expo, 2024 The interest in using hydrogen for civil aircraft propulsion is well known and has already been explored by the aero industry extensively. In this context, Iron NPE is a 25 M€ project funded by the Government of Spain with the aim to develop an efficient, flexible and compact generator of non-propulsive energy running on hydrogen. Aiming to achieve very high efficiency by exploiting the favourable boundary conditions at flight altitude ambient temperature as low as −65°C), micro combined cycle systems are explored as an alternative to the more standard solution based on PEM fuel cells. These systems deliver a stream of hot gases which is harvested by a bottoming Organic Rankine Cycle system downstream, to further enhance global performance. This paper presents a preliminary analysis to benchmark the generation of non propulsive energy based on fuel cells, explore the thermodynamic potential of stand-alone of micro gas turbines with small and large recuperators and assess the benefits of sacrificing micro gas turbine performance in order to enhance waste-heat-to-power recovery in a bottoming organic Rankine cycle. Key aspects of the independent systems involved as well as the integrated combined system are assessed. Eventually, it is revealed that the utilisation of combined systems with bottoming ORC units running on either propane or isobutane enable close to 50% conversion efficiency. Moreover, even if the efficiency attained by the system incorporating a bottoming isobutane ORC system is slightly higher, it seems that adopting a subcritical ORC unit running on propane allows for easier and more compact design of components at minimum performance drop.
Market Opportunities of Water Treatments Powered by Solar Micro Gas Turbines: Chile and Ecuador Case Studies Blanca Petit, Eva Sánchez-Carceller, Jesús Montes-Sánchez, Rafael González-Almenara, David Sánchez Processes, 2022 Throughout the last decades the developments on desalination field have been focused on energy consumption and costs reduction. However, water recovery and brine disposal are becoming a matter of concern to desalination industry. In this work, a Zero Liquid Discharge (ZLD) unit coupled with a Solar Micro Gas Turbine (SMGT) system is presented to address, among others, the challenges of mining industry in remote areas, in particular, fossil fuel dependence, water availability and pollution derived from effluents disposal. As a way to assess the feasibility of the proposal, a techno-economic analysis of the application in two Southern American regions (Chile and Ecuador) of photovoltaic modules, wind turbines and Solar Micro Gas Turbines is performed. Afterwards, the main novel feature of the new system—i.e., the ZLD unit—is described and a sensitivity analysis on its functioning whilst coupled with the SMGT is carried out. The aim is to propose a preliminary design of the ZLD process. The selection of the optimal ratio between exhaust gases and brine mass flow rates is analyzed, as well as variation in inlet salinity and temperatures. Furthermore, the water which could be recovered from effluents, at the same time that the heat of exhaust gases from SMGT is harvested, is quantified. Lastly, according to the results obtained, a preliminary design of a 10 kWe rated power SMGT system, coupled to Reverse Osmosis (RO) and ZLD units, is proposed.
Supercritical Carbon Dioxide Cycles for Concentrated Solar Power Plants: A Possible Alternative for Solar Desalination Rafael González-Almenara, Pablo Rodríguez de Arriba, Francesco Crespi, David Sánchez, Antonio Muñoz, Tomás Sánchez-Lencero Processes, 2022 This manuscript investigates the supercritical carbon dioxide (sCO2) power cycle employed in the power block of concentrated solar power (CSP) plants—solar tower—as an alternative for solar desalination, developed with either distillation or reverse osmosis. This concept is investigated as a possible up-scaling of the SOLMIDEFF project, originally based on a hot-air micro gas turbine combined with a solar dish collector. For the upscaled concept, five different sCO2 cycles are considered, chosen amongst the best-performing configurations proposed in the literature for CSP applications, and modelled with Thermoflex software. The influence of ambient conditions is studied, considering two minimum cycle temperatures (35 °C and 50 °C), corresponding to Santa Cruz de Tenerife and Abu Dhabi, respectively. The results show that the low temperatures at the inlet of the heat rejection unit compromise the viability of distillation technologies. On the other hand, the high thermal efficiency achieved by these cycles, especially with the recompression and partial cooling layouts, reduces the specific energy consumption when combined with reverse osmosis (RO), below that of photovoltaic (PV)+RO. Feed-water preheating is explored as a solution to further reduce energy consumption, concluding that its actual interest is not clear and strongly depends on the location considered and the corresponding water quality standards.
