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Abstract Renewable energy sources (RES) coupled to desalination offers a promising prospect for covering the fundamental needs of power and water in remote regions, where connection to the public electrical grid is either not cost effective or not feasible, and where the water scarcity is severe. Stand-alone systems for electricity supply in isolated locations are now proven technologies. Correct matching of stand-alone power supply desalination systems has been recognized as being crucial if the system is to provide a satisfactory supply of power and water at a reasonable cost. The paper covers plants installed since 1990 on the coupling of the two technologies. The main driver promoting the take up of this technology is that water is a limiting factor for many countries in the Mediterranean region. This paper presents the two technologies, RES desalination, and describes the most promising couplings such as PV–reverse osmosis, wind-mechanical-vapor compression, geothermal-multieffect distillation, etc as well as technologies selection guidelines. Also, included applications and lessons learned from specific applications as well as data on the economics. RES for desalination is an important challenge and useful work has been done. However in order to provide practical viable plants, much remains to be done.

Abstract As covering layers, barrier envelopes of VIPs are always exposed to severe environmental conditions, including high temperatures, alkaline environments and local stress concentration when used as thermal insulation material in concrete structures. This study investigated the time-dependent degradations of three types of commonly used envelopes (aluminium film, metallized film and metallized film coated with alkali-resistant (AR) fibreglass mesh) and VIPs covered by these three envelopes by simulating environmental conditions with four types of alkaline solutions (NaOH solution with pH = 7, 11, 13 and saturated Ca(OH)2), two different temperatures (20 °C and 60 °C) and local stress concentration. The results showed that stress and high temperature accelerated the degradation of envelopes and that such degradation became more serious with increased pH value and temperature. It was also observed that the thermal conductivity of VIPs increases quickly when they are exposed to higher alkalinity combined with high temperatures. After 6-week submerged in saturated Ca(OH)2 solution at 60 °C, the thermal conductivity of VIPs increased from 4.413 mW/m K to 13.049 mW/m K for aluminium foil, from 5.375 mW/m K to 10.982 mW/m K for metallized film, and from 5.786 mW/m K to 8.110 mW/m K for AR fibreglass mesh-reinforced film, respectively.

SummaryStudies investigated the patient‐care (in‐hospital) and outside‐the‐hospital energy consumptions for delivering the hemodialysis (HD) service. A life cycle inventory methodology was used for this patient‐based analysis for two hospitals located in Wichita, Kansas. It was found that, for both hospitals, the actual HD machines consumed approximately 3.5 kilowatt‐hours (kWh) of electrical energy per HD, only 8% to 16% of the total energy used for delivering the HD service (in hospital). This increases to 9.6 to 28.9 kWh of hospital billable energy for the whole system of HD machine, auxiliaries, and dialysis water treatment. Converting these hospital direct electrical energy values to natural resource energy (nre) then adding the cradle‐to‐gate natural resource energy for the manufacturing and supply chain of all the HD consumables, the total is 78 to 149 kWh nre/HD. The nre measures all the direct fuel burned to generate energy and is thus directly related to emissions to the air, water, and land and is a direct secondary impact on public health from HD. The ratio of outside‐the‐hospital energy to direct hospital HD electrical energy consumption is 4:1 to 7:1, so a broader base exists for improvement than just the hospital.

Abstract Recent results of GDF SUEZ Research and Innovation Division (RID) activities on Compressed Natural Gas (CNG) vehicles are depicted in this paper: • The prototype “Toyota Prius II Hybrid CNG Vehicle”, developed with IFP Energies Nouvelles, combines a natural gas thermal engine with a hybrid electric motorization. After optimization, CO2 emissions, measured on chassis dynamometer, were 76 g/km on NEDC cycle. • The use of raw biogas in CNG Vehicle has been explored. These tests have shown that raw biogas (not upgraded) can be used as a fuel, if blended with natural gas. In fact, the use of raw biogas can be envisaged in dedicated CNG engines, if new engine technologies (lean CNG combustion) are developed. In such a case natural gas can be blended with up to 70% volume of not upgraded biogas. • The potential reduction of greenhouse gases (GHG) emissions related both to the optimization of the CNG vehicle and to the use of biomethane as a vehicle fuel has been evaluated. GHG emissions from CNG vehicles (mono-fuel and hybrid) may be significantly lower than emissions of gasoline vehicles: around 17% lower in the case of dedicated CNG Vehicle and up to 51% lower in the case of hybrid CNG vehicles. In addition, biomethane (from the anaerobic digestion of waste) brings the GHG emission levels, over the course of the life cycle, down to more than 80% compared to a gasoline vehicle. Emission levels are lowered by 87% in the case of the Toyota Prius CNG Hybrid prototype fuelled by biomethane produced from waste (in comparison to a gasoline vehicle). Thus, biomethane allows a reduction of GHG emissions far below the minimum required by the European Directive on the Promotion of Renewable Energy Sources (2009/28/EC). These results have shown that the combination of optimized and innovative engines with the use of biomethane as a fuel permits to significantly reduce the GHG emissions.

The objective of this study was to determine effects of drought on selected root growth parameters and develop relationships between root parameters and tuber yield for selected Jerusalem artichoke (JA) genotypes. Three water regimes (Field capacity, 50% available soil water (AW) and 25% AW) and five JA varieties (JA 60, JA 125, JA 5, JA 89 and HEL 65) were planted with factorial treatments in a randomized complete block design with four replications. Data on root dry weight (RDW) and root: shoot ratios (RSR) were measured manually. Root diameter (RD), root length (RL), root surface area (RSA) and root volume (RV) were collected at harvest. Drought tolerance indices (DTI) were calculated for all root parameters. Drought reduced all root parameters and DTI but increased RSR in JA 60, JA 125, JA 5, and HEL 65. JA 125 had high values for all root traits and DTI of these traits under drought stress. JA 60 had high DTI of RDW, RD and RSR under mild and severe water stress. JA 5 had high DTI of RDW, RD, RL, RSR and RV under drought conditions. JA 89 and HEL 65 performed well for RDW, RD, RL and low DTI of all root characteristics. DTI for root parameters were positively correlated with tuber dry weight under mild and severe water stress. The JA 5, JA 60 and JA 125 varieties showed high DTI for some root traits, indicating that better root parameters contributed to higher tuber yield under drought stress.

Abstract In this paper, we examine the time-varying causal relationship between green bonds and other assets including US conventional bonds, WilderHill clean energy (equity) index, and CO2 emission allowances price during the period spanning from 30 July 2014 to 10 February 2020. We apply the novel time-varying Granger causality test (Shi et al. 2018) based on the recursive evolving algorithm introduced by Phillips et al. (2015a, 2015b) for controlling financial bubbles to detect real–time causality, detecting possible changes in the causal direction and dating financial turbulences, The study based on this algorithm reveals a significant causality running from the US 10-year Treasury bond index to green bonds starting from the end of the year 2016 until the end of the sample period. Besides, we find that the link CO2 emission allowances price causing green bonds is significant from the beginning of the sample period to the end of the year 2015. Furthermore, by using the recursive-evolving causality algorithm of the Shi et al. (2018) test, we find that the causality running from the clean energy index to green bonds is very limited to the year 2019. On the other hand, there is no significant causality running from green bonds to all considered assets, indicating no predictive power for this asset in its proper domain, which is not yet examined in the literature.

Deposits formation on heat transfer surfaces is one of the main problems associated to biomass co-combustion. It reduces plant efficiency and availability and increases maintenance costs. It is obvious that an increasing amount of low-temperature melting components in fuel ash accelerates and aggravates this process. Research is done to evaluate the validity of thermal analysis methods to characterise fusion of biomass and waste ashes. Laboratory ashes from a set of biomass and waste fuels are leached in successive steps. The original and the leached ashes are analysed by Thermo-Mechanical Analysis (TMA). Traces obtained from TMA show to be promising ash fingerprints to classify deposition tendencies. Additionally Simultaneous Thermal Analysis (STA) is performed on selected samples. Furthermore, improved chemical equilibrium calculations are proposed to predict the proportion of melted species resulting from combustion of biomass fuels. The model takes into account the reactivity of the inorganic matter in the fuel as issued from ash leaching.

The Commonwealth of Massachusetts has played a significant role in deploying renewable energy in the United States. In 2013, former Governor Deval Patrick announced an ambitious state goal of 1.6 GW of solar generation to be installed by 2020. This announcement was made after the state achieving its goal of 250 MW of solar energy four years early. The current governor, Charlie Baker, and his administration have also been very ambitious to reduce the greenhouse gas emissions.

Abstract There is a growing need for drop-in biofuels for gas turbines for enhanced energy security and sustainability. Several fuels are currently being developed and tested to reduce dependency on fossil fuels while maintaining performance, particularly in the aviation industry. The transition from traditional fossil fuels to sustainable biofuels is much desired for reducing the rapidly rising CO2 levels in the environment. This requires biofuels to be drop-in ready, where there are no adverse effects on performance and emissions upon replacement. In this study, the performance and emissions of four different aviation drop-in biofuels were evaluated. They include UOP HEFA-SPK, Gevo ATJ, Amyris Farnesane, and SB-JP-8. These aviation biofuels are currently being produced and tested to be ready for full or partial drop-in fuels as the replacement of traditional jet fuels. The characteristic performance of each fuel from the prevaporized liquid fuels was performed in a high-intensity (20 MW/m3-atm) reverse flow combustor. The NO emissions showed near unity ppm levels for each of the fuels examined with a minimum at an equivalence ratio of ∼0.6, while CO levels were in the range of 1000–1300 ppm depending on the fuel at an equivalence ratio between 0.75 and 0.8. For an equivalence ratio range between 0.4 and 0.6, NO and CO emissions remained very low (between 1–2 ppm NO and 2400–2900 ppm CO) depending on the fuel. The examined biofuels did not show any instability over a wide range of equivalence ratios from lean to near stoichiometric condition. These results provide promising results on the behavior of these drop-in aviation biofuels for use in high-intensity gas turbine combustors providing stability and cleaner performance without any modification to the combustor design.