Seawater desalination in micro grids: an integrated planning approach

Background: Islands often depend on the import of fossil fuels for power generation. Due to the combined effect of high oil prices and transportation costs, energy supply systems based on renewable energies are already able to compete successfully with fossil fuel systems for a number of these islands. Depending on local and regional conditions, not only energy supply is a challenge, but also the finding of a reliable supply of water. A promising alternative to freshwater shipments is seawater desalination. Desalination processes can act as a flexible load whenever excess electricity generated by renewable sources is present. Methods: Numerical simulations of combined energy and water supply systems for the Caribbean island Petite Martinique, Grenada, are accomplished. Considering renewable energy sources like wind and solar radiation, energy storage technologies, and desalination processes, various scenarios are introduced and simulated, and the results are compared. Results: An extension of the current energy supply system with renewable energy technologies reduces power generation costs by approximately 40%. The excess energy generated by renewables can supply a significant share of a desalination plant’s energy demand. The levelized costs of electricity and water show that the integration of desalination as a deferrable load is beneficial to the considered micro grid. Conclusions: The implementation of renewable energy generation and desalination as deferrable load is recommendable in Petite Martinique. Possible refinancing strategies depending on the combination of different electricity and water tariffs can be derived and applied to similar business cases in remote regions

Desalination and sustainability: a triple bottom line study of Australia

For many arid countries, desalination is considered as the final possible option to ensure water availability. Although seawater desalination offers the utilisation of almost infinite water resources, the technology is associated with high costs, high energy consumption and thus high carbon emissions when using electricity from fossil sources. In our study, we compare different electricity mixes for seawater desalination in terms of some economic, social and environmental attributes. For this purpose, we developed a comprehensive multi-regional input-output model that we apply in a hybrid life-cycle assessment spanning a period of 29 yr. In our case study, we model desalination plants destined to close the water gap in the Murray-Darling basin, Australia's major agricultural area. We find that under a 100%-renewable electricity system, desalination consumes 20% less water, emits 90% less greenhouse gases, and generates 14% more employment. However, the positive impacts go hand in hand with 17% higher land use, and a 10% decrease in gross value added, excluding external effects.TU Berlin, Open-Access-Mittel – 202

Electrification of waste collection vehicles: Techno-economic analysis based on an energy demand simulation using real-life operational data

Waste transport plays an important role in the decarbonization of the transport sector. In this paper diesel-powered (dWCV) and electric waste collections vehicles (eWCV) and their operation are analysed regarding energy demand and total cost of ownership (TCO) integrating Well-to-Wheel emission costs. Further, an open-source simulation tool with a route synthetization approach is presented using extensive real-life operational data of five different route types. Determined WCV energy demand varies greatly between vehicle topologies and analysed route types. eWCV show a mean distance-specific energy demand of 1.85 kWh·km-1, while values for dWCV increase to 5.43 kWh·km-1 respectively. The factors route distance and number of waste containers collected show the highest influence on results. Therefore, battery capacity should be sized according to specific route types. eWCV show higher TCO than dWCV under current economic constraints but fuel price level and annual vehicle mileage show a high influence on economic feasibility. Taking the planned emissions price mechanism of the German Government into account, economic scenarios could be identified, which make eWCV advantageous yet in 2021. In technical terms, there is nothing to stop for the electrification of WCV, and with suitable political instruments eWCV could become profitable in the short-term

Economic benefits through system integration of electric waste collection vehicles: Case study of grid-beneficial charging and discharging strategies

Electrification of a waste collection fleet as part of vehicle-to-grid can be used in a grid- beneficial way, which in turn can increase the economy of these vehicles. In this study the system and grid integration of fully battery-electric waste collection vehicles (eWCV) is examined. The possibility to shave power peaks of a lightweight packaging plant and to provide balancing power by eWCV are analyzed. For this, performance and market models are developed using an ex-post analysis, considering also levies and charges. Building on this, various scenarios for the grid-beneficial integration of eWCV are designed. These are assessed based on the resulting energy consumption of the eWCV, charging costs and feasibility for real-life implementation. It is shown that using electricity generated by thermal waste management plants for charging can reduce the operation costs of eWCV. Also, peak shaving is viable from an economic point of view. Network charges and well as the complexity of the system prevent an economical provision of balancing power by eWCV

Wirkungsanalyse der Mykorrhiza-komponente in Kombination mit Düngemitteln in Lysimeterversuchen

In Lysimeterversuchen mit unterschied-lichen Energiepflanzen (Sonnenblumen, Steinklee, Zuckerhirse) und verschied-enen Grundwasserständen wurde der Einfluss einer Beimpfung mit einem kommerziellen Mykorrhizapräparat (CUXIN -Inokulum) auf Wassereffizienz und Biomassebildung dieser Pflanzen unter-sucht. Die unterschiedlichen Pflanzen- arten reagierten nicht einheitlich auf eine Beimpfung mit Mykorrhiza. Unterschiedlich waren auch der Wasserverbrauch und die verdunstete Wassermenge in Abhängigkeit von der Mykorrhizierung. Die Ergebnisse dieser Lysimeterversuche machen deut-lich, wie stark Ertrag und Wassereffizienz von Nutzpflanzen durch das Zusammen-wirken von Pflanzenarten, Böden, Grund-wasserständen und der Mykorrhizierung bestimmt wird. Insbesondere bei Sonnenblumen ließen sich signifikant positive Effekte durch Mykorrhizabehandlung nachweisen

Characteristics of Smoldering on Moist Rice Husk for Silica Production

In order to assess the possibility of silica production via smoldering of moist rice husk, experiments of washed (moist) rice husk (7 kg with moisture content of 51%) in a newly designed smoldering apparatus was performed. The temperature inside the fuel bed during smoldering was recorded, and characteristics of ash were analyzed. Results showed that the highest temperature in the middle of the naturally piled fuel bed was about 560.0 °C, lower than those in most of combustors. Some volatiles from the lower part of the fuel bed adhere to its upper ash during piled smoldering. Silica content and specific surface area of ash from smoldering of washed (moist) rice husk were 86.4% and 84.9 m2/g, respectively. Compared to our experiments, they are close to smoldering of unwashed rice husk (89.0%, 67.7 m2/g); different from muffle furnace burning (600 °C, 2 h) of washed (93.4%, 164.9 m2/g) and un-washed (90.2%, 45.7 m2/g) rice husk. The specific surface area is higher than those from most industrial methods (from 11.4 to 39.3 m2/g). After some improvements, the smoldering process has great potential in mass product of high quality silica directly from moist rice husk

Influence of Plasma-Isolated Anthocyanins and Their Metabolites on Cancer Cell Migration (HT-29 and Caco-2) In Vitro: Results of the ATTACH Study

Cancer mortality is mainly due to metastasis. Therefore, searching for new therapeutic agents suppressing cancer cell migration is crucial. Data from human studies regarding effects of anthocyanins on cancer progression, however, are scarce and it is unclear whether physiological concentrations of anthocyanins and their metabolites reduce cancer cell migration in vivo. In addition, interactions with chemotherapeutics like 5-fluorouracil (5-FU) are largely unknown. Thus, we combined a placebo-controlled, double-blinded, cross-over study with in vitro migration studies of colon cancer cell lines to examine the anti-migratory effects of plasma-isolated anthocyanins and their metabolites (PAM). Healthy volunteers (n = 35) daily consumed 0.33 L of an anthocyanin-rich grape/bilberry juice and an anthocyanin-depleted placebo juice for 28 days. PAM were isolated before and after intervention by solid-phase extraction. HT-29 and Caco-2 cells were incubated with PAM in a Boyden chamber. Migration of HT-29 cells was significantly inhibited by PAM from juice but not from placebo. In contrast, Caco-2 migration was not affected. Co-incubation with 5-FU and pooled PAM from volunteers (n = 10), which most effectively inhibited HT-29 migration, further reduced HT-29 migration in comparison to 5-FU alone. Therefore, PAM at physiological concentrations impairs colon cancer cell migration and may support the effectiveness of chemotherapeutics

The challenge of measuring physiological parameters during motor imagery engagement in patients after a stroke

Introduction: It is suggested that eye movement recordings could be used as an objective evaluation method of motor imagery (MI) engagement. Our investigation aimed to evaluate MI engagement in patients after stroke (PaS) compared with physical execution (PE) of a clinically relevant unilateral upper limb movement task of the patients' affected body side. Methods: In total, 21 PaS fulfilled the MI ability evaluation [Kinaesthetic and Visual Imagery Questionnaire (KVIQ-10), body rotation task (BRT), and mental chronometry task (MC)]. During the experiment, PaS moved a cup to distinct fields while wearing smart eyeglasses (SE) with electrooculography electrodes integrated into the nose pads and electrodes for conventional electrooculography (EOG). To verify MI engagement, heart rate (HR) and oxygen saturation (SpO2) were recorded, simultaneously with electroencephalography (EEG). Eye movements were recorded during MI, PE, and rest in two measurement sessions to compare the SE performance between conditions and SE's psychometric properties. Results: MI and PE correlation of SE signals varied between r = 0.12 and r = 0.76. Validity (cross-correlation with EOG signals) was calculated for MI (r = 0.53) and PE (r = 0.57). The SE showed moderate test–retest reliability (intraclass correlation coefficient) with r = 0.51 (95% CI 0.26–0.80) for MI and with r = 0.53 (95% CI 0.29 – 0.76) for PE. Event-related desynchronization and event-related synchronization changes of EEG showed a large variability. HR and SpO2 recordings showed similar values during MI and PE. The linear mixed model to examine HR and SpO2 between conditions (MI, PE, rest) revealed a significant difference in HR between rest and MI, and between rest and PE but not for SpO2. A Pearson correlation between MI ability assessments (KVIQ, BRT, MC) and physiological parameters showed no association between MI ability and HR and SpO2. Conclusion: The objective assessment of MI engagement in PaS remains challenging in clinical settings. However, HR was confirmed as a reliable parameter to assess MI engagement in PaS. Eye movements measured with the SE during MI did not resemble those during PE, which is presumably due to the demanding task. A re-evaluation with task adaptation is suggested

Towards Biochar and Hydrochar Engineering—Influence of Process Conditions on Surface Physical and Chemical Properties, Thermal Stability, Nutrient Availability, Toxicity and Wettability

The impact of conversion process parameters in pyrolysis (maximum temperature, inert gas flow rate) and hydrothermal carbonization (maximum temperature, residence time and post-washing) on biochar and hydrochar properties is investigated. Pine wood (PW) and corn digestate (CD), with low and high inorganic species content respectively, are used as feedstock. CD biochars show lower H/C ratios, thermal recalcitrance and total specific surface area than PW biochars, but higher mesoporosity. CD and PW biochars present higher naphthalene and phenanthrene contents, respectively, which may indicate different reaction pathways. High temperatures (>500 °C) lead to lower PAH (polycyclic aromatic hydrocarbons) content (<12 mg/kg) and higher specific surface area. With increasing process severity the biochars carbon content is also enhanced, as well as the thermal stability. High inert gas flow rates increase the microporosity and wettability of biochars. In hydrochars the high inorganic content favor decarboxylation over dehydration reactions. Hydrochars show mainly mesoporosity, with a higher pore volume but generally lower specific surface area than biochars. Biochars present negligible availability of NO −3 and NH +4 , irrespective of the nitrogen content of the feedstock. For hydrochars, a potential increase in availability of NO −3 , NH +4 , PO 3−4 , and K + with respect to the feedstock is possible. The results from this work can be applied to “engineer” appropriate biochars with respect to soil demands and certification requirements