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The possibility to increase human comfort and reduce the global footprint of buildings is a powerful driving force for introduction of new building technology. Here advanced coating technologies pl ...

Abstract A unique large scale pilot plant of the CellFlux thermal energy storage concept is experimentally investigated. This storage concept consists of a regenerator type thermal energy storage volume, which is coupled to a finned tube heat exchanger by a circulating intermediate working fluid. The system investigated in this work operates at a temperature of 390 °C and uses air as intermediate working fluid which is conveyed by a centrifugal fan. The storage volume has a bed length of over ten meters and is of a novel design, where the air flows in horizontal direction. Since this approach could cause a flow maldistribution, a thorough analysis is of major interest for the accuracy of subsequent numerical simulations. The experiments reveal that the mass flow along the centerline can be up to 20% higher than the mean bulk flow. A significant maldistribution between top and bottom area, however, is not observed. As an alternative to the typically used rock filling, the storage volume is equipped with standard hollow bricks. These bricks are cost effective but do not have a well-defined shape. Thus, the predictability of the pressure drop by correlations found in the literature is unclear. It turns out that the measured pressure drop is evenly distributed in axial flow direction but generally higher than expected from the assumption of pure channel flow. Further experiments are conducted to validate the heat capacity of the bricks and to derive a correlation for the inner heat transfer between bricks and storage walls. Eventually, the aim of the experimental investigation is a general proof of concept as basis for the numerical investigation. Thus, all specifications of the plant and the storage material are provided. The plant is analyzed towards plausibility of heat losses, showing that heat losses can be predicted well within the given uncertainties.

Environment preservation, energy, and the growing economy are becoming strongly interconnected themes requiring new solutions to be exploited. An example of this interconnection is the demand for the development of almost zero-energy buildings, i.e. buildings capable to be almost autonomous from external energy supply or at least not dependent on the energy supply from utilities. The actual conception of a zero energy building is a very complex system formed by several subsystems, with the consequence that costs are very high and reliability relatively low. The aim of this research program is to deepen the possibility to employ the Stirling engine and cooler technology to lower the number of components required in a near zero-energy building, increase the efficiency, and contemporary raise the reliability of the overall system. Stirling cooler could be used to convert mechanical work into heating and cooling effects and produce the temperature difference by the expanding and compressing the working fluid. A similar concept of the Stirling cooler could also be adopted to develop a heat pump. Compared to the traditional vaporcompression refrigeration systems, the Stirling coolers are of higher efficiency and with no components like compressor, expansion valve, evaporator, or condensers. Therefore, they are considered to be clean cooling devices. On the other hand, the Stirling engine is an external combustion engine, which is compatible with a variety of thermal sources, such as solar radiation, waste heat, geothermal energy, combustion, and so on. With the heat input to the hot end of the engine, the Stirling engine could be operated to produce mechanical work/electricity at high thermal efficiency. In principle, the Stirling machines are capable to provide all the forms of energy (heat, cool, and electricity) that form the almost total energy load of a building.

Explaining variation in life history phenology requires us to disentangle environmental-dependent variability from that caused by adaptive change across time and space. Here, we offer thermal time models (models measuring time in temperature units) as tools to understand the spawning dynamics of small pelagic fish, such as Pacific herring Clupea pallasii. We hypothesised that thermal time explains the annual timing of spawning of Pacific herring across space and time. By testing this hypothesis, we identified developmental constants (thermal constants of spawning) that can be used to make spawning time predictions. We examined spatio-temporal changes in Pacific herring spawning time over a 69 yr period (1941-2010) across 6 regions off British Columbia (BC), Canada. We estimated the degree-days (DD, °C-days) from the onset of gonadal maturation to spawning by combining spawning time estimates with distribution-specific temperature estimates. We then fitted models to explore how DD to spawning can be used to explain observed spawning time patterns across space and time and identified temperature-independent sources of variability (e.g. adaptive differences among regions, spawner size). We found that, even though Pacific herring often spawned ∼5 d later with each increasing degree in latitude, the average thermal time in DD to spawning was ∼1700°C-days. We also found that DD to spawning explains linear variation in spawning time across years for some regions of the BC Pacific herring. Thermal time models can aid in predictions of environmental responses and forecasts of life-history phenology in a changing climate.

In bioreactors used for the purification of wastewater, microorganisms are active in biofilms or aggregates. Insight into the factors that determine the structure and function of aggregated biomass is increasing steadily. Besides conventional techniques, modem molecular techniques are used increasingly to get a better understanding of the complex microbial communities in wastewater treatment systems. In recent years, the combined use of these techniques has led to a good insight into the population dynamics of different types of microbes in bioreactors.

This chapter discusses the present scenario and market trend of some important natural plant fibers such as cotton, flax, jute, and hemp. Production, processing, and applications of these fibers are discussed. The factors influencing the sustainability of these natural plant fibers are presented and various lifecycle assessment studies performed on these fibers to evaluate their environmental impacts and sustainability are discussed.

Abstract A numerical and experimental study was conducted, with the purpose of inferring the influence of the CO2 concentration ( x CO 2 ) for different equivalence ratios ( ϕ ) on CH4/CO2/air (biogas) flames chemiluminescence. A thorough analysis on the signals of OH∗, CH∗, C 2 ∗ and CO 2 ∗ was performed. Typical biogas compositions were tested under laminar atmospheric flame conditions, within the unburned equivalence ratio of 0.9 and 1.14 with CO2 concentrations up to 40% in the blend. Experimental measurements of chemiluminescence were done using spectroscopy in the UV–visible region of the spectra. Simulations were performed with the GRI-Mech 3.0 mechanism without accounting for the nitrogen chemistry, extended with a chemiluminescence kinetics of OH∗, CH∗, C 2 ∗ and CO 2 ∗ , in a burner-stabilized frame in CANTERA. Experimental measurements and numerical simulations are compared and generally are in good agreement. It was verified that CO2 dilution leads to a regular decrease in the emission intensities of OH∗, CH∗, C 2 ∗ and CO 2 ∗ . Relations between chemiluminescence intensity ratios and x CO 2 and ϕ were found. It was shown that OH∗/ CO 2 ∗ and C 2 ∗ / CO 2 ∗ have the potential predict x CO 2 in CH4/CO2/air flames. Moreover, it was verified that OH∗/CH∗, OH∗/ C 2 ∗ and CH∗/ C 2 ∗ are well suited to infer ϕ for the blends tested. It was verified that x CO 2 does not cause relevant changes in the chemiluminescence ratios when inferring ϕ .

The high power density, ease of transportation and storage and many years of development of internal combustion engine technologies have put liquid hydrocarbon fuels at a privileged position in our energy mix. Therefore processes that use renewable energy sources to produce liquid hydrocarbon fuels from H2O and CO2 are of crucial importance. Concentrated Solar Power (CSP) can be employed as the only energy source for the renewable production of hydrogen from water either indirectly, e.g. by supplying the electricity for electrolysis, or directly by supplying the necessary heat for thermochemically producing hydrogen. Among the various thermochemical cycles tested so far for CSP-driven hydrogen production via water splitting (WS), those based on redox-pair oxide systems, are directly adaptable to carbon dioxide splitting (CDS) and/or combined CO2/H2O splitting for the production of CO or syngas, respectively. The acknowledgement of this fact has recently revived the interest of the scientific community on such technologies. The current article presents the development, evolution and current status of CSP-aided syngas production via such redox-pair-based thermochemical cycles. At first the various redox oxide material compositions tested for water/carbon dioxide splitting are presented and their redox chemistries are discussed. Then the selection of suitable solar reactors is addressed in conjunction with the boundary conditions imposed by the redox systems as well as the heat demands, technical peculiarities and requirements of the cycle steps. The various solar reactor concepts proposed and employed for such reactions and their current status of development are presented. Finally, topics where further work is needed for commercialization of the technology are identified and discussed.

This paper addresses the current knowledge on climate change impacts on mass movement activity in mountain environments by illustrating characteristic cases of debris flows, rock slope failures and landslides from the French, Italian, and Swiss Alps. It is expected that events are likely to occur less frequently during summer, whereas the anticipated increase of rainfall in spring and fall could likely alter debris-flow activity during the shoulder seasons (March, April, November, and December). The magnitude of debris flows could become larger due to larger amounts of sediment delivered to the channels and as a result of the predicted increase in heavy precipitation events. At the same time, however, debris-flow volumes in high-mountain areas will depend chiefly on the stability and/or movement rates of permafrost bodies, and destabilized rock glaciers could lead to debris flows without historic precedents in the future. The frequency of rock slope failures is likely to increase, as excessively warm air temperatures, glacier shrinkage, as well as permafrost warming and thawing will affect and reduce rock slope stability in the direction that adversely affects rock slope stability. Changes in landslide activity in the French and Western Italian Alps will likely depend on differences in elevation. Above 1500 m asl, the projected decrease in snow season duration in future winters and springs will likely affect the frequency, number and seasonality of landslide reactivations. In Piemonte, for instance, 21st century landslides have been demonstrated to occur more frequently in early spring and to be triggered by moderate rainfalls, but also to occur in smaller numbers. On the contrary, and in line with recent observations, events in autumn, characterized by a large spatial density of landslide occurrences might become more scarce in the Piemonte region.

Starting from an interpretation of “sustainable mobility”, this study describes a possible taxonomy of the modalities of urban travels related to sustainability and it suggests an inclusive approach to implement urban policies for “soft mobility” inside the urban contexts. These policies aim at improving the levels of urban liveability, reducing the polluting emissions and promoting the recovery of a sober moral behaviour in acting and reacting inside the city. The underway photovoltaic bikesharing project “Bene Bike” in Benevento shows how the bike station plays an innovative role. It represents a multifunctional element able of managing material and immaterial “flows of urban travels” (people, energy, information).