Assessment of Cumulative Energy Needs for Chosen Technologies of Cattle Feeding in Barns with Conventional (CFS) and Automated Feeding Systems (AFS)

The increasing popularity of automated systems and the increased market share of producers of robotic feeding equipment for cows causes the need for a deeper study of energy demand in such technologies. This article provides an analysis of the inputs of energy accumulated in conventional (CFS) and automated feeding systems (AFS) for cattle. The aim of this is to determine the impact of robotic technologies for the preparation and feeding of fodder on the cumulative energy inputs. The aim of this paper is to investigate the effect of machinery and the equipment applied to the cumulative energy intensity in cattle farming facilities. The cumulative energy consumption for four technologies of automated cattle feeding (AFS) was tested and compared to the energy consumption for six technologies with a conventional feeding system (CFS). The research involved nine cow barn facilities for dairy cows and one for beef cattle. An evaluation has been made for cattle farming structures (milk and meat production) with various mixing and feeding systems for feeds of various concentrations, and keeping system (tied system and free-stall). The cow barns differed in feed mixing, feeding machinery, and equipment. Measurements of live labor inputs and the consumption of electric and mechanical energy carriers were carried out, and the mass of various types of machines and devices with software was taken into account, which became the basis for calculating cumulative energy consumption for individual technologies. The obtained average of electric and mechanical energy inputs for robotic technologies of feeding fodder (AFS) was 0.60025 kWh∙day−1∙LU−1(where LU means Large Animal Unit 500 kg), and it was 39.3% lower than for conventional technologies (CFS) where it was 0.989052 kWh∙day−1∙LU−1. However, taking into account all components of cumulative energy consumption, the average for the group of robotic technologies (AFS) was higher by 35.18% than for conventional technologies (CFS).

Energy at Origins: Favorable Thermodynamics of Biosynthetic Reactions in the Last Universal Common Ancestor (LUCA)

Though all theories for the origin of life require a source of energy to promote primordial chemical reactions, the nature of energy that drove the emergence of metabolism at origins is still debated. We reasoned that evidence for the nature of energy at origins should be preserved in the biochemical reactions of life itself, whereby changes in free energy, ΔG, which determine whether a reaction can go forward or not, should help specify the source. By calculating values of ΔG across the conserved and universal core of 402 individual reactions that synthesize amino acids, nucleotides and cofactors from H2, CO2, NH3, H2S and phosphate in modern cells, we find that 95–97% of these reactions are exergonic (ΔG ≤ 0 kJ⋅mol−1) at pH 7-10 and 80-100°C under nonequilibrium conditions with H2 replacing biochemical reductants. While 23% of the core’s reactions involve ATP hydrolysis, 77% are ATP-independent, thermodynamically driven by ΔG of reactions involving carbon bonds. We identified 174 reactions that are exergonic by –20 to –300 kJ⋅mol−1 at pH 9 and 80°C and that fall into ten reaction types: six pterin dependent alkyl or acyl transfers, ten S-adenosylmethionine dependent alkyl transfers, four acyl phosphate hydrolyses, 14 thioester hydrolyses, 30 decarboxylations, 35 ring closure reactions, 31 aromatic ring formations, and 44 carbon reductions by reduced nicotinamide, flavins, ferredoxin, or formate. The 402 reactions of the biosynthetic core trace to the last universal common ancestor (LUCA), and reveal that synthesis of LUCA’s chemical constituents required no external energy inputs such as electric discharge, UV-light or phosphide minerals. The biosynthetic reactions of LUCA uncover a natural thermodynamic tendency of metabolism to unfold from energy released by reactions of H2, CO2, NH3, H2S, and phosphate.

The effect of tidal force and topography on horizontal convection

We present a numerical study on how tidal force and topography influence flow dynamics, transport and mixing in horizontal convection. Our results show that local energy dissipation near topography will be enhanced when the tide is sufficiently strong. Such enhancement is related to the height of the topography and increases as the tidal frequency $\omega$ decreases. The global dissipation is found to be less sensitive to the changes in $\omega$ when the latter becomes small and asymptotically approaches a constant value. We interpret the behaviour of the dissipation as a result of the competition among the dominant forces in the system. According to which mechanism prevails, the flow state of the system can be divided into three regimes, which are the buoyancy-, tide- and drag-control regimes. We show that the mixing efficiency $\eta$ for different tidal energy and topography height can be well described by a universal function $\eta \approx \eta _{HC}/(1+\mathcal {R})$ , where $\eta _{HC}$ is the mixing efficiency in the absence of tide and $\mathcal {R}$ is the ratio between tidal and available potential energy inputs. With this, one can also determine the dominant mechanism at a certain ocean region. We further derive a power law relationship connecting the mixing coefficient and the tidal Reynolds number.

The Deep Rocky Biosphere: New Geomicrobiological Insights and Prospects

Rocks that react with liquid water are widespread but spatiotemporally limited throughout the solar system, except for Earth. Rock-forming minerals with high iron content and accessory minerals with high amounts of radioactive elements are essential to support rock-hosted microbial life by supplying organics, molecular hydrogen, and/or oxidants. Recent technological advances have broadened our understanding of the rocky biosphere, where microbial inhabitation appears to be difficult without nutrient and energy inputs from minerals. In particular, microbial proliferation in igneous rock basements has been revealed using innovative geomicrobiological techniques. These recent findings have dramatically changed our perspective on the nature and the extent of microbial life in the rocky biosphere, microbial interactions with minerals, and the influence of external factors on habitability. This study aimed to gather information from scientific and/or technological innovations, such as omics-based and single-cell level characterizations, targeting deep rocky habitats of organisms with minimal dependence on photosynthesis. By synthesizing pieces of rock-hosted life, we can explore the evo-phylogeny and ecophysiology of microbial life on Earth and the life’s potential on other planetary bodies.

Electrochemical Ammonia: Power to Ammonia Ratio and Balance of Plant Requirements for Two Different Electrolysis Approaches

Electrochemical ammonia generation allows direct, low pressure synthesis of ammonia as an alternative to the established Haber-Bosch process. The increasing need to drive industry with renewable electricity central to decarbonisation and electrochemical ammonia synthesis offers a possible efficient and low emission route for this increasingly important chemical. It also provides a potential route for more distributed and small-scale ammonia synthesis with a reduced production footprint. Electrochemical ammonia synthesis is still early stage but has seen recent acceleration in fundamental understanding. In this work, two different ammonia electrolysis systems are considered. Balance of plant (BOP) requirements are presented and modelled to compare performance and determine trade-offs. The first option (water fed cell) uses direct ammonia synthesis from water and air. The second (hydrogen-fed cell), involves a two-step electrolysis approach firstly producing hydrogen followed by electrochemical ammonia generation. Results indicate that the water fed approach shows the most promise in achieving low energy demand for direct electrochemical ammonia generation. Breaking the reaction into two steps for the hydrogen fed approach introduces a source of inefficiency which is not overcome by reduced BOP energy demands, and will only be an attractive pathway for reactors which promise both high efficiency and increased ammonia formation rate compared to water fed cells. The most optimised scenario investigated here with 90% faradaic efficiency (FE) and 1.5 V cell potential (75% nitrogen utilisation) gives a power to ammonia value of 15 kWh/kg NH3 for a water fed cell. For the best hydrogen fed arrangement, the requirement is 19 kWh/kg NH3. This is achieved with 0.5 V cell potential and 75% utilisation of both hydrogen and nitrogen (90% FE). Modelling demonstrated that balance of plant requirements for electrochemical ammonia are significant. Electrochemical energy inputs dominate energy requirements at low FE, however in cases of high FE the BOP accounts for approximately 50% of the total energy demand, mostly from ammonia separation requirements. In the hydrogen fed cell arrangement, it was also demonstrated that recycle of unconverted hydrogen is essential for efficient operation, even in the case where this increases BOP energy inputs.

Thermodynamic Constraints on Electromicrobial Protein Production

Global consumption of protein is projected to double by the middle of the 21st century. However, protein production is one of the most energy intensive and environmentally damaging parts of the food supply system today. Electromicrobial production technologies that combine renewable electricity and CO2-fixing microbial metabolism could dramatically increase the energy efficiency of commodity chemical production. Here we present a molecular-scale model that sets an upper limit on the performance of any organism performing electromicrobial protein production. We show that engineered microbes that fix CO2 and N2 using reducing equivalents produced by H2-oxidation or extracellular electron uptake could produce amino acids with energy inputs as low as 64 MJ kg-1. This work provides a roadmap for development of engineered microbes that could significantly expand access to proteins produced with a low environmental footprint.

The Hydrological System and Climate of Brewster Glacier, Tititea Mt Aspiring National Park, Southern Alps, Aotearoa New Zealand, in the Context of Climate Change.

<p>Temporal and spatial variability of stream discharge is directly related to variation in local climate, and this in turn is related to both regional and global atmospheric circulation and climate change. The relationship is complicated in glacierised catchments. This study aims to identify relationships between discharge from Brewster Glacier proglacial stream and both local atmospheric variables and national atmospheric circulation patterns. An attempt is made to quantify these relationships using statistical models and tests in order that prediction of discharge with climate change could be made using local weather forecasts and national circulation indices. The nature of the subglacial drainage system is also investigated with particular focus on its structural evolution from summer to autumn. It is found that shortwave radiation, wind speed and relative humidity are consistently the most important variables in prediction of discharge and that wind speed is most important during summer while air temperature is most important in autumn. It is concluded that the importance of precipitation is greater than indicated by the results which were influenced by covariance in the records. A multiple regression model for summer discharge predicts up to 85% of variation in the proglacial stream hydrograph and for autumn 60%. Low overall energy inputs during autumn result in lesser sensitivity of discharge to variation in environmental conditions. It is concluded that the subglacial drainage system is highly arborescent over both summer and autumn and that little, if any, evolution occurs through these seasons. A qualitative relationship is established between discharge production at Brewster Glacier proglacial stream and national atmospheric circulation indices; highest average discharge occurs during northwesterly cyclonic conditions, when the turbulent heat fluxes and precipitation dominate discharge production, and lowest during southeasterly anticyclones when total energy inputs are low. The multiple regression models are used to estimate changes in discharge over the next 20 years given predicted changes in air temperature and precipitation, and it is found that the models lack the sensitivity required for accurate predictions.</p>

The Hydrological System and Climate of Brewster Glacier, Tititea Mt Aspiring National Park, Southern Alps, Aotearoa New Zealand, in the Context of Climate Change.

<p>Temporal and spatial variability of stream discharge is directly related to variation in local climate, and this in turn is related to both regional and global atmospheric circulation and climate change. The relationship is complicated in glacierised catchments. This study aims to identify relationships between discharge from Brewster Glacier proglacial stream and both local atmospheric variables and national atmospheric circulation patterns. An attempt is made to quantify these relationships using statistical models and tests in order that prediction of discharge with climate change could be made using local weather forecasts and national circulation indices. The nature of the subglacial drainage system is also investigated with particular focus on its structural evolution from summer to autumn. It is found that shortwave radiation, wind speed and relative humidity are consistently the most important variables in prediction of discharge and that wind speed is most important during summer while air temperature is most important in autumn. It is concluded that the importance of precipitation is greater than indicated by the results which were influenced by covariance in the records. A multiple regression model for summer discharge predicts up to 85% of variation in the proglacial stream hydrograph and for autumn 60%. Low overall energy inputs during autumn result in lesser sensitivity of discharge to variation in environmental conditions. It is concluded that the subglacial drainage system is highly arborescent over both summer and autumn and that little, if any, evolution occurs through these seasons. A qualitative relationship is established between discharge production at Brewster Glacier proglacial stream and national atmospheric circulation indices; highest average discharge occurs during northwesterly cyclonic conditions, when the turbulent heat fluxes and precipitation dominate discharge production, and lowest during southeasterly anticyclones when total energy inputs are low. The multiple regression models are used to estimate changes in discharge over the next 20 years given predicted changes in air temperature and precipitation, and it is found that the models lack the sensitivity required for accurate predictions.</p>