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This dataset, in the context of the MultiPACK Project, describes the development of a CO2 air/water reversible heat pump, specifically investigating the domestic hot water (DHW) production operating mode. A dynamic model of the heat pump is developed with the software Simcenter Amesim. After validation against experimental data, the numerical model is utilized to predict the performance of the heat pump to varying hot water demand, evaporator air inlet conditions and high-pressure value, leading to the discussion of the optimal control strategy. A paper, based on this dataset, "Experimental and numerical investigation of a transcritical CO2 air/water reversible heat pump: analysis of domestic hot water production (14th Gustav Lorentzen Conference, Kyoto, Japan, 6th- 9th December 2020, DOI:10.18462/iir.gl.2020.1160).

Comprehensive and reliable information on anthropogenic sources of greenhouse gas emissions is required to track progress towards keeping warming well below 2°C as agreed upon in the Paris Agreement. Here we provide a dataset on anthropogenic GHG emissions 1970-2019 with a broad country and sector coverage. We build the dataset from recent releases from the “Emissions Database for Global Atmospheric Research” (EDGAR) for CO2 emissions from fossil fuel combustion and industry (FFI), CH4 emissions, N2O emissions, and fluorinated gases and use a well-established fast-track method to extend this dataset from 2018 to 2019. We complement this with information on net CO2 emissions from land use, land-use change and forestry (LULUCF) from three available bookkeeping models.

In this dataset, the field data from an integrated CO2 refrigeration system installed in a supermarket located north of the capital of Lisbon was shared. The scheme of the refrigerating system is provided in Figure 1-2, while the installed capacities and main components characteristics are listed in Table 1 and Table 2, respectively.The system can meet AC demand by direct evaporation in the air handling units (AHUs) units. Due to the summer season and warm ambient temperatures, AC is applied to meet the temperature set-point inside the shop (Figure 2). Moreover, compressor racks and AHU units are shown only with a single symbol. The system consists of the LT compressor rack (three semi-hermetic compressors), the MT compressor rack (four semi-hermetic compressors), and the parallel compressor (PC) rack (four semi-hermetic compressors) for AC; a gas cooler (GC); MEs; liquid receiver, MT suction line accumulator; LT and MT evaporators, expansion valves (EVs), oil recovery system, and two rooftop AHUs. For each compressor rack, one compressor is equipped with an inverter to allow smoother capacity modulation. The PCs are organized in such a way that they can manage different suction pressures according to heat pump functionality and/or PC. The ME blocks were sized for vapor pre-compression (HPE) according to the climate profile of the region and liquid return (LE) in the case of liquid leaving the MT evaporators. The AHU comprises two identical rooftop units. These units deliver the entire heating and cooling capacity of the supermarket. CO2 is directly applied inside the heating and cooling coils of the AHUs. SH demand can be covered seamlessly by means of a 3-way valve allowing high pressure CO2 gas supply to the heating coils in the AHU. An increasing high pressure and separate heat pump functionality can be utilized to cover high heating demands. In summertime, the AHU’s cooling coils can be operated in two different ways: the first alternative is the DX downstream of the GC, i.e., the refrigerant expands from the high-pressure side directly into the coils where it is evaporated and enters the liquid receiver. The second alternative is using a low-pressure lift high entrainment ratio ejector (AC ejector). The AC ejector sucks the whole vapor of the AC evaporators to compress it to the receiver pressure level. The first alternative was in operation during the time period analyzed in this study; thus, the effect of AC ejectors will not be mentioned in the following sections. High-pressure lift and liquid ejectors are applied to return both vapor and liquid from the suction line accumulator to the liquid receiver.

Model projections show that production of high-value products from microalgae could be profitable nowadays and commodities will become profitable within 10 years.

Abstract. Reliable quantification of the sources and sinks of greenhouse gases, together with trends and uncertainties, is essential to monitoring the progress in mitigating anthropogenic emissions under the Paris Agreement. This study provides a consolidated synthesis of CH4 and N2O emissions with consistently derived state-of-the-art bottom-up (BU) and top-down (TD) data sources for the European Union and UK (EU27+UK). We integrate recent emission inventory data, ecosystem process-based model results, and inverse modelling estimates over the period 1990–2018. BU and TD products are compared with European National GHG Inventories (NGHGI) reported to the UN climate convention secretariat UNFCCC in 2019. For uncertainties, we used for NGHGI the standard deviation obtained by varying parameters of inventory calculations, reported by the Member States following the IPCC guidelines recommendations. For atmospheric inversion models (TD) or other inventory datasets (BU), we defined uncertainties from the spread between different model estimates or model specific uncertainties when reported. In comparing NGHGI with other approaches, a key source of bias is the activities included, e.g. anthropogenic versus anthropogenic plus natural fluxes. In inversions, the separation between anthropogenic and natural emissions is sensitive to the geospatial prior distribution of emissions. Over the 2011–2015 period, which is the common denominator of data availability between all sources, the anthropogenic BU approaches are directly comparable, reporting mean emissions of 20.8 Tg CH4 yr−1 (EDGAR v5.0) and 19.0 Tg CH4 yr−1 (GAINS), consistent with the NGHGI estimates of 18.9 ± 1.7 Tg CH4 yr−1. TD total inversions estimates give higher emission estimates, as they also include natural emissions. Over the same period regional TD inversions with higher resolution atmospheric transport models give a mean emission of 28.8 Tg CH4 yr−1. Coarser resolution global TD inversions are consistent with regional TD inversions, for global inversions with GOSAT satellite data (23.3 Tg CH4yr−1) and surface network (24.4 Tg CH4 yr−1). The magnitude of natural peatland emissions from the JSBACH-HIMMELI model, natural rivers and lakes emissions and geological sources together account for the gap between NGHGI and inversions and account for 5.2 Tg CH4 yr−1. For N2O emissions, over the 2011–2015 period, both BU approaches (EDGAR v5.0 and GAINS) give a mean value of anthropogenic emissions of 0.8 and 0.9 Tg N2O yr−1 respectively, agreeing with the NGHGI data (0.9 ± 0.6 Tg N2O yr−1). Over the same period, the average of the three total TD global and regional inversions was 1.3 ± 0.4 and 1.3 ± 0.1 Tg N2O yr−1 respectively, compared to 0.9 Tg N2O yr−1 from the BU data. The TU and BU comparison method defined in this study can be operationalized for future yearly updates for the calculation of CH4 and N2O budgets both at EU+UK scale and at national scale. The referenced datasets related to figures are visualized at https://doi.org/10.5281/zenodo.4288969 (Petrescu et al., 2020).

Abstract A requirement for the development of a viable biomass conversion technology for clean energy production is the efficient cleaning of the gas fraction. The aim of this work was to use fly ash (AF) to develop cheap and efficient catalysts in removing tar. FA was separated in two fraction, oxide fly ash (OFA) and unburned carbon (UCFA) and both were used for catalysts preparing. The toluene was used as a tar model and a fixed-bed reactor for testing. The calcined oxide fly ash (COFA) showed a steady decrease in catalytic activity, the removal efficiency was reduced by 13.52% after 3 h. Reduced catalyst (RCOFA) and activated and reduced catalyst (AROFA) showed a higher activity than COFA catalyst and were able to maintain their performance. The RCOFA catalytic activity decreased suddenly when the steam was present, and tar removal efficiency descended to 57.32% after only 3 h and to 49.03% after 5hrs, respectively. Results showed that the catalysts obtaining by mixing RCOFA/AROFA with UCFA led to high effective toluene conversion in a reforming environment, over 90% and their catalytic activity remained constant after 12 h, because the unburned carbon presence kept the iron in its reduced form, much more catalytically active.

The following Diploma thesis presents the development of a model for predicting the consumption of electrical and thermal energy in residential buildings. A model which allows the calculation of energy usage on the basis of the surface of the building and additional influencing factors has been developed on the basis of the data on the energy usage in residential buildings. It was made upon the basis of the analysis of data acquired in the area of Dolenjska and is designed to predict the usage of electrical and thermal energy in the apartments, independent houses, and houses with associated farm buildings on the basis of the input data. Each type of the residential building has been modelled separately for the usage of electrical and thermal energy. I managed to develop the model for predicting the usage of electrical and thermal energy which – at 40 cases of test data – successfully predicted the energy consumption at the accuracy of ±35 %, its average deviation from the actual usage being 12 %. V diplomskem delu je predstavljen razvoj modela za napoved rabe električne in toplotne energije v stanovanjskih objektih. Na podlagi podatkov o rabi energije v stanovanjskih objektih je bil razvit model, ki omogoča izračun rabe na podlagi površine objekta in dodatnih vplivnih faktorjev. Model je bil sestavljen na podlagi analize podatkov, pridobljenih na območju dolenjske regije. Narejen je tako, da na podlagi vhodnih podatkov napove rabo električne in toplotne energije v stanovanjih, samostojnih hišah in hišah s kmetijskim poslopjem. Vsak tip stanovanjskega objekta sem modeliral ločeno tako za rabo električne kot tudi toplotne energije. Uspelo mi je razviti model za napoved rabe električne in toplotne energije, ki je pri 40-ih testnih podatkih napovedal rabo energije ±35 % točno, njegovo povprečno odstopanje od dejanske rabe pa je 12 %.

The torrefaction process upgrades biomass characteristics and produces solid biofuels that are coal-like in their properties. Kinetics analysis is important for the determination of the appropriate torrefaction condition to obtain the best utilization possible. In this study, the kinetics (Friedman (FR) and Kissinger–Akahira–Sunose (KAS) isoconversional methods) of two final products of lignocellulosic feedstocks, miscanthus (Miscanthus x giganteus) and hops waste (Humulus Lupulus), were studied under different heating rates (10, 15, and 20 °C/min) using thermogravimetry (TGA) under air atmosphere as the main method to investigate. The results of proximate and ultimate analysis showed an increase in HHV values, carbon content, and fixed carbon content, followed by a decrease in the VM and O/C ratios for both torrefied biomasses, respectively. FTIR spectra confirmed the chemical changes during the torrefaction process, and they corresponded to the TGA results. The average Eα for torrefied miscanthus increased with the conversion degree for both models (25–254 kJ/mol for FR and 47–239 kJ/mol for the KAS model). The same trend was noticed for the torrefied hops waste samples; the values were within the range of 14–224 kJ/mol and 60–221 kJ/mol for the FR and KAS models, respectively. Overall, the Ea values for the torrefied biomass were much higher than for raw biomass, which was due to the different compositions of the torrefied material. Therefore, it can be concluded that both torrefied products can be used as a potential biofuel source.

The dataset presents, the estimation of the Multi-ejector performance in a supermarket, based on the compressor mass flow rates from a trained data-driven method, (refer to https://doi.org/10.18710/HS8QAH) and the comparison with the existing performance function based on operational conditions. The pilot installation used the dataset is in the frame of MultiPack, an EU funded project. The Multipack is an integrated R744 parallel compression system with expansion work recovery through Multi Ejector SolutionTM, providing: refrigeration, space heating and cooling, and hot water production as shown in Figure 1. The space cooling and heating are by two direct CO2 rooftop air handling units. Three compression groups were installed in the pilot. Three compressors for medium temperature level (MT comp), three compressors at Low-Temperature level (LT comp), and four units are dedicated for Air-Conditioning (AC comp) total installed electrical power for compressors and fans is 177 kW (Excluding air handling fans). A paper, based on this dataset, "Performance of integrated R744-packs Part 2 - Ejectors performance, a comparison of onsite measurements and model predictions" was published at a conference (Compressors Conferences).

Abstract A consideration of second-law analysis has been extended from the heat exchanger network to an overall energy balance of a chemical process. This enables the simultaneous integration of all kinds of energy-active apparatus (e.g. reactors, compressors, turbines, boilers, refrigerators, coolers, heaters) and hot feeds or effluents into a process flowsheet. The apparatus and the feeds or effluents together represent a utility exchanger network (UEN), process streams are utilized by several types of energy (utilities) that are of a chemical, mechanical, electrical, transmissible, radiative, or heat flow origin. Inherent and avoidable utilities are distinguished. An action of each utility on the enthalpy change of the process stream is represented in a temperature—enthalpy diagram by the corresponding utility stream. Hot utility streams are composed into a hot composite curve (UCC). It sums up the energy inflows and energy production of the system, called energy donors. On the other hand, cold utility streams are composed into a cold UCC that comprises energy outflows and energy consumption (energy acceptors). Process streams are excluded in this step. By matching both UCCs the method enables the direct targeting of an economical overall utility system through is structural and parametric modifications. Targeting is facilitated by using general rules for appropriate integration of energy donors and energy acceptors relative to the utility pinch temperature. At the same time, the improved energy system changes the dynamical performances; the control configuration must be adopted to the new structure of the total system. The method is based on a detailed thermodynamic analysis of process units and is followed by an optimal thermodynamic synthesis of the total system. The final detailed parametrical optimization is similar to the classic pinch analysis. It deals with process streams and brings additional savings. The whole procedure has been tested on an existing chemical process and its effectiveness has been proved.