Case Studies In Austria Research Articles

Quantifying the stability of refugee populations: a case study in Austria

The global surge in displacement, with nearly 110 million people uprooted due to violence, underscores the pressing need to comprehend the challenges faced by refugees. Population growth, environmental crises, and political instability contribute to this crisis, projecting an escalating trend in the decades ahead. While hosting countries strive to address concerns related to labour markets, state provisions, and cultural integration, understanding the well-being of refugees upon entry needs to be more adequately explored. This study focuses on refugee stability and integration, employing Austria as a case study. Stability is assessed through residential movement, where more frequent moves indicate instability. Utilising comprehensive administrative data spanning November 2022 to November 2023, we examine residence movements as a proxy for stability. Our findings reveal a stark contrast in the stability of refugees compared to other migrant groups. Analysing movement profiles, we establish that refugees exhibit significantly higher rates of residential mobility than their counterparts, especially among male refugees. This imbalance persists even when comparing refugees to migrants from top refugee-sending countries without official refugee status. This study contributes valuable insights into the intricate dynamics of refugee stability, shedding light on the enduring challenges faced by this population. By examining movement patterns as a key indicator, we provide a nuanced understanding of the residential experiences of refugees, that can inform targeted policies and interventions for enhanced refugee well-being and integration.

A methodology for the determination of future Carbon Management Strategies: A case study of Austria

The achievement of global climate targets outlined in the Paris Agreement represents a critical challenge in the coming decades. Certain industry sectors cannot completely avoid all emissions from their processes. In this context, the term unavoidable or Hard-to-abate emissions is used. Carbon Capture and Utilization (CCU) and Carbon Capture and Storage (CCS) are recognized as essential components for addressing those emissions to achieve Net Zero Emissions. To identify effective Carbon Management Strategies, balancing future CO2 sources and possible sinks for achieving long-term climate targets is essential. Especially in Austria hardly any comprehensive studies have been carried out. This work presents a comprehensive analysis of Austria’s CO2 point sources as well as their projected development until 2050 based on technology-based scenarios. Geological CO2 storage in Austria is primarily feasible in former hydrocarbon reservoirs and saline aquifers. Future demands for CO2 as CCU feedstock will arise in the chemical industry. By 2050, industry will emit approximately 4 Mt of unavoidable CO2 annually. These emissions must be stored in the long term and correspond to the minimum demand for CCS. Fugitive emissions from agriculture, for example, cannot be captured. Thus, they are not subject of CCU/S measures. Negative emissions are therefore necessary to achieve the climate targets. These negative emissions and the possible use of CO2 as feedstock are covered by biogenic CO2.

Cost-Driven Assessment of Technologies’ Potential to Reach Climate Neutrality in Energy-Intensive Industries

Efforts towards climate neutrality in Europe must prioritise manufacturing industries, particularly the energy-intensive industry (EII) subsectors. This work proposes a novel approach to assessing transformation options for EII subsectors. At the center of this approach we position a potential analysis of technologies’ impact on subsector decarbonisation—an approach only known so far from the investigation of renewable energy potentials. These so-called technical climate neutrality potentials, supplemented by a set of indicators taking into account energy consumption, capital and operational expenditures, and GHG taxation programs per technology and subsector, enable cross-sector comparisons. The indicators allow the reader to compare the impact on GHG emission mitigation, energy demand, and cost for every considered technology. At the same time, we keep an open mind regarding combinations of technological solutions in the overall energy system. This ensures that the technology pathways with the greatest climate neutrality potential are easily identified. These focal points can subsequently serve in, e.g., narrative-driven scenario analyses to define comprehensive guides for action for policymakers. A case study of Austria for the proposed potential analysis demonstrates that bio-CH4 and electrolysis-derived H2 are the most economical green gases, but GHG certificate costs will be necessary for cost-competitiveness in high-temperature applications. Electrification offers advantages over conventional technologies and CO2-neutral gas alternatives in low-to-mid temperature ranges. Under the given assumptions, including GHG emission certificate costs of 250 EUR/t CO2, alternative technologies in the identified climate neutrality pathways can operate at total annual costs comparable to conventional fossil-based equivalents.

Financing Green Infrastructure in Schools: A Case Study in Austria

Despite the positive effects of green infrastructure on people and the environment, it is still rarely integrated in public facilities such as schools. The main reason for this is a lack of knowledge about financing options. To fill this gap, the research project MehrGrüneSchulen (Engl.: More Green Schools) develops financing scenarios for green infrastructure in Austrian schools. This case study describes these developed scenarios, which use the principles of crowdsourcing and crowdfunding as well as the newly named principle of chain building. The idea of chain building is to motivate schools that have already successfully financed and built a low-cost greening system to present this process to another school in such a way that they are able to do the same themselves and eventually explain the process to a further school to continue this chain reaction. For the proposed funding scenarios to be effective, there is a need for innovation in education, with a focus on inter-school participation and networking. For this reason, the possible synergies of an online networking platform are discussed, which would help to connect schools and thus further improve the impact of the proposed fundraising processes.

Augmented Reality for Building Authorities: A Use Case Study in Austria

The widespread usage of BIM and technological advances in augmented reality (AR) paves the way for Construction 4.0. This digital transformation has reached the construction industry and requires consideration of all life cycle phases. The approval phase has been little researched to date. In Vienna, the analogous process takes up to 18 months. This long duration inhibits progress in the building industry. One reason for this is objections from parties who are nonexperts and have difficulty understanding the project solely from its 2D plans. Therefore, the City of Vienna wants to redesign the building authority processes through the use of BIM and AR in the BRISE-Vienna research project. This article examines possible applications for public authorities. AR can be utilised at the interface between authorities and stakeholders and is intended to accelerate processes through better communication. For the City of Vienna, 12 AR use cases were developed from process analyses and expert interviews. In addition to the conception of the AR use cases for public authorities, a study was carried out regarding their benefits and feasibility. The use cases have the potential to increase the understanding of the project for experts and nonexperts. The best-rated AR use cases (plan checking and hearing during the permission process) will be further developed in the research project. The AR use cases should help to significantly accelerate processes in Vienna and, thus, serve as a basis for other cities and countries.

Implementation of Economic Instruments in the EU Forest-Based Sector: Case Study in Austria and the Czech Republic

Economic instruments are political tools created to promote environmental stewardship by influencing consumption and production patterns, fostering technological innovation, and improving the environment; however, if current failures in their formulation or implementation persist, they can negatively impact the environment and society. This research aims to analyze the strengths, weaknesses, opportunities, and threats (SWOT) of economic instruments by extracting these aspects from the forest policy documents of the EU, Austria, and the Czech Republic using the qualitative content analysis method. It has been found that the EU channels its resources from economic instruments through various financing programs that make distribution more effective and align with the environmental objectives of the EU. Additionally, the SWOT analysis indicates that the economic instruments applied in the EU present significant differences in the application and management of forests and the performance of the financial instruments according to the national strategies and action plans used. These identified challenges, limitations, and improvement areas allow for generating suggestions that policymakers can apply concerning the use, implementation, dissemination, and access processes of financing mechanisms for sustainable forest management in the European Union.

Flexibility potential of aggregated electric vehicle fleets to reduce transmission congestions and redispatch needs: A case study in Austria

Redispatch measures are a key instrument of the Central European electricity market design to prevent congestion of several transmission lines after the market clearing. In addition to generation rescheduling, demand-side flexibility can reduce this redispatch need. This paper mainly aims to analyse the flexibility demand application of electric vehicle fleets in the redispatch market. The developed European electricity market model minimises dispatch- and subsequently redispatch costs whilst using electric vehicle fleets as flexible demand. A novel modelling approach allows the integration of this flexibility into large-scale linear programming models without losing their essential parameters. This case study is examined in Austria with a remarkably high share of electricity from renewable energy sources and different market penetrations of electromobility. Results show that integrating this system as a redispatch measure leads to a reduced curtailment of renewable energies (up to 25%), whilst less additional thermal power plant usage is needed. Furthermore, redispatch cost and the associated CO2 emissions are reduced by 3.3% to 13.9%. By contrast, using this flexibility as a market-based charging strategy raises CO2 emissions and redispatch costs drastically by 186% if 2 million electric vehicles are considered. Especially with the high electrification rate of the transport sector, the provided flexibility potential significantly impacts the electricity market. Further efforts could address the influence of demand-side flexibility not only on redispatch within one control area but also on cross-border redispatch and counter-trading.

Social innovations for supporting regenerative lifestyles: exploration of three pioneering co-housing projects in Austria.

“Limiting global temperature increase needs demand-side actions and lifestyle changes”, stated the IPCC in their Special Report on Global Warming of 1.5. Social innovation in the form of alternative models for spatial production and ownership can support such regenerative lifestyles and emission reductions in the emissions-heavy building sector. However, today’s real estate market hardly supports the development and realization of alternative housing models. In response, practice shows that innovative models of housing are often driven by the initiative of the (future) inhabitants. In this study, we investigate and analyze different models of social innovation in housing based on three recently completed building case studies in Austria. The case studies are situated in a broad range of spatial contexts: re-activating the countryside, vitalizing a newly developed neighborhood, or bringing new life to abandoned, existing buildings. They are showcasing strategies such as: innovative models of (co-)financing and (co-)ownership to provide affordable housing; the shared use of spaces, functions and resources for reducing environmental footprints. We provide insights as to how alternative housing projects are being established successfully, what models groups are exploring for governance, financing and ownership, and which other social innovation practices may support or enable the implementation of regenerative lifestyles.

On the economics of a hydrogen bus fleet powered by a wind park – A case study for Austria

This paper investigates the economics of a fuel cell bus fleet powered by hydrogen produced from electricity generated by a wind park in Austria. The main research question is to simultaneously identify the most economical hydrogen generation business model for the electric utility owning wind power plants and to evaluate the economics of operating a fuel cell bus fleet, with the core objective to minimize the total costs of the overall fuel supply (hydrogen production) and use (bus and operation) system. For that, three possible operation modes of the electrolyzer have been identified and the resulting hydrogen production costs calculated. Furthermore, an in-depth economic analysis of the fuel cell buses as well as the electrolyzer technology has been conducted. Results show that investment costs are the largest cost factor for both technologies. Thus, continuous hydrogen production with the smallest possible electrolyzer is the economically most favorable option. In such an operation mode (power grid), the costs of production per kg/H2 were the lowest. However, this means that the electrolyzer cannot be solely operated with electricity from the wind park, but is also dependent on the electricity mix from the grid. For fuel cell buses, the future cost development will depend very much on the respective policies and funding programs for the market uptake, as to date, the total cost of use for the fuel cell bus is more than two times higher than the diesel bus. The major final conclusion of this paper is that to make fuel cell electric busses competitive in the next years today severe policy interferences, such as subsidies for these busses as well as electrolyzers and bans for fossil energy, along with investments in the setup of a hydrogen infrastructure, are necessary.

EIA Effectiveness in Sensitive Alpine Areas: A Comparison of Winter Tourism Infrastructure Development in Germany and Austria

The paper analyses the effectiveness of the environmental impact assessment (EIA) in sensitive alpine environments by studying processes and selected case studies in Austria and Germany. The framework used to evaluate the respective effectiveness is based on four dimensions of effectiveness: procedural, substantive, transactive and normative. The study is based on semi-structured interviews, workshops with key stakeholders and textual analysis of EIA documents, as well as the analysis of legal documents. The findings reveal significant differences between the two countries leading to lower transactive and lower normative effectiveness in Austria. The framework demonstrates its high suitability for analysing EIA effectiveness and for developing recommendations. The outcomes also underline the significant influence of the project type.

Systematic data-driven exploration of Austrian wastewater and sludge treatment - implications for phosphorus governance, costs and environment

Within the new policy framework shaped by the EU Green Deal and the Circular Economy Action Plans, the field of wastewater and sludge treatment in Europe is subject to high expectations and new challenges related to mitigation of greenhouse gas emissions, micropollutant removal and resource recovery. With respect to phosphorus recovery, several technologies and processes have been thoroughly investigated. Nevertheless, a systemic and detailed understanding of the existing infrastructure and of the related environmental and economic implications is missing. Such basis is essential to avoid unwanted consequences in designing new strategies, given the long lifespan of any infrastructural change. This study couples a newly collected and highly detailed database for all wastewater treatment plants in Austria bigger than 2000 population equivalent with a combination of analyses, namely Substance Flow Analysis with focus on nutrient and metal distribution in different environmental and anthropogenic compartments, Energy Flow Analysis, Life Cycle Assessment and cost estimation. The case study of Austria is of special interest, given its highly autonomous administration in federal states and its contrasting traits, ranging from flat metropolitan areas like Vienna to low-populated alpine areas. The significant impact of electricity demand of wastewater treatment on the overall Cumulative Energy Demand (CED) shows the importance of optimization measures. Further, the current system of wastewater and sludge disposal have a low efficiency in recovering nutrients and in directing pollutants as heavy metals into final sinks. Sludge composting with subsequent use in landscaping does not only show an unfavorable environmental balance, but it is the only relevant route leading to additional CED and Global Warming Potential emissions and to the highest transport volume. Altogether, the outcomes of this study provide a sound basis to further develop national strategies for resource recovery aimed to optimize trade-offs between different economic and environmental objectives.

Interlinking the Renewable Electricity and Gas Sectors: A Techno-Economic Case Study for Austria

Achieving climate neutrality requires a massive transformation of current energy systems. Fossil energy sources must be replaced with renewable ones. Renewable energy sources with reasonable potential such as photovoltaics or wind power provide electricity. However, since chemical energy carriers are essential for various sectors and applications, the need for renewable gases comes more and more into focus. This paper determines the Austrian green hydrogen potential, produced exclusively from electricity surpluses. In combination with assumed sustainable methane production, the resulting renewable gas import demand is identified, based on two fully decarbonised scenarios for the investigated years 2030, 2040 and 2050. While in one scenario energy efficiency is maximised, in the other scenario significant behavioural changes are considered to reduce the total energy consumption. A techno-economic analysis is used to identify the economically reasonable national green hydrogen potential and to calculate the averaged levelised cost of hydrogen (LCOH2) for each scenario and considered year. Furthermore, roll-out curves for the necessary expansion of national electrolysis plants are presented. The results show that in 2050 about 43% of the national gas demand can be produced nationally and economically (34 TWh green hydrogen, 16 TWh sustainable methane). The resulting national hydrogen production costs are comparable to the expected import costs (including transport costs). The most important actions are the quick and extensive expansion of renewables and electrolysis plants both nationally and internationally.

The influence of particle size on the potential of enhanced basalt weathering for carbon dioxide removal - Insights from a regional assessment

Enhanced weathering through basalt application on agricultural land represents a proposed strategy for the removal of carbon dioxide from the atmosphere. It has been shown that enhanced weathering is principally feasible on a global scale, but there is still uncertainty with respect to the predicted drawdown in a given timeframe. This information is however vital to evaluate, if enhanced weathering should be further considered as a factor to alleviate the impact of the climate crisis. With this in mind, this article reviews of the current state of research and estimates the CO2 drawdown for scenarios using basalt powders of different particle size distribution (<100 μm, <10 μm and <1 μm). Calculated with a modified shrinking core model, the amount of powder dissolved within a timeframe of 10 years is approximately 16% (<100 μm), 55% (<10 μm) and 99.9% (<1 μm). This corresponds to a gross CO2 removal of 0.045 t CO2 t−1 of rock (<100 μm) and 0.153 t CO2 t−1 of rock, (<10 μm). We evaluate our results on regional scale through a case study for Austria, including emissions from mining, comminution, application and transport. Assuming an average distance of 300 km from mine to field, the net CO2 drawdown decreases to approximately 0.027 t CO2 t−1 of rock (<100 μm) or 0.096 t CO2 t−1 (<10 μm), when rail transport is used. For truck transport, the numbers are reduced to −0.030 t CO2 t−1 of rock (<100 μm) or 0.039 t CO2 t−1 (<10 μm), respectively. Accordingly, at the current CO2 intensity, transport related emissions may cancel out any drawdown if grain sizes (<100 μm) are used. Our estimates suggest that enhanced weathering will only significantly contribute to net CO2 drawdown if grain sizes (<10 μm) are used. Under these conditions the large-scale application of particles with a diameter <10 μm may remove about 2% of Austria's annual Greenhouse gas emissions. We discuss challenges towards this goal, including the enormous amounts of rock needed and the energy requirement related to grinding, as well as uncertainties related to actual field weathering rates. Those uncertainties hinder the precise quantification of CO2 drawdown as of now. While enhanced weathering remains a promising path for climate change mitigation, further research at laboratory and field scale is required to put this technology to optimal use.

Tourism mobility and climate change - A review of the situation in Austria

This paper reviews and assesses the current state of knowledge on the complex relationship between tourism travel and climate change for the case study of Austria, taking into account developments to date and expected future trends of tourism-related transport and their impacts on greenhouse gas emissions as well as impacts of climate change on tourist travel. Three quarters of tourists travel to and from Austria by car and approximately 10% by plane, contributing significantly to the sector's GHG emissions. Should pre-COVID 19 trends continue, an expansion of further distant home markets and an increase of guests arriving by plane can be expected. Low-carbon technologies, intelligent mobility management and societal trends towards shared mobility solutions can improve the environmental performance of tourist travel but will not suffice to achieve the Paris Agreement's climate targets. Further strong incentives will be necessary to avoid these unsustainable forms of mobility and shift trips to climate-friendly modes of transport and the number and distance of tourism trips can be reduced by focussing marketing on closer rather than long-distance home markets and promotion of longer stays. Local tourism stakeholders in Austria can contribute by awareness-raising campaigns and promoting sustainable mobility solutions at the destinations. Politics need enable this shift by setting framework conditions such as full incorporation of climate costs for all modes of travel. Management implications: To reduce travel related GHG emissions significantly, tourism cannot only rely on technological solutions (electric vehicles) and trends (sharing) but must also initiate a shift from air and private road transport to rail and public transport. This requires measures that offer incentives (fast and direct train and bus connections, climate-friendly local transport, luggage services, attractive all-in packages, etc.), but also a focus on closer rather than long-distance home markets, promotion of longer stays and awareness-raising campaigns for local stakeholders and tourists. The awareness created by the COVID-19 and climate crises can be seen as an opportunity to take these measures. • Tourist travel in Austria contributes significantly to the sector's GHG emissions. • Carbon-intensive travel modes, particularly car and long-distance flights, dominate. • Technological solutions and societal trends can only partially solve the problem. • Strong incentives are needed to shift to climate-friendly modes of travel. • The sector should promote closer source markets and longer stays to reduce travel.

Internationalisation, Brexit, and the EU academic system: a case study in Austria

ABSTRACT The withdrawal negotiations after the United Kingdom (UK) voted to leave the European Union (EU) have fuelled discussions concerning the expected repercussions on higher education and research in Europe and call for discussing Brexit against the backdrop of internationalisation and the role of the UK in the European higher education and research landscape. When analysing Brexit as a counter development to internationalisation efforts, the question arises as to how institutions in different EU countries deal with and adapt to the new situation that is susceptible to substantially changing the European higher education landscape. By taking Austria as an example and by comparing our findings with other European countries, we study the responses of higher education institutions (HEIs) in the aftermath of the Brexit vote. To understand if and how Austrian HEIs prepared for Brexit, we conducted semi-structured expert interviews with representatives of International Relation Offices. Despite the awareness that Brexit might have negative consequences, the institutions mainly adopted a ‘wait-and-see’ attitude. The institutions justified this rather passive response by highlighting the uncertain outcome of the Brexit negotiations. However, they also showed a commitment to finding solutions and new strategies once the terms of the UK leave are set.

Evaluation of a profile comparison system for the inclusion of people with disabilities in horticulture: A case study in Austria.

To promote the successful and sustainable inclusion of people with disabilities in different activities such as work, more precise job matching efforts may be of value, especially because people with disabilities are employed at a lower rate than people without disabilities. Requirement profiles as well as profile comparisons have not yet been recorded for horticultural work processes. The aim of this study was to document precisely the work process of the cuttings production of the flower tradescantia and to compare the capabilities of people with disabilities with the requirements for this work process for the purpose of verifying that the tool employed was usable. A skilled worker performed the cuttings production of tradescantias according to good horticultural practice. Additionally, five people with disabilities participated in this study. On the one hand, a structured questionnaire was used to collect the data. On the other hand, the work processes were documented with video recordings and described related to REFA (Association for Work Design, Business Organization and Corporate Development) and evaluated according to IMBA (Integration of People with Disabilities into the Working Environment). Apart from the too long working hours, the work in the cuttings production was feasible for the five subjects who had different types of disabilities. There were situations of underchallenges of different degrees, but no overchallenges. It was necessary to assess each subject individually for the risk of accident. IMBA proved to be an effective tool to evaluate and analyse work activities for the purpose of including people with disabilities into horticultural work processes. Thus, it has the potential to facilitate a socially sustainable and skill-oriented work participation for persons with disabilities.

Optimal planning of thermal energy systems in a microgrid with seasonal storage and piecewise affine cost functions

The optimal design of microgrids with thermal energy system requires optimization techniques that can provide investment and scheduling of the technology portfolio involved. In the modeling of such systems with seasonal storage capability, the two main challenges include the low temporal resolution of available data and the non-linear cost versus capacity relationship of solar thermal and heat storage technologies. This work overcomes these challenges by developing two different optimization models based on mixed-integer linear programming with objectives to minimize the total energy costs and carbon dioxide emissions. Piecewise affine functions are used to approximate the non-linear cost versus capacity behavior. The developed methods are applied to the optimal planning of a case study in Austria. The results of the models are compared based on the accuracy and real-time performance together with the impact of piecewise affine cost functions versus non-piecewise affine fixed cost functions. The results show that the investment decisions of both models are in good agreement with each other while the computational time for the 8760-h based model is significantly greater than the model having three representative periods. The models with piecewise affine cost functions show larger capacities of technologies than non-piecewise affine fixed cost function based models.

How does a social practice perspective add to the development of policy instruments to reduce consumption-based CO2 emissions? A case study of Austria

ABSTRACT While current policies aiming at a reduction of greenhouse gas emissions seem to be successful from the territorial perspective of industrialized countries, emissions are still increasing at the global level. The term weak carbon leakage describes a situation where an increase in consumption in developed countries leads to growing emissions in less developed countries. This effect is strongly related to phenomena like globalization and outsourcing of production. As a consequence, a large part of daily consumed products are imported and include embodied emissions (i.e. direct and indirect emissions that occur in the regions of production). For the development of effective policy instruments addressing consumption-based-emissions (CBE) embodied in these international products and processes, it is essential to apply a consumption-based approach (CBA), including both consumer-oriented policies, focusing on final demand, and producer-oriented policies, focusing on industry. Since a considerable share of consumption behaviour is performed by routines, habits and within social practices (cooking, working or shopping), CBE due to consumer behaviour are analysed in this paper by applying the social practices (SP) approach to the case of Austria. Based on this approach the development of effective policy instruments addressing a reduction of CBE by three types of interventions (re-crafting, substituting and interlocking) are discussed for the main hotspots of Austria’s CBE: construction and mobility. Key policy insights An SP perspective enriches the development of CBE policy instruments by shifting the focus of interventions from individual motivations (conscious consumption) towards the constitutional frame and the particular practice-setting which determines consumer behaviour. Consumption sectors such as construction and mobility are most often embedded in behavioural interlocking (e.g. commuting), calling for practical policy mixes to address this complex interplay of practices. The SP approach demonstrates that CBE can be addressed also by single instruments (e.g. changing a regulation, favouring the avoidance of certain practices or materials offered/used) only.

Exergy analysis of district energy systems and comparison of their exergetic, energetic and environmental performance

This paper investigates the advantages of performing exergy analysis for thermodynamic systems consisting of a district heating network (DHN) by comparing the exergy performance with energetic and environmental performance of three case studies in Austria. Furthermore, the effect of influential parameters such as energy source type, conversion technology, supply/return temperature and reference temperature on exergy performance of the system was investigated. An initial literature review and analysis of the case studies showed that the most influential factor on exergy performance of a system was the type of energy source and its conversion technology. Although lowering the supply temperature of DHN can increase the exergy efficiency of the system, changing reference temperature did not show a clear relationship with exergy efficiency. Finally, no clear relationship between energy and exergy efficiencies of the system was discovered; nevertheless, the higher the exergy efficiency of a system the lower the direct CO2 emissions from it.

Exergy analysis of district energy systems and comparison of their exergetic, energetic and environmental performance

This paper investigates the advantages of performing exergy analysis for thermodynamic systems consisting of a district heating network (DHN) by comparing the exergy performance with energetic and environmental performance of three case studies in Austria. Furthermore, the effect of influential parameters such as energy source type, conversion technology, supply/return temperature and reference temperature on exergy performance of the system was investigated. An initial literature review and analysis of the case studies showed that the most influential factor on exergy performance of a system was the type of energy source and its conversion technology. Although lowering the supply temperature of DHN can increase the exergy efficiency of the system, changing reference temperature did not show a clear relationship with exergy efficiency. Finally, no clear relationship between energy and exergy efficiencies of the system was discovered; nevertheless, the higher the exergy efficiency of a system the lower the direct CO2 emissions from it.