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This study provides the first comprehensive overview of the sustainability performance of the hotel sector in the Himalayan region: Sagarmatha National Park and Buffer Zone, using both environmental, economic, and technical criteria. In particular, the performance of 45 buildings in this region were measured and quantified in terms of life cycle based carbon footprint, life cycle costs, heat loss rate, number of guests, energy consumption, and area. Buildings were classified into three types: traditional, semi-modern and modern. The statistical analysis included testing for significant differences between such categories by means of ANOVA, and determination of the correlation between the same parameters. Results show a significant difference between the buildings’ total carbon footprint and operation stage carbon footprint while, there is no significant difference between the buildings’ life cycle costs. Traditional buildings have on average the largest carbon footprint and life-cycle cost over the typical building lifespan of 50 years of building lifespan. The ANOVA tests highlight how heat loss rate, size of the building and number of tourists in the hotels are significantly different across the building types. A strong positive correlation is observed between environmental impact, economic impact and energy consumption for the household activities, and a negative correlation with the number of guests and building size. By considering several buildings, this study allows to draw new and more general conclusions about effective sustainability strategies in the whole hotel sector in the Himalayan region. In particular, it shows that reducing impacts in the operation stage should be highly prioritized, focusing on reducing energy consumption and heat loss and shifting to the use of renewable energy sources.

Industrial symbiosis (IS) is recognized as an effective practice to support circular economy and sustainable development because it is able to enhance the technical efficiency of production processes, provided IS relationships among companies remain active over the long period. However, although it has been established that IS relationships can be vulnerable to disruptive events that reduce the willingness of companies to cooperate in IS synergies, to date few contributions to the literature focus attention on the events which lead firms to interrupt IS synergies. This paper contributes to the existing literature firstly by highlighting the disruptive events affecting the willingness of companies to cooperate in IS synergies and their causes, and secondly by developing an analytical model to assess the impact of each disruption on physical and monetary flows created among companies by the IS relationship. Specifically, an enterprise input-output (EIO) model is proposed, aimed at mapping the physical and monetary flows resulting from IS synergies among companies. Through this model, disruptive events can be modeled and their impact on the above-mentioned flows can be assessed. A numerical case example illustrates how the model works and how company managers and IS facilitators could use it to evaluate to what degree their current IS relationships may be vulnerable to perturbations. The model could therefore facilitate the design of adequate countermeasures and contribute to the development of perturbation resilient IS relationships. Furthermore, policymakers could adopt the model when designing policy actions to support IS practice.

In many industries, an increasing number of firm owners tie managers’ incentives to sustainability investments. Positive rewards directly increase a manager's total pay when that manager makes sustainability investments, whereas negative rewards directly decrease a manager's pay when those investments are made. Strategic incentive design literature posits that such organizational choices also affect the decisions of a firm's competitors. This paper uses a game-theoretic framework to analyze the effects of sustainability incentives in a setting with two competing firms. In contrast to the existing literature, in the current paper sustainability investments have a demand-enhancing effect and can increase or decrease the unit cost of production, making the current framework more in line with industrial practice. The results show that a firm invests in sustainability only if the demand-enhancing effects outweigh the cost-increasing effects. More importantly, positively rewarding managers for sustainability investments is done in equilibrium only if the innovation capability of the firm is sufficiently high. However, in terms of profits, those positive rewards lead to a prisoner's dilemma. When innovation capability is lower, firm owners use negative rewards and raise their profits. Another finding is that rival firms that cooperate in determining their sustainability incentives increase their profits but do so using negative rewards. These results, which have not been reported in the literature, point to some critical trade-offs in terms of sustainability investments and firm profits when sustainability incentives are considered and are both managerially and academically relevant.

Electrical energy production from renewable energy sources and electrification of consumer energy demand are developments in the ongoing energy transition. These developments urge the demand for flexibility in low voltage distribution networks, on the one hand caused by the intermittency of renewable energy sources, and on the other hand by the high power demand of battery electric vehicles and heat pumps. One of the foremost ways to create flexibility is by using energy storage systems. This paper proposes a method to first optimize the siting, power and capacity rating, technology, and operation of energy storage systems based on the technical and economic value. Secondly the method can be used to make cost- and time-based network planning decisions between network upgrades and network upgrade deferral by energy storage systems. To demonstrate the proposed method, study cases are analyzed of five low voltage distribution networks with different penetrations of photovoltaics, heat pumps and battery electric vehicles. The optimal energy storage systems in the study cases are: flow batteries sited at over 50% of the cable length with a high capacity rating per euro. With the current state of energy storage system development, network upgrade deferral is up to 61% cheaper than network upgrades in the study cases. The energy storage systems can offer additional value by reducing the peak loading of the medium voltage grid which is not taken into account in this research.

Abstract The configuration of a latent heat thermal energy storage (LHTES) is an important factor considered by manufacturers of heat storage systems. In this study, an applicable and low-cost way of improving melting behavior in a rectangular cavity was remarked. There was a preconceived idea that with a single conductive baffle, embedded on the upper wall of the cavity, the melting rate and the amount of heat storage could improve. Therefore, for different locations as well as lengths of a baffle, the heat transfer and melting characteristic of gallium as a phase change material (PCM) in a rectangular cavity were investigated numerically. The cavity has the insulated upper and bottom walls. The sidewalls are regarded to have constant temperatures one higher and another lower than the melting point of gallium. The phase change process is modeled with the fixed grid-based enthalpy-porosity method coupled with the semi-implicit method for pressure-linked equations (SIMPLE) algorithm. The isotherm lines and streamlines, as well as the liquid fraction and Nusselt number on the hot wall, are considered to present the results at a constant Rayleigh number equal to 106. The results show the baffle imposes noticeable improvement on the melting process of gallium in a rectangular cavity by influencing the feature of convective heat transfer. Investigating the different baffle’s locations (LX/L = 0.2 to 0.9) revealed that when the baffle located at the right half of the cavity, melting initiates from the left side, the more amount of PCM melts in comparison with the other cases. Ultimately, the dimensionless location of LX/L = 0.8 demonstrates the best melting characteristic and the most final liquid fraction. The more liquid-fraction, the more energy storing concluded. It also observed a dimensionless height of LY/L = 0.4 represents the most liquid-fraction compared to the heights of LY/L = 0.2, 0.3, and 0.4.