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Title: Renewables energies in Colombia and the opportunity for the offshore wind technology. Some comments that still need a modification are given as follows.R/ Thank you for your comments. Enclosed we will answer each one of them. Please avoid abbreviation in Abstract. R/ We removed abbreviations in the abstract as follows:"Global offshore wind technology shows increasing progress evidenced in the recent reports of wind power capacity, expectations of market expansion and international research projects. Colombia is privileged with several types of natural resources (e.g. wind, sun, water) but there is not a clear legal context to regulate sustainable and safe exploitation of the offshore wind energy considered nonconventional. The development of offshore wind technology in Colombia could attend the energy demand when the hydroelectric system presents low electricity generation during dry hydrological conditions and El Niño -South Oscillations events. This paper analyses international actions that have motivated different countries to establish strategies to reduce CO2, and their advances and challenges in implementing offshore wind technology. The review of the administrative framework of renewable energy in Colombia proved the lack of information for implementing offshore wind technology. Furthermore, the analysis of several studies of marine energies showed the need to increase the knowledge of offshore wind energy. The local applying projects to generate electricity from non-conventional renewable energies are not considering offshore wind energy projects. Hence, this research analyzed wind speed and calculated wind power density at different height levels, what evidenced magnitudes and positive trends what justify to increase the research in offshore wind energy in Colombia. As a result, the present document compiles technical, economic, administrative and legal information of the renewable energies in Colombia that may be used for taking decisions of different stakeholders and evidences the potential implementing offshore wind farms in areas near to the Colombian Caribbean coast. Colombia has great resources to implement offshore wind energy technologies, reducing the dependence on fossil fuels and substituting other systems when they cannot guarantee the energy offer."  A Literature Section needs to be included in the writing before RM section. You need to differ between literature analysis and your study analysis. In the LR section, you need to deeply analyse previous related studies and reveal the knowledge gaps and inconsistencies in the literature, then relate them to the objective of your study. The results analysis and discussion are presented after the methodology section.R/ Thank you for the suggestion. As we commented in the Revision #1, the methodology that we exposed for the manuscript (RM section), to be considered as a Review Article and also a Research article itself, is to describe the way how we collected and presented data in each section. Therefore, the manuscript is arranged accordin...

Cleaner production is a lively concept in which new procedures and technologies constantly emerge introducing methods and practices to prevent damages to the environment. A broad range of cleaner production initiatives contribute to sustainable development not only through the efficient management of resources and energy, but also through the development of new and smart technologies, new ways of assisting policies development, and organizing supply chains, sectors and individual companies. The authors of this Virtual Special Issue sought to introduce first-hand knowledge and discussions identifying and highlighting the ways cleaner production can contribute to reach the United Nations sustainable development targets. The intent of the Virtual Special Issue is to provide an overview of the recent trends that cleaner production practitioners/researchers are following in the chase of the sustainable development goals, and in this context, this editorial was designed to summarize and underscore the link between cleaner production concepts and practices and the sustainable development goals. An adequate response to this challenge required scientific knowledge and reassessment of the papers ensuring that the science is responsive to the evolving needs of sustainable development. This Virtual Special Issue of the Journal of Cleaner Production is mainly dedicated to the 7th International Workshop on Advances in Cleaner Production, held at Universidad de La Costa, Barranquilla, Colombia on 21-22 June 2018. Based upon the examination of the papers of this Virtual Special Issue, the authors were able to establish that there is an pressing need for research on the assessment on which/when cleaner production interventions are more effective; inter and multidisciplinary cooperation among social and technical scientists to distinguish and address the cleaner production/sustainable development goals interactions and connect cleaner production solutions and large-scale sustainability approaches.

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Thermoelectric generation is an alternative to recover some of the wasted energy trough an exhaust of the internal combustion engines. This paper assesses the performance of a thermoelectric generator with 20 modules by implementing a waffle heat exchanger. Experimental results showed a variable range of power recovery from 57.87 W to 71.13 W for B10, B5, and Diesel. The highest energy conversion efficiency of the aforementioned thermoelectric device was of 3% with the highest load and the fastest rotational speed. Also, the recovery process reduced gaseous emissions such as CO, CO2, NO, NOX, and HC. Additionally, the smoke opacity per kWh is reduced at significant levels of operations such as 2.42% when using diesel, 2.65% when using B5 and 3% when using B10. However, when using biodiesel blends, NOx emissions were increased. Overall the biodiesel resulted in a higher power recovery performance versus the diesel.

Hotels are among the most energy intensive tourism facilities. To monitor and control the monthly and yearly energy consumption in hotels, different indicators have been proposed. These indicators, developed on yearly or annual basis, do not permit rapid detection and mitigation of malpractices and overconsumptions in hotel facilities. Moreover, these indicators do not consider the influence of physical parameters such as outdoor temperature, or, when they do, rather complex coefficients are used, precluding implementation in hotel facilities. This study discusses the use of Energy Performance Indicators to assess and control the electricity consumption in hotels. To this end a new indicator considering the outdoor temperature is introduced. Based on this indicator daily control graphs are developed, allowing a more rapid detection of overconsumptions and malpractices towards a higher electricity efficiency. One advantage of this approach is that no investments are required to implement it. The tools were implemented in two Cuban hotels of different characteristics, where reductions of the electricity consumption in 2014 compared to 2013 of 10 and 11%, were achieved.

Sugar from sugarcane represents 65-70% of the world production of sugar and its production is mainly located in developing countries. The production process requires high amounts of steam and electricity at the different stages, and generates important quantities of residues. A major residue of the sugar production is filter cake (in Cuba: Cachaza), the residue from cane juice filtration. Filter cake causes significant pollution, and in several sugar factories it is considered a waste, posing problems of management and final disposal. This paper reviews recycling and recovery opportunities of filter cake (and bagasse) and experimentally studies the use of filter cake as fuel at the sugar factory. Filter cake may e.g. be used as a fertilizer/soil improver directly applied on the fields or after composting. During its decomposition, it generates, however, an acid leachate and emits significant amounts of greenhouse gases. Moreover, the experimental part of the paper shows that blends of filter cake with bagasse can be combusted in industrial boilers in sugar factories, and that loose, non-vitrified ashes with a similar appearance as bagasse ash are obtained. This results in lower volumes and masses of residues to be transported, so that transportation costs are reduced. Moreover, it gives a new economic value to the filter cake, and reduces its environmental impact. When all filter cake would be combusted blended with bagasse, about 25% more ash would be obtained than for bagasse and the trace element composition would comply with the regulatory limits for use as fertilizer/soil improver.

The involvement of universities is crucial to identify how Cleaner Production strategies are formed in practice so that companies integrate sustainability into their strategies. This paper discusses the experience of establishing and operating the Cleaner Production Center at the University of Cienfuegos. From 2008 to 2011, the University of Cienfuegos, the Free University of Brussels (Belgium) and the University of Leuven (Belgium) implemented a project, financially supported by the Flemish Interuniversity Council (Belgium) allowing establishing a Cleaner Production Center at the University of Cienfuegos. This first project was followed by a second University of Cienfuegos-University of Leuven one. So far, the collaboration allowed to establish a master program on Cleaner Production that constitutes a bridge between the university and the production and service sector, allowing to promote and implement cleaner production strategies. 34 master students graduated during two graduations and a third one is ongoing. Among the most important results of the master thesis were the yearly reduction of the emission of 60 000 t/a of carbon dioxide equivalent and of the electricity consumption by 400 MWh/a at a cement plant. Research activities on Cleaner Production were upgraded through the collaboration resulting in several publications in peerreviewed journals with impact factor. This type of North-South cooperation aided establishing and developing the center, by transferring expertise and experience and by providing part of the necessary funding which is difficult to raise by developing economies. This case study offers an interesting practice example about developing academic (training, research) values on Cleaner Production.