EnvironSciRN: Other Energy & Environmental Science (Topic)最新文献

{"title":"Solar Desalination Unit Coupled with a Novel Humidifier","authors":"E. El-Said, M. Omara, M. Dahab, Gamal B. Abdelaziz","doi":"10.2139/ssrn.3885515","DOIUrl":"https://doi.org/10.2139/ssrn.3885515","url":null,"abstract":"Abstract The solar desalination system is experimentally investigated according to humidification dehumidification methodology (HDH) with hot air stream flow and heat pump as a condensation unit. The effects of high frequency ultrasound atomizer number, water height and hot air stream flow rate on distillate yield are studied. The results illustrated that increasing of atomizer number and decreasing water height increases the daily distillate production. The maximum daily freshwater productivity occurred at six atomizer number with an increase of 38.6% and 115% compared with atomizer number four and two, respectively. Furthermore, water height at 1 cm is the most efficient with an increment of 16% and 28.6% compared with 2 cm and 3 cm, respectively. The optimum hot air stream flow rate is 0.011 kg/s with an increment of 36.88%, 31.07%, 6.48%, 11.72%, 23.52% and 38.60% compared with 0.009, 0.010, 0.013, 0.014, 0.016, and 0.017 kg/s, flow rates, respectively. The air mass flow rate has a significant impact on system performance. The maximum gain output ratio (GOR) of the system is about 1.54. The daily production reaches 7.72 kg∖day, the system energy efficiency is 33.84% and 1.43% exergy efficiency the estimated cost is 0.0112 US$/L.","PeriodicalId":151979,"journal":{"name":"EnvironSciRN: Other Energy & Environmental Science (Topic)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130952028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Management of Renewable Energies and Environmental Protection","authors":"R. Petrescu, R. Aversa, A. Apicella, S. Kozaitis, T. Abu-lebdeh, F. Petrescu","doi":"10.3844/AJEASSP.2017.919.948","DOIUrl":"https://doi.org/10.3844/AJEASSP.2017.919.948","url":null,"abstract":"The purpose of this project is to present an overview of renewable energy sources, major technological developments and case studies, accompanied by applicable examples of the use of sources. Renewable energy is the energy that comes from natural resources: The wind, sunlight, rain, sea waves, tides, geothermal heat, regenerated naturally, automatically. Greenhouse gas emissions pose a serious threat to climate change, with potentially disastrous effects on humanity. The use of Renewable Energy Sources (RES) together with improved Energy Efficiency (EE) can contribute to reducing energy consumption, reducing greenhouse gas emissions and, as a consequence, preventing dangerous climate change. At least one-third of global energy must come from different renewable sources by 2050: The wind, solar, geothermal, hydroelectric, tidal, wave, biomass, etc. Oil and natural gas, classical sources of energy, have fluctuating developments on the international market. A second significant aspect is given by the increasingly limited nature of oil resources. It seems that this energy source will be exhausted in about 50 years from the consumption of oil reserves in exploitation or prospecting. \"Green\" energy is at the fingertips of both economic operators and individuals. In fact, an economic operator can use such a system for both own consumption and energy trading on the domestic energy market. The high cost of deploying these systems is generally depreciated in about 5-10 years, depending on the installed production capacity. The \"sustainability\" condition is met when projects based on renewable energy have a negative CO2 or at least neutral CO2 over the life cycle. Emissions of Greenhouse Gases (GHG) are one of the environmental criteria included in a sustainability analysis, but is not enough. The concept of sustainability must also include in the assessment various other aspects, such as environmental, cultural, health, but must also integrate economic aspects. Renewable energy generation in a sustainable way is a challenge that requires compliance with national and international regulations. Energy independence can be achieved: - Large scale (for communities); - small-scale (for individual houses, vacation homes or cabins without electrical connection).","PeriodicalId":151979,"journal":{"name":"EnvironSciRN: Other Energy & Environmental Science (Topic)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125629155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}