by Ann Lee  and Shaokoon Cheng

Received: 26 March 2023;  Published: 18 September 2023;  doi: 10.21926/jept.2303029

In the context of decarbonization efforts, heat pump water heaters (HPWHs) offer an attractive solution over conventional electric resistance type hot water systems due to their 2-3 times higher efficiency. However, the high manufacturing costs and taxes associated with using hydrofluorocarbon (HFC) refrigerant make HPWHs expensive. As a means to tackle this issue, this paper explores the use of propane (R290) as a refrigerant in HPWHs. The study involves an experimental comparison of R290 and R134a, with refrigera [...]

by Kamal A.R. Ismail  , Fatima A.M Lino  , Jorge R. Henriquez  , Mohamed Teggar  , Abdelghani Laouer  , Muslum Arici  , Amani Benhorma  and Daniel Rodríguez

Received: 12 June 2023;  Published: 19 October 2023;  doi: 10.21926/jept.2304031

The building sector is rated as a big consumer of electric energy and emissions, responsible for about 40% of final electric energy consumption. As a result, the Paris Agreement 2015 set a goal for buildings and the construction sector to reach a nearly zero-carbon stage by 2050. This urged most countries to create regulations for the construction sector and invest in energy efficiency programs. The present paper aims to present an updated review of building energy-saving solutions and techniques to contribute to c [...]

by Foad Haeri  , Deepak Tapriyal  , Christopher Matranga  , Dustin Crandall  and Angela Goodman

Received: 05 September 2021;  Published: 05 November 2021;  doi: 10.21926/jept.2104046

Contact angles were measured for CO2-brine interactions on 20 different rocks that represent the properties of various CO2 storage depositional environments to characterize the wettability during geologic carbon storage. Three different CO2 phases (gaseous, liquid, and supercritical) were considered to investigate the effect of pressure and temperature. Bubbles were studied in two groups of larger and smaller than 500 μm, the latter being more relevant to pore scale. Variation was observed among contact angle measu [...]

by Manuel Legree  , Jocelyn Sabatier  , Fabrice Mauvy  , Abdel Salam Awad  , Matthieu Faessel  , Frederic Bos  and Jean-Louis Bobet

Received: 04 March 2020;  Published: 28 April 2020;  doi: 10.21926/jept.2002004

This paper focuses on hydrogen production for green mobility applications (other applications are currently under investigation). Firstly, a brief state of the art of hydrogen generation by hydrolysis with magnesium is shown. The hydrolysis performance of Magnesium powder ball–milled along with different additives (graphite and transition metals TM = Ni, Fe, and Al) is taken for comparison. The best performance was observed with Mg–10 wt.% g mixtures (95% of theoretical hydrogen generation yield in about 3 min). An [...]

by Rui Wang  , Omar M. Basha  , Husain E. Ashkanani  , Bingyun Li  and Badie I. Morsi

Received: 19 August 2024;  Published: 21 November 2024;  doi: 10.21926/jept.2404022

CO2 capture processes using five chemical solvents were modeled in Aspen Plus V.12.1 for the capture of over 90% CO2 from a 456 ton/hour split flue gas stream containing 12.02 mol% CO2 emitted by the Longview 780 MW power plant (West Virginia, USA). Since the flue gas contained 33.10 ppmv SO2 and 35.47 ppmv NO2, a gas polishing process, using deionized water (DIW), was included in the model for complete scrubbing of SO2 and NO2 from the raw flue gas before the CO2 capture process. The five chemicals used for CO2 ca [...]

by Wisut Chamsa-ard  , Derek Fawcett  , Chun Che Fung  and Gerrard Poinern

Received: 28 September 2020;  Published: 29 December 2020;  doi: 10.21926/jept.2004018

The demand for high-quality freshwater is increasing due to global population growth, intensifying agricultural practices and expanding industrial development. Additionally, many global regions have low levels of rainfall which makes them arid and incapable of supporting large human populations or agriculture. Currently, large quantities of fossil fuels are used to generate the power needed to drive energy intensive desalination processes that deliver high-quality freshwater to many of these regions. However, the u [...]

by Nobuyuki Imanishi  , Tao Zhang  , Daishuke Mori  , Sou Taminato  , Yashuo Takeda  and osamu yamamoto

Received: 21 February 2021;  Published: 08 May 2021;  doi: 10.21926/jept.2102019

Because lithium metal exhibits high specific capacity and low potential, it is the best candidate for fabricating anodes for batteries. Rechargeable batteries fabricated using lithium anode exhibit high capacity and high potential cathode; these can be potentially used to fabricate high energy density batteries (>500 Wh kg-1) that can be used for the development of next-generation electric vehicles. However, the formation and growth of lithium dendrites and the low coulombic efficiency recorded during lithiu [...]

by Despina Vamvuka  , Maria Deli  and Antonios Stratakis

Received: 06 September 2021;  Published: 11 November 2021;  doi: 10.21926/jept.2104047

In this work, the conducted chemical, mineralogical, fusibility, and thermogravimetric analyses and calculated the slagging/fouling indicators for predicting deposition tendencies in boilers to study the ash fusibility behavior of selected agricultural residues and their blends with lignite. Two additives, bauxite, and clinochlore, were used at varying amounts to reduce ash melting, followed by examining their anti-fusion mechanisms. Initial deformation and softening temperatures of biomass materials were low for c [...]

by Udaya Kahangamage  , Yi Chen  , Chun Wah Leung  and Tung Yan Ngai

Received: 02 January 2022;  Published: 18 April 2022;  doi: 10.21926/jept.2202016

The lean-burning limits of hydrogen-enriched Liquefied Petroleum Gas (LPG) have been studied using a Bunsen burner. The lean-burning limits under different conditions are important design considerations in developing gas-fired domestic appliances. In this study, the lean-burning limits of hydrogen-enriched LPG have been obtained across a wide range of Reynolds numbers (600 to 1800) and H2 volumetric fractions (0% to 25%). The results show that the lean-burning limit is increased, on average, by 4.0% to 7.2% for eve [...]

by Fariba Moradipour  , Andreas Markert  , Thomas Rudszuck  , Niklas Röttgen  , Gerald Dück  , Martin Finsterbusch  , Felix Gerbig  , Hermann Nirschl  and Gisela Guthausen

Received: 04 August 2023;  Published: 02 November 2023;  doi: 10.21926/jept.2304032

Charge transfer and mobility are essential for electrochemical processes in batteries, which need to be understood in detail for optimization, especially in the case of all-solid-state batteries. Wide line NMR is well-known in solid-state NMR and allows the quantification of ion mobility in ordered crystalline and amorphous structures. Temperature-dependent 23Na-NMR is sensitive to ion mobility via longitudinal relaxation, but also via line analysis and transverse relaxation. As 23Na is a spin 3/2 nucleus, 23Na-NMR [...]