by Xiang Li  , Yuan Xue  , Ryan Dehoff  , Costas Tsouris  and Patricia Taboada-Serrano

Received: 09 April 2020;  Published: 09 May 2020;  doi: 10.21926/jept.2002007

Hierarchically-structured, electro-catalysts consisting of a titanium core with controlled macro-porosity and a thin titania surface-layer with controlled nano-porosity were synthesized via combination of additive manufacturing and in-situ anodization. The electrodes were tested for hydrogen evolution reaction and depicted competitive electro-catalytic activities, with Tafel slopes between 40 and 56 mV dec-1. The electrodes also depicted competitive onset and over potentials when compared with other electrode alter [...]

by Megan Schutt  and Harvey Seim

Received: 10 April 2020;  Published: 30 April 2020;  doi: 10.21926/jept.2002006

SODAR wind profiler measurements from a land-based site within 1000 m of the coastal ocean are compared with predicted wind profiles based on upwind conditions and a stability-based model. The thermally dynamic influence of the Gulf Stream near the site of measurement, Cape Hatteras, has been found to complicate wind speed estimation at height through its impacts on atmospheric stability and the resulting changes to wind shear. The COARE 3.0 algorithm was used to calculate a Monin-Obukhov Similarity Theory (MOST) s [...]

by Max F. Platzer  and Nesrin Sarigul-Klijn

Received: 28 January 2020;  Published: 29 April 2020;  doi: 10.21926/jept.2002005

The current status of a project is described which aims to demonstrate the technical and economic feasibility of converting the vast wind energy available over the globe’s oceans and lakes into storable energy. To this end, autonomous high-performance sailing ships are equipped with hydrokinetic turbines whose output is stored either in electric batteries or is fed into electrolysers to produce hydrogen which then is compressed and stored in tanks. In the present paper, the previous analytical studies which showed [...]

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 Tyler Campbell  and Sergey Stolbov

Received: 16 February 2020;  Published: 20 April 2020;  doi: 10.21926/jept.2002003

In the search for new efficient photo-catalysts for hydrogen production through water splitting, the main attention has been paid to tuning the band gap width and its position with respect to vacuum level. However, actual electro-catalytic activity for the water oxidation reaction on a catalyst surface is no less important than those quantities. In this work we evaluate from first principles the thermodynamics of the reaction on relatively new candidates for water splitting: two-dimensional C2N and that doped with [...]

by Ryosuke Oochi  , Kengo Aoyama  and Akira Ueda

Received: 27 November 2019;  Published: 12 February 2020;  doi: 10.21926/jept.2001002

In order to achieve advancement in zero-emission geothermal power generation for fixing the CO2 in the geothermal fluids to the carbonate minerals after binary power generation and reinjection of the fluid into the reservoir, batch-type experiments and geochemical simulations of CO2-andesitic pyroclastic rock interaction (tuff from Oku-Aizu geothermal area) were performed at 150 °C with and without CO2 gas for 15 days. Despite the low Ca content (0.9% wt.%) in the rock, the Ca2+ concentrations in the solutions that [...]

by Nikolai A. Zarkevich

Received: 30 September 2019;  Published: 06 January 2020;  doi: 10.21926/jept.2001001

Most power plants produce electricity by converting a mechanical motion into alternating current (AC). Photovoltaic solar panels convert an electromagnetic flux of light into direct current (DC). In general, electric energy can be harvested from a flux in the environment or from a change of the environment itself. One can produce electricity from mechanical, chemical, thermal, electromagnetic (light), or another physical flux, or from a change of temperature, chemical composition, or a physical field: gravitationa [...]

by Misirkhan A. Talybov  , Lala A. Azizova  and Ilmutdin M. Abdulagatov

Received: 24 September 2019;  Published: 24 December 2019;  doi: 10.21926/jept.1904006

Background: In the present study, vapor-pressures of three geothermal fluids from Baden-Baden geothermal field (Kirchenstollen, Friedrichstollen, and Murquelle, southeastern region of Germany) were measured over the temperature range of 274–413 K. The combined expanded uncertainty of the temperature and vapor-pressure measurements at 95% confidence level with a coverage factor of k = 2 were estimated to be 0.01 K and 1–3 Pa at low and 10–30 Pa at high temperatures, respectively. The measured values of vapor-pressur [...]

by Anna Karmazina  and Brent S. Steel

Received: 18 November 2019;  Published: 24 December 2019;  doi: 10.21926/jept.1904005

The 2013 Pacific Coast Action Plan on Climate and Energy signed by the Governors of Oregon, California, and Washington and the Premier of British Columbia, launched a broadly announced public commitment to reduce greenhouse gas emissions through multiple strategies. Those strategies include the development and increased use of renewable energy sources. The initiative recognized that citizens are both a central component to abating greenhouse gas emissions with regard to their energy use behaviors, and are important [...]

by Iman Rahimi  , Reza Behmanesh  and Abdollah Ahmadi

Received: 21 May 2019;  Published: 15 November 2019;  doi: 10.21926/jept.1904004

The aim of this paper is the scientometric analysis of articles on “scheduling in renewable energy” that have been published between 2000 and 2017. For this purpose, the terms “scheduling in renewable energy” and “unit commitment in renewable energy” have been searched. We have found 1009 articles in the Scopus database which include the terms mentioned above. VOSviewer and CiteSpace, as two well-known the scientometric analysis tools, have been used. Keywords analysis and citation analysis are two analysis methods [...]