by Anudeep Katepalli  , Thiraj Mohankumar  , Meher Saketh Gandharapu  , Sagar Shrestha  , Anton Harfmann  , Mathias Bonmarin  , John Krupczak  and Donglu Shi

Received: 06 July 2025;  Published: 11 September 2025;  doi: 10.21926/jept.2503013

Indoor environments offer a unique opportunity for photon recycling using LED-based illumination, particularly to address energy limitations of solar photovoltaic (PV) systems during nighttime or in low-light conditions. This study presents an optical and electrical performance evaluation of silicon-based photovoltaic (SPV) panels operating under controlled indoor LED lighting. Despite the low irradiance (~1.4 mW/cm²), significant power output was achieved through engineer [...]

by Franco David Hessling Herrera

Received: 01 May 2025;  Published: 25 August 2025;  doi: 10.21926/jept.2503012

The tariff policy for energy services is a fundamental issue for today's societies, especially for end users, including residential, commercial, and industrial. The main objective of this paper is to propose a statistical method to calculate, compare, and evaluate policies of this nature. To this end, firstly, it is intended to rethink an old concept on this type of policy, the principle of fairness and reasonableness, through the linkage with the perspective of human rights, specifically with t [...]

by Zhichao Wang  , Daisuke Mori  , Sou Taminato  , Yasuo Takeda  , Osamu Yamamoto  and Nobuyuki Imanishi

Received: 28 April 2025;  Published: 13 August 2025;  doi: 10.21926/jept.2503011

Solid lithium-ion conducting polymer electrolytes are attractive candidates for battery applications because they are flexible and less flammable, and can be easily prepared as large-sized thin films. However, the room temperature conductivity of conventional polymer electrolytes is relatively low, and detrimental lithium dendrite formation is observed at high current density. In this study, a composite polymer electrolyte of polyethylene oxide (PEO) with lithium bis(trifluoromethanesulfonyl)imi [...]