Journal of Engineering and Science Vol. 1 No. 1 (Jan–Jun 2022) presents five foundational studies covering micro‑scale photovoltaic system design (methodical sizing and performance estimation for a 50 Wp solar installation), evaluation of waste coconut shell as an alternative solid biofuel (emphasizing its energy characteristics and combustion viability), comparative routes for converting plastic waste into liquid fuels (highlighting thermochemical methods and their relative yields and product quality), failure analysis of the wheel–rail contact surfaces in an overhead travelling crane (identifying wear and probable contributing operational or material factors), and structural calculation and design of a Type II civil engineering laboratory building at UMSU Medan (addressing load analysis and code‑compliant member sizing for safety and serviceability).