Reducing return temperatures in district heating (DH) networks is crucial for improving overall efficiency, minimising thermal losses, and enabling the integration of renewable energy sources. Achieving this requires a detailed understanding of DH substations performance, as faults or inefficiencies in substations are a common cause of elevated return temperatures. This case study introduces a data-driven approach for fault detection and diagnosis (FDD) in DH substations, aiming to identify such inefficiencies and support targeted performance improvements. The methodology is implemented in a Python-based tool that analyses and visualises smart meter data collected from the primary side of substations. The tool offers geospatial mapping, performance indicators (e.g., return temperature, hydraulic capacity utilization), and metadata filtering (e.g., building type). Using this approach, four recurring fault patterns are identified. To support fault handling prioritisation, the tool segments inefficient substations through scatterplot visualisations. The proposed approach offers utility companies a means to enhance system reliability, reduce emissions, and improve operational performance by systematically identifying and addressing performance issues.
Food manufacturing facilities are a crucial industry for many national economies. However, maintaining a sterile, clean environment they require also demand large amounts of energy and fuel, necessitating in-depth scientific studies to conserve energy in such complex environments. This study designed a unique, large-scale, and industrial-level waste heat recovery (WHR) system with an 18-month implementation within 15 tunnel ovens at a Biscuits and Wafers Industry (BWI) plant in Yemen, a country facing multiple energy challenges. Initial measurements indicated that up to 60% of thermal energy was delivered within the exhaust gases at 150–250 ℃, with a cumulative waste energy of up to 6,000 MWh/year. To overcome this, modular heat pipe systems with deionized water and a sintered copper wick were incorporated to preheat combustion air. Material integrity was verified through Helium leak testing (<1*10−9 mbar*L/s) and monthly ATP bioluminescence swabbing (<10 RLU), providing empirical evidence of zero cross-contamination and HACCP compliance. The proposed system had thermal efficiencies (η) of 36–42%, and exergy efficiencies (ψ) of 22–28%, indicating that an energy saving of more than 3,000 MWh/year and a reduction of about 650 t CO2 emissions could be achieved. Economic analysis resulted in a very competitive simple payback period of 4.1–4.6 years and an Internal Rate of Return (IRR) of 20–22.3%. Besides, the proposed design also offers validated design parameters and SCADA-based control strategies to scale up carbon-neutral thermal recovery in the global food manufacturing industry. It also provides economic standards and operational values for wider industry applications.
In smart cities, reliable, energy-efficient power supply is crucial, highlighting the need for smart grids (SGs). Continuous advancements have enhanced grid resilience, precision, and efficiency through improved communication and collaboration between components. SGs reduce power outages, improve energy consumption control, and integrate renewable sources. Utilities benefit from lower costs and enhanced security. This paper explores the role of advanced communication techniques in SGs, focusing on how technologies like IoT sensors and smart meters enhance energy distribution, promote sustainability, and support real-time data flow for better system control in smart cities.
High-temperature solid oxide cell (SOC) technology is a promising solution for peak shaving and valley filling in intermittent renewable energy microgrids due to its high efficiency and reversibility. Energy conversion is typically done in units of one charge/discharge cycle; however, a precise definition of the SOC system efficiency in continuous switching cycles has not yet been found, particularly lacking unrestricted quantification of reversible efficiency and mode scheduling optimization. This paper proposes, for the first time, the concept of generalized reversible efficiency (GRT) for SOC systems, along with a novel deconstruction and quantification strategy to solve the optimal GRT of such systems over an entire cycle. Specifically, the switching efficiency analysis is based on an energy-flow model of the reversible SOC system, which incorporates a secondary heat recovery process. An algorithmic strategy consisting of an improved decomposition-based multi-objective differential evolution algorithm is designed to optimize GRT under multiple constraints. Results indicate that GRT can be converted into cycle P2G2P (Power to Gas to Power) in any direction. The global maximum GRT is around 60.4%, occurring at the lower point of the medium capacity (denoted as gamma, gamma approximate to 160). The optimal GRT decreases with increasing gamma, exhibits a trade-off with the discharge efficiency, and is affected by thermal dissipation and internal energy losses, especially during discharge.
As a widely used grinding tool in industrial production, the superabrasive diamond grinding wheel has attracted considerable attention due to its high hardness, high wear resistance, and high thermal conductivity. It shows excellent performance in the machining process. However, with the use of the process, the grinding wheel experiences corresponding wear and tear. To ensure production quality, grinding wheel dressing technology has become an indispensable key link in industrial production. In response to the ever-increasing production demand, relevant scholars of grinding wheel dressing methods will focus on the mechanical, special, and composite dressing aspects of combining super-hard diamond grinding wheel dressing methods and related research for continuous improvement and innovation. This paper summarizes various standard grinding wheel dressing methods, analyzes their development status, basic principles, and main features, and looks forward to the future development of wheel dressing, aiming to promote the further development and improvement of grinding wheel dressing technology to meet the ever-increasing demand for production.
