Preliminary testing results of a diaphragm FPSE

The paper presents design and preliminary testing results of a Free Piston Stirling Engine (FPSE) prototyp operating at low temperature heat sources. The main focus of this work is to demonstrate the construction of the displacer using flexure bellows as a mechanical supporting spring and as a working fluid seal. The power piston, on the other hand, is made of a planar elastomer material in the shape of a disk with a suitable mechanical elasticity, rigidity, and thermal properties to support the range of operating temperatures. A small prototype of the FPSE was built and tested at operating temperature of under 200 oC. The measured operating frequency was 15 Hz, a reciprocating stroke of 8mm and operating pressure close to atmospheric pressure. The prototype was equipped with instruments to measure all the operating parameters. The power output was measured from the p-v diagram using a two-channel oscilloscope. The preliminary results demonstrated the operation concept and reliable start up, but further improvements will be needed to fine tune the reciprocating components and reduce mechanical friction

Experimental investigation of a novel heat pipe and porous ceramic based indirect evaporative cooler

The paper presents laboratory test results of an integrated heat pipe and ceramic tube based evaporative cooling prototype for air conditioning in buildings. The cooler integrates durable porous ceramic tubes as water saturated media materials and heat pipes as efficient heat transfer devices. The ceramic tubes and the heat pipes straddle across two separate air ducts to form a wet and dry channel respectively. The thermal performance of the cooler was measured at various air inlet conditions of temperature, humidity and mass flow rates. The experimental measurements show that the cooling system can provide sufficient cooling as high as 1220 W/m2 of the wet media exposed surface area and depressing ambient temperature to 12℃. Equally, it was measured that the wet bulb effectiveness of the cooler can reach 86%

Preliminary testing results of a diaphragm FPSE

The paper presents design and preliminary testing results of a Free Piston Stirling Engine (FPSE) prototyp operating at low temperature heat sources. The main focus of this work is to demonstrate the construction of the displacer using flexure bellows as a mechanical supporting spring and as a working fluid seal. The power piston, on the other hand, is made of a planar elastomer material in the shape of a disk with a suitable mechanical elasticity, rigidity, and thermal properties to support the range of operating temperatures. A small prototype of the FPSE was built and tested at operating temperature of under 200 oC. The measured operating frequency was 15 Hz, a reciprocating stroke of 8mm and operating pressure close to atmospheric pressure. The prototype was equipped with instruments to measure all the operating parameters. The power output was measured from the p-v diagram using a two-channel oscilloscope. The preliminary results demonstrated the operation concept and reliable start up, but further improvements will be needed to fine tune the reciprocating components and reduce mechanical friction

Experimental investigation of a novel heat pipe and porous ceramic based indirect evaporative cooler

The paper presents laboratory test results of an integrated heat pipe and ceramic tube based evaporative cooling prototype for air conditioning in buildings. The cooler integrates durable porous ceramic tubes as water saturated media materials and heat pipes as efficient heat transfer devices. The ceramic tubes and the heat pipes straddle across two separate air ducts to form a wet and dry channel respectively. The thermal performance of the cooler was measured at various air inlet conditions of temperature, humidity and mass flow rates. The experimental measurements show that the cooling system can provide sufficient cooling as high as 1220 W/m2 of the wet media exposed surface area and depressing ambient temperature to 12℃. Equally, it was measured that the wet bulb effectiveness of the cooler can reach 86%

Residential building energy performance evaluation for different climate zones

The building sector in the Kingdom of Saudi Arabia accounts for a large proportion of energy consumption. This paper investigates energy consumption in residential type A villa buildings constructed by the Ministry of Housing. The study specifically investigates energy consumption of a case building in three climate zones of the country identified in the KSA Building Code (SBC-602E). The software package IES-ve was used to simulate power consumption of the case building taking into account the climate characteristics of each zone. In total 6 cities were considered from the three zones to evaluate and compare annual and monthly power consumption loads of the building. It was found that there is some distinction of energy consumption for heating and cooling in the three zones (e.g., peak monthly power energy consumption for cooling varied from 6.371 MWh in Riyadh (zone1) to 1.663 MWh in Abha (zone3) and no heating requirement for Jaddah (zone 1) while Turaif (zone 3) heating consumption is 23.835 MWh) however, further work is required to identify clearer the climate specifications within each zone to address the excess energy consumption of this type of buildings

Demonstrating a novel configuration of FPSE prototype working at medium temperature range

Numerous FPSE designs have been demonstrated, tested and maybe commercially produced for different applications since Beale had invented the first design of the FPSE. The proposed design of FPSE is intended to operate at atmosphere pressure and low heat source temperature for power generation applications. The proposed design aims to address some of the disadvantages associated to the FPSEs, such as seal leakage, hysteresis losses and side forces, with the considerations of the mechanism and assembly to be simple and straightforward. The focus was on the components and the design of the displacer and the power piston as they are of the main parts in the FPSE influence its operation and performance. The displacer and the power piston have improved by integrating sorts of flexible materials that being used in replace of the typical mechanical springs. The flexible metal component used in replace of the conventional mechanical springs has the properties of elasticity, rigidity, low density and low thermal conductivity beside its cylindrical housing shape. A prototype for the novel configuration with the integration of stainless bellows and rubber diaphragm is built to be work at low and medium temperature range. The engine is gradually improved so that the objectives of the configuration are achieved. The FPSE prototype is demonstrated and tested in the lab to assure that the new configuration is working properly. The engine is new in terms of design mechanical configuration; however, it showed aspiring results

Electric Vehicles: V2G for Rapid, Safe, and Green EV Penetration

Low carbon and renewable energy sources (RESs) are fast becoming a key sustainable instrument in meeting the global growth of electricity demand while curbing carbon emissions. For example, the gradual displacement of fossil-fuelled vehicles with electrically driven counterparts will inevitably increase both the power grid baseload and peak demand. In many developed countries, the electrification process of the transport sector has already started in tandem with the installation of multi-GW renewable energy capacity, particularly wind and solar, huge investment in power storage technology, and end-user energy demand management. The expansion of the Electric Vehicle (EV) market presents a new opportunity to create a cleaner and transformative new energy carrier. For instance, a managed EV battery charging and discharging profile in conjunction with the national grid, known as the Vehicle-to-Grid system (V2G), is projected to be an important mechanism in reducing the impact of renewable energy intermittency. This paper presents an extensive literature review of the current status of EVs and allied interface technology with the power grid. The main findings and statistical details are drawn from up-to-date publications highlighting the latest technological advancements, limitations, and potential future market development. The authors believe that electric vehicle technology will bring huge technological innovation to the energy market where the vehicle will serve both as a means of transport and a dynamic energy vector interfacing with the grid (V2G), buildings (V2B), and others (V2X)

Solid–Gas Thermochemical Energy Storage Materials and Reactors for Low to High-Temperature Applications: A Concise Review

Thermochemical energy storage materials and reactors have been reviewed for a range of temperature applications. For low-temperature applications, magnesium chloride is found to be a suitable candidate at temperatures up to 100 °C, whereas calcium hydroxide is identified to be appropriate for medium-temperature storage applications, ranging from 400 °C up to 650 °C. For the high-temperature range (750–1050 °C), oxides of cobalt, manganese, and copper are found to have the redox behaviour required for thermochemical heat storage. However, some of these materials suffer from low thermal conductivities, agglomeration, and low cyclability and, therefore, require further improvements. The concept of enhancing thermal conductivities through additives such as nanomaterials has been encouraging. From an operational point of view, fluidized-bed reactors perform better than fixed- and moving-bed reactors due to better particle interactions. There is, however, a need for the reaction bed to be further developed toward achieving optimum heat and mass transfers. Agitated fluidized-bed reactors have shown encouraging results and are suggested for further exploration. A combination of appropriate computational tools can facilitate an in-depth understanding of bed dynamics

Design and performance analysis of a regenerative evaporative cooler for cooling of buildings in arid climates

Evaporative cooling has been considered a low energy consumption process that often is associated with displacement ventilation and passive cooling strategies of buildings. While significant energy savings can be accrued from using evaporative cooling, there are many design challenges to improve the processes of heat and mass transfer and reduce design complexities. This paper seeks to advance the design of evaporative cooling through building and testing a novel regenerative evaporative cooler prototype. It proposes a design that integrates heat pipe and porous ceramic tube modules as an alternative to plate heat exchangers. The paper describes design arrangement of the cooler, a mathematical model and laboratory test results. Under controlled laboratory test conditions, the measured performance indices of wet bulb effectiveness, specific cooling capacity and coefficient of performance (COP) were determined as 0.8, 140 W per m2 of wet ceramic surface area and 11.43 respectively. Furthermore, experimental results show that under typical ambient conditions commensurate with that prevailing in arid climates, the cooler air supply temperature was as much as 14 oC below that of the ambient air

A Control Methodology for Building Energy Management Systems (BEMS) in Heat Networks with Distributed Generation

Reducing building energy consumption is important to achieve sustainable development, as a result, there is a need to investigate better energy systems with well-designed management infrastructure. At the Creative Energy Homes, a low-temperature heat network with distributed generation links seven properties. The aim of the system is to investigate the efficiency benefits of low-temperature heating, while at the same time testing the prosumer concept. For homeowners to be prosumers, they can buy and sell heat to a network. This system is the first of its kind, and as a result required bespoke Building Energy Management Systems (BEMS). This paper focuses on the hardware, software, and system operation used as part of project SCENIC (Smart Controlled Energy Networks Integrated in Communities). The project utilises a simple and cheap hardware configuration involving relays, IO boards and RaspberryPi microcomputers. An open-source Building energy Management System (oBeMS) platform is used for monitoring and control