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A thermosyphon solar water heating system with in‐tank auxiliary electric heater has been simulated according Malaysian hot water consumption profile using TRNSYS simulation program. The optimum value of a parameter is defined as the value which maximized the annual solar fraction of the system. This paper has a good deal of information concerning sizing of common components of thermosyphon solar water heater operated under certain condition (load volume, distribution profile and temperature). The results indicate that collector should be tilted at Ø + (→ 7° 37°) for all collector areas. Vertical storage tank has better performance in tropical climate (The average annual solar fraction for vertical was 88% and for horizontal was 82.9%).

This paper aims to compute demand, consumption and other avoidance saving by replacing existing geysers with split and integrated type air source heat pump (ASHP) water heaters, to prove the potential of both ASHP water heaters in both winter and summer by virtue of their coefficient of performance (COP) during the vapour compression refrigeration cycles and to demonstrate that despite the viability of both split and integrated ASHP system, the latter exhibits a better performance in terms of its COP and achievable savings and load factor.

This research emphasised the use of the data acquisition system housing various temperature sensors, power metres, flow metre, ambient temperature and relative humidity sensor to determine electrical energy consumption and useful thermal energy gained by the hot water in a geyser and storage tanks of residential ASHP water heaters. The load factors, average power and electrical energy consumptions for the 150 L high-pressure geyser, a 150 L split and integrated type ASHP water heaters were evaluated based on the controlled volume (150, 50 and 100 L) of daily hot water drawn off.

The results depicted that the average electrical energy consumed and load factors of the summer months for the geyser, split and integrated type ASHP water heaters were 312.3, 111.7 and 121.1 kWh and 17.9, 10.2 and 16.7 per cent, respectively. Finally, the simple payback period for both the split and integrated type ASHP water heaters were determined to be 3.9 and 5.2 years, respectively. By the application of the Eskom’s projected tariff hikes over the years, the payback periods for the split and integrated ASHP water heaters could be reduced to 3.3 and 4.1 years, respectively.

The experiments were conducted in a controlled outdoor research facility as it was going to be of great challenge in conducting both experiments simultaneously in a specific home. The category of the different types of ASHP water heaters was limited to one due to the cost implication. The experiment was also conducted at a single location, which is not a full representation of all the ambient conditions of the different regions of South Africa.

The experiments were done with a specific controlled volume of hot water drawn off from each of the three hot water heating devices. The experiments was structuring controlled to a specific volume of hot water drawn off and at specific period of the day and hence to not cater for random drawers and intermittent drawn off.

The findings help to assure homeowners that irrespective of the type of ASHP water heaters installed in their residence, they can be guarantee of year-round performance and a favourable payback period provided their hot water consumption is over 200 L per day. Also, although the split type ASHP water heater performed better than the integrated system the cost of installation and maintenance will be higher in a split type in comparison to the integrated type. Finally, by successful implementation of either of the ASHP water heaters the home owner can substantially save of his hot water bill.

The experimental design and methodology is the first of its kind to be conducted in South Africa. The results and interpretation were obtained from original data collected from the set of experiments conducted. Also, the authors are able to show that the introduction of back up element in an ASHP unit to run simultaneously with the vapour compression refrigeration cycles of the ASHP can reduce the COP of the overall system.

This paper aims to show that by using air source heat pump (ASHP) water heater in the residential sector, the energy consumption from sanitary hot water production can be reduced by more than 50 per cent. Hence, this study quantitatively and qualitatively confirms that domestic ASHP water heater is a renewable and energy efficient device for sanitary hot water production.

Design and building of a data acquisition system comprises a data logger, power meters, flow meters, temperature sensors, ambient and relative humidity sensor and an electronic input pulse adapter to monitor the ASHP water heater performance. All the sensors are accommodated by the U30-NRC data logger. The temperature sensors are installed on the inlet pipe containing a flow meter and the outlet pipe of the ASHP unit, the vicinity of both evaporator and expel cold air. An additional temperature sensor and a flow meter that cater for hot water drawn off measurements are incorporated into the data acquisition system (DAS).

The result from a specific monitoring split type ASHP water heater gives an average daily coefficient of performance (COP) of 2.36 and the total electrical energy of 4.15 kWh, and volume of hot water drawn off was 273 L. These results were influenced by ambient temperature and relative humidity.

The cost involved in purchasing the entire sensors and data logger limits the number and categories of ASHP water heaters whose performance were going to be monitored. Pressure sensors were excluded in the data acquisition system.

The data acquisition system can easily be designed and the logger can also be easily programed. Hence, no high technical or computer skills are needed to install the DAS and to be able to read out the results.

Hence, the data acquisition system can be installed on the entire domestic Eskom roll out air source heat pump water heaters to effectively determine the coefficient of performance and demand reductions.

This DAS is the first of its kind to be built in South Africa to be used to determine the performance of an ASHP water heater with high accuracy and precision. DAS is also robust.

Describes a study to measure the quality of service provided by food‐poisoning surveillance agencies in England and Wales in terms of the requirements of a representative consumer ‐ the egg producing industry ‐ adopting “egg associated” outbreak investigation reports as the reference output. Defines and makes use of four primary performance indicators: accessibility of information; completeness of evidence supplied in food‐poisoning outbreak investigation reports as to the sources of infection in “egg‐associated” outbreaks; timeliness of information published; and utility of information and advice aimed at preventing or controlling food poisoning. Finds that quality expectations in each parameter measured are not met. Examines reasons why surveillance agencies have not delivered the quality demanded. Makes use of detailed case studies to illustrate inadequacies of current practice. Attributes failure to deliver “accessibility” to a lack of recognition on the status or nature of “consumers”, combined with a self‐maintenance motivation of the part of the surveillance agencies. Finds that failures to deliver “completeness” and “utility” may result from the same defects which give rise to the lack of “accessibility” in that, failing to recognize the consumers of a public service for what they are, the agencies feel no need to provide them with the data they require. The research indicates that self‐maintenance by scientific epidemiologists may introduce biases which when combined with a politically inspired need to transfer responsibility for food‐poisoning outbreaks, skew the conduct of investigations and their conclusions. Contends that this is compounded by serious and multiple inadequacies in the conduct of investigations, arising at least in part from the lack of training and relative inexperience of investigators, the whole conditioned by interdisciplinary rivalry between the professional groups staffing the different agencies. Finds that in addition failures to exploit or develop epidemiological technologies has affected the ability of investigators to resolve the uncertainties identified. Makes recommendations directed at improving the performance of the surveillance agencies which, if adopted will substantially enhance food poisoning control efforts.

Low flow bikini solar combisystems and high flow tank‐in‐tank solar combisystems have been studied theoretically. The aim of this paper is to study which of these two solar combisystem designs is suitable for different houses. The thermal performance of solar combisystems based on the two different heat storage types is compared.

The thermal performance of Low flow bikini solar combisystems and high flow tank‐in‐tank solar combisystems is calculated with the simulation program TRNSYS. Two different TRNSYS models based on measurements were developed and used.

Based on the calculations it is concluded that low flow solar combisystems based on bikini tanks are promising for low energy buildings, while solar combisystems based on tank‐in‐tank stores are attractive for the houses with medium heating demand and old houses with high heating demand.

Many different Solar Combisystem designs have been commercialized over the years. In the IEA‐SHC Task 26, twenty one solar combisystems have been described and analyzed. Maybe the mantle tank approach also for solar combisystems can be used with advantage? This might be possible if the solar heating system is based on a so‐called bikini tank. Therefore, the new developed solar combisystems based on bikini tanks is compared to the tank‐in‐tank solar combisystems to elucidate which one is suitable for three different houses with low energy heating demand, medium and high heating demand.

The purpose of this paper is to describe the effect of attitudes in promoting sustainable operations in hotels. The aim of this paper is to demonstrate the interaction between the users' behaviour and the way energy is consumed in Greek hotels in a long‐term period.

In total, two scenarios are developed, using the Long Range Energy Alternative Planning software (LEAP). Each scenario exhibits different findings proposing significant, but easy to apply alterations to hotels. The first one is the Business as Usual (BaU) scenario, and it is developed based on the current trends in energy use in hotels. The second is the Policy scenario, which is developed based on the existing legislative framework, Greek and EU. Through interviews with open‐ended questions, hoteliers' responses reveal their views and attitudes in energy initiatives, along with the level of information they have on the existing energy legislation – Greek and European – to reduce energy consumption in buildings.

This research project, aims at identifying the hoteliers' views in applying energy efficiency measures in their facilities. The BaU scenario displays the current energy consumption in hotels, without policy interventions. The Policy scenario displays the effectiveness of each proposed measure in all services offered in hotels. This analysis provides recommendations in order to improve the current energy framework.

This methodology provides the development of a model that combines the existing energy measures considering also the end‐users' behaviour. It shows the areas that need to change in order to reduce energy consumption in the whole population of Greek hotels. It is a process that could be applied easily in other countries, not only in Greece.

This paper is a generic research analysis. The data collection has been selected for the first time from the sample of hotels. This type of research has not been developed previously in Greek hotels, since attitudes, energy consumption and measures have not been combined previously, in order to promote sustainable operations in hotels.

In the Court of Appeal last summer, when Van Den Berghs and Jurgens Limited (belonging to the Unilever giant organization) sought a reversal of the decision of the trial judge that their television advertisements of Stork margarine did not contravene Reg. 9, Margarine Regulations, 1967—an action which their Lordships described as fierce but friendly—there were some piercing criticisms by the Court on the phrasing of the Regulations, which was described as “ridiculous”, “illogical” and as “absurdities”. They also remarked upon the fact that from 1971 to 1975, after the Regulations became operative, and seven years from the date they were made, no complaint from enforcement authorities and officers or the organizations normally consulted during the making of such regulations were made, until the Butter Information Council, protecting the interests of the dairy trade and dairy producers, suggested the long‐standing advertisements of Reg. 9. An example of how the interests of descriptions and uses of the word “butter” infringements of Reg. 9. An example af how the interests of enforcement, consumer protection, &c, are not identical with trade interests, who see in legislation, accepted by the first, as injuring sections of the trade. (There is no evidence that the Butter Information Council was one of the organizations consulted by the MAFF before making the Regulations.) The Independant Broadcasting Authority on receiving the Council's complaint and obtaining legal advice, banned plaintiffs' advertisements and suggested they seek a declaration that the said advertisements did not infringe the Regulations. This they did and were refused such a declaration by the trial judge in the Chancery Division, whereupon they went to the Court of Appeal, and it was here, in the course of a very thorough and searching examination of the question and, in particular, the Margarine Regulations, that His Appellate Lordship made use of the critical phrases we have quoted.

This paper aims to propose an energy efficiency plan (with technical and behavioural improvement measures) for a Portuguese higher education building – the Teaching Building of the Faculty of Economics of the University of Coimbra (FEUC).

The study was developed in the context of both the “Green Campus – Challenge for Energy Efficiency in Higher Education” and the Energy for Sustainability Initiative of the University of Coimbra, Portugal. An energy audit was conducted based on the analysis of the energy consumption profiles. A monitoring campaign was carried out to measure and disaggregate the electricity consumption. The consumption of natural gas and water were also assessed. The building envelope and the heating and lighting systems were also evaluated. Some patterns of energy-environmental behaviours of the academic community were investigated through a Web-based survey.

The energy efficiency plan contemplates short-term tangible/intangible actions. It also considers the investment and payback period of the tangible measures. The implementation of three improvement measures in the lighting system would lead to a consumption reduction of about 26,123 kWh/year, avoiding the emission of 3,704 KgCO2/year, for an initial cost of 9,920 (payback period of 3.7 years).

Results are restricted to the case study and there are limitations in their generalisation outside of their context. However, they show some broadly implications and trends that have relevance for the higher education sector. This paper highlights the importance of engaging students, faculty and technical staff for working together on the assessment of the energy efficiency of the buildings where they study and work.

The higher education sector holds important functions in educating the next generation of professionals for a sustainable culture. The categories of activities described in this paper are good examples of what can be done within the academic community for acting towards sustainability. The results also pointed out that making users aware of their energy consumption is a priority towards the energy efficiency in higher education buildings.

Reductions on energy consumption are expected if the energy efficiency plan would be implemented. The results of the behavioural study were presented to the FEUC’s board of directors to be integrated in the “Good Practices Manual on Water and Energy Management”.

This article aims to optimise energy use and consumption by integrating Lean Six Sigma methodology with the ISO 50001 energy management system standard in an Irish dairy plant operation.

This work utilised Lean Six Sigma methodology to identify methods to measure and optimise energy consumption. The authors use a single descriptive case study in an Irish dairy as the methodology to explain how DMAIC was applied to reduce energy consumption.

The replacement of heavy oil with liquid natural gas in combination with the new design of steam boilers led to a CO₂ footprint reduction of almost 50%.

A further longitudinal study would be useful to measure and monitor the energy management system progress and carry out more case studies on LSS integration with energy management systems across the dairy industry.

The novelty of this study is the application of LSS in the dairy sector as an enabler of a greater energy-efficient facility, as well as the testing of the DMAIC approach to meet a key objective for ISO 50001 accreditation.