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Decreasing energy demand due to improved building standards requires the development of new biomass combustion technologies to be able to provide individual biomass heating solutions. The purpose of this paper is, therefore, the development of a pellet water heating stove with minimal emission at high thermal efficiency.

The single components of a 10 kW water heating pellet stove are analysed and partly redesigned considering the latest scientific findings and experimental know‐how in combustion engineering. The outcome of this development is a 12 kW prototype which is subsequently down‐scaled to a 6 kW prototype. Finally, the results of the development are evaluated by testing of an accredited institute.

Based on an existing pellet water heating stove, the total excess air ratio was reduced, a strict air staging was implemented and the fuel supply was homogenized. All three measures improved the operating performance regarding emissions and thermal efficiency. The evaluation of the development process showed that the CO emissions are reduced by over 90 per cent during full load and by 30‐60 per cent during minimum load conditions. Emissions of particulate matter are reduced by 70 per cent and the thermal efficiency increased to 95 per cent.

The result represents a new state of technology in this sector for minimal emissions and maximal thermal efficiency, which surpasses the directives of the Eco label “UZ37” in Austria and “Blauer Engel” in Germany, which are amongst the most stringent performance requirements in the European Union. Hence this design possesses a high potential as heating solution for low and passive energy houses.

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 look more closely at incentives for a landlord to use individual metering and charging of heat and water. This paper also aims to look at the possible reasons for the differences in use of individual metering and charging between Sweden and Germany.

The research in this paper is based on a questionnaire and interviews with landlords, in Sweden, using individual metering and charging.

The two main incentives for the landlords in the survey to use individual metering are the possibility to save energy and the possibility to create a fair allocation of heating cost between tenants. Sweden has a long history of heat and water included in the rent leading to a possibly tougher transition to individual metering.

To see the overall picture and understand the purpose of individual metering is important to avoid conflicts between landlords and tenants. The paper aids this process.

This paper aims to describe the nature and significance of Sorel’s cooking appliance and to examine the promotion and marketing options used by Sorel to make it an appliance that was “widely used in private residences and by small eating houses.” It will highlight the role of the individual and will demonstrate that marketing and promotion strategies that are modulated by the social ambitions of the manufacturer.

The basis of this research is extensive quantitative and qualitative analysis of primary sources, mainly the advertisements placed by Sorel, supported by information in contemporary newspapers and journals.

Stanislas Sorel’s invention of an early form of thermostat allowed him to develop a stove that could cook a four-course family dinner largely unsupervised, an invention which was poised to revolutionise the lives of many households. Sorel was primarily an inventor striving for acceptance in the scientific world, with limited skills in the commercialisation of his inventions. His promotion and marketing efforts reflect both the social realities of the time and his own ambitions.

There has been very little research into the way small French inventors and manufacturers approached the marketing of their products. The paper provides a unique insight into the promotion techniques of a mid-nineteenth-century French inventor-cum-entrepreneur and highlights the role of the individual and how actions are constrained by ambition and opportunity. The paper provides an example of how research into how specific individuals can inform the larger history of marketing.

We are growing accustomed to shock tactics of the US Administration in dealing with toxic residues in food or additives which are a hazard to man, as well as the daily press infusing sensation, even melodrama, into them, but the recent action of the FDA in calling in from the food market several million cans of tuna and other deep sea fish because of the presence of mercury has had the worthwhile effect of drawing world attention to the growing menace of environmental pollution. The level of mercury in the fish is immaterial; it should never have been there at all, but it stresses the importance of the food chain in the danger to man and animal life generally, including fish beneath the sea. Without underestimating risks of pollution in the atmosphere from nuclear fission products, from particulate matter carried in the air by inhalation or even skin absorption, food and drink, which includes aqua naturale would seem to be the greatest danger to life. What these recent events illustrate in a dramatic manner, however, is the extent of pollution.

Stress corrosion cracking at the weld areas in the interior of blast furnace stoves has become a world wide problem which has been accentuated by the higher operating temperatures and pressures now used. This paper describes the work carried out to evaluate various protective coatings proposed for application to the interior of the stove shell plates to prevent the stress corrosion. A heat and chemical resistant polyurethane primer‐pitch polyurethane top coat has given superior results to all coatings tested, particularly when applied over a hot sprayed ceramic.

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 present a systematic scoping review of the influences of some situational factors on the energy consumption behaviour of households. Household’s energy choice and manner of utilization define its energy consumption behaviour; it is a key factor in determining the energy efficiency of households. Despite the energy-efficient technological innovations and awareness on environmental/health implications of using certain energy sources and technologies, households still use inefficient, traditional energy sources and technologies. Some researchers have attempted to use economic and psychological theories to explain the situation with the hope of achieving a change in behaviour towards sustainable energy utilization but to no avail. This is because the theories fail to consider situations beyond individuals or households. A clear understanding of situational factors and how they influence household energy behaviour will provide information that will aid deeper research and policy formulation towards sustainable energy behaviour of households.

A scoping systematic review of available literature regarding real-life cases in both developed and developing countries was carried out to determine the possibility of situational factors affecting household energy choices and utilization.

The result of the review showed that situational factors have a significant influence on household’s energy consumption. The main policy implications observed are the need for laws that will encourage energy-saving renovations in houses, make compulsory the provision of recreational facilities in residential areas to reduce in-home energy consumption. The need for increased access to electricity and other efficient energy sources and cooking technologies has also been observed. Intensive awareness campaigns are required to disabuse the minds of people about cultural issues that mitigate improved cook stove adoption.

The paper provides information on the influence of some of the factors, which affect energy consumption in households, which fluctuate depending on the current situation of the consumer and are time-bound (situational factors). The information will help policymakers and regulators to understand the influence of situational factors on household energy consumption, thereby enabling them to make policies that will enhance sustainable energy consumption.

Corrosion failures due to condensing flue gases containing H₂O, SO₃, NO_x and HCl still occur more often than might be expected. The corrosion failures can be of several types: general corrosion, pitting attack and stress corrosion cracking (SCC). The chemistry of condensing gases is discussed, and some examples of corrosion in large‐scale installations are presented, including blast stoves for steel production, heat recovery steam generators, and waste incineration boilers. The use of thermal insulation inside boiler casings can result in nitrate SCC when the flue gas contains high concentrations of NO_x. Nitric acid from flue gas can react with carbon steel and insulation material forming ammonium nitrate and calcium nitrate. Both materials have hygroscopic properties and are very corrosive, even above the water dewpoint of the gases.

The Secretary of State in exercise of powers conferred by sections 139(1) and 180(3) of the Factories Act 1961 and now vested in him and of all other powers enabling him in that behalf, hereby makes the following Order:—