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The proposed solar thermal cooling cogeneration cycle is well suited for industrial as well as domestic needs and it eliminates need of electricity for refrigeration system. The purpose of this paper is to integrate power and cooling to minimize the energy usage.

The proposed plant has double turbine with superheater and reheater to extract more energy, operating on single generator. The saturated refrigerant from the exit of the generator is used to run the primary turbine and the exit mass of refrigerant is split into 50:50 cooling to power ratio.

It produces additional power of 24 kW at absorber concentration of 0.42 and turbine inlet concentration of 0.95, with separator temperature of 145°C and atmosphere temperature of 30°C.

The proposed cooling cogeneration cycle is possible to run on all the refrigerant working fluid mixture and it overcomes the problem of Goswami cycle which is not possible to run in hot climatic countries.

The cycle can operate individually as refrigeration cycle, power cycle and both and it will run all climatic conditions.

An effective chemical conditioning technique was successfully tested and investigated to control and minimize the chemistry-related damages within mixed metallurgy steam and water cycle of Heller dry cooled combined cycle power plants (CCPPs), in which cooling water and condensate are completely mixed in direct contact condenser. This study aims to perform a comprehensive experimental research in four mixed metallurgy steam and water cycle.

A comprehensive experimental study was carried out in four mixed metallurgy steam and water cycle fabricated with ferrous- and aluminum-based alloys which have various corrosion resistance capabilities in contact with water. Chemical conditioning was conducted using both volatile and non-volatile alkalizing agents, and, to perform chemical conditioning effectively, quality parameters (pH, conductivity, dissolved oxygen, sodium, silica, iron, aluminum and phosphate) were monitored by analyzing grab and online samples taken at eight key sampling points.

Results indicated that pH was the most critical parameter which was not mainly within the recommended ranges of widely used standards and guidelines at all key sampling points that generally increases the occurrence of chemistry-related damages. The other quality parameters were mostly satisfactory.

In this research, the development of a suitable chemical conditioning technique in mixed metallurgy steam and water cycle, fabricated with ferrous and aluminum-based alloys, was studied. The obtained results in this thorough research work was evaluated by comparison with the chemistry limits of the widely used standards and guidelines, and combined use of volatile and solid alkalizing agents was considered as a promising chemical conditioning technique for utilization in mixed metallurgy units of Heller dry cooled CCPPs.

The objective of this study is to highlight the questions arising in the design of district heating and cooling systems (DHCSs) in a distributed generation context and to present a model to help find cost‐effective solutions.

Literature on energy systems optimisation is reviewed and a mixed integer programming model for decentralized DHCSs design is developed and applied to two real case studies.

Distributed cooling generation partly coupled with distributed cogeneration and DH is the preferred solution in the examined areas. The optimal configurations, with special reference to network sizing and layout, significantly depend on heating demand profiles and energy prices.

Interdependencies between energy units sizing and network layout definition should be considered. Obtaining more robust and reliable network configurations should be the objective of future modelling efforts.

Despite the growth of distributed energy conversion, designers often rely on centralized concepts in order to reap economies of scale. The presented model helps in discovering less usual solutions representing the most profitable option.

Combining and comparing central and distributed production of heat and cooling under consideration of network costs.

THE combined effect of Sections III and IV is a gain of up to 3 per cent t.h.p. at moderate speeds, over the best systems without a blower, in spite of the detrimental effect of heating of the air due to compression. The blower absorbs about 10 per cent b.h.p. which is additionally recovered as useful thrust. Pressure air cooling does not permit the economical use of materially smaller matrices.

THE trend of design in the modern aeroplane has been toward improved performance realised through external cleanness. It is apparent that the number of essential units comprising a modern aeroplane is nearly a minimum at the present stage of the art, and it appears also that the possibilities of further striking reductions in the drag of these units, due to change in form or shape either individually or in combination, are not great.

The aim of this study is to analyze future changes of freshwater needs in the electricity production sector and to identify hotspots where future cooling water needs may not be fulfilled.

To address the goals of this study, a scenario and simulation approach was selected to estimate water availability and water uses in Europe up to 2050. Two SCENES scenarios were selected to cover a wide range of water‐related driving forces including future developments in population, GDP, electricity production, technological and structural changes, as well as climate change.

Depending on the scenario, water withdrawals in the electricity production would increase by 68 percent or decrease by 33 percent between 2000 and 2050. At the same time, water availability at low flow (Q90) would decrease because of climate change in southern and south‐eastern parts of Europe as well as in Ireland and the UK. Especially in these regions hotspots were identified where water is scarce and where growing water demand promotes water stress that may cause economic losses.

This paper presents hotspots of the thermal electricity production sector in Europe. In these regions water shortages were expected to lead to water stress due to climate change accompanied by increasing water demand for cooling purposes and by competing water use sectors.

ALTITUDE supercharging of aeroplane engines by means of turbo‐blowers driven by exhaust‐gas turbines differs from ordinary charging of internal combustion engines because the process is much more accentuated. Whilst the output of stationary engines can be increased by 50 per cent, that of rail‐car engines by 80 per cent, by supercharging, an aeroplane engine, to give its full output at 12,000 m. altitude, has to be supercharged so as to give four times its output without supercharging. Thus altitude supercharging offers certain peculiarities.

Natural gas (NG) consumption is increasing at an alarming rate, and more than 50 percent of this gas is used in generating electric power (EP) and desalted seawater (DW) in what is called cogeneration power desalting plants (CPDP). In this context, the purpose of this paper is to study the energy status in Qatar. More specifically, Qatar energy supply side is studied through the CPDP. In an effort to decrease the energy consumption by raising the efficiency of the CPDP (at the supply side), and conserving energy at the demand side, primarily energy footprint is performed.

The status of CPDP, in terms of the type, capacity, fuel consumption is studied, and measures that should be taken to improve their performance and reduce their consumed fuel are presented.

Study of the EP and DW sector showed that the fuel consumed in the CPDP can be reduced substantially by converting the simple gas turbine cycle to combined cycle to raise its efficiency from 30 percent to up to 50 percent. On the demand side, it was shown that air conditioning (AC) of buildings consumes about two‐third of the summer peak load; and about half of the annual EP output. So, measures to decrease the AC cooling load are suggested by implementing building code to decrease the consumed energy in buildings.

Data on the NG and oil proven reserve, production, and consumption are limited and scattered. It is necessary to have a clear picture of Qatar showing the flow of energy supply, demand, consumption, and losses in certain sectors to know where energy can be conserved; and this paper is the first trial in that direction. Although prime energy looks abundant today, it can be consumed locally within few decades if consumption is not controlled.

The purpose of this paper is to target on designing a short-term load prediction framework that can accurately predict the cooling load of office buildings.

A feature selection scheme and stacking ensemble model to fulfill cooling load prediction task was proposed. Firstly, the abnormal data were identified by the data density estimation algorithm. Secondly, the crucial input features were clarified from three aspects (i.e. historical load information, time information and meteorological information). Thirdly, the stacking ensemble model combined long short-term memory network and light gradient boosting machine was utilized to predict the cooling load. Finally, the proposed framework performances by predicting cooling load of office buildings were verified with indicators.

The identified input features can improve the prediction performance. The prediction accuracy of the proposed model is preferable to the existing ones. The stacking ensemble model is robust to weather forecasting errors.

The stacking ensemble model was used to fulfill cooling load prediction task which can overcome the shortcomings of deep learning models. The input features of the model, which are less focused on in most studies, are taken as an important step in this paper.

This study has covered many types of solar-powered air-conditioning systems that may be used as an alternative to traditional electrically powered air-conditioning systems in order to reduce energy usage. Solar adsorption air cooling is a great alternative to traditional vapor compression air-conditioning. Solar adsorption has several advantages over traditional vapor-compression systems, including being a green cooling technology which uses solar energy to drive the cycle, using pure water as an eco-friendly HFC-free refrigerant, and being mechanically simple with only the magnetic valves as moving parts. Several advancements and breakthroughs have been developed in the area of solar adsorption air-conditioners during the previous decade. However, further study is required before this technology can be put into practise. As a result, this book chapter highlights current research that adds to the understanding of solar adsorption air-conditioning technologies, with a focus on practical research. These systems have the potential to become the next iteration of air-conditioning systems, with the benefit of lowering energy usage while using plentiful solar energy supplies to supply the cooling demand.