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Life Cycle Assessment (LCA) is an effective methodology to assess the energy and environmental impacts of energy systems during their life cycle, including manufacturing, operation and end-of-life. The aim of the paper is the application of a simplified LCA tool, developed in the framework of the International Energy Agency Solar Heating and Cooling Task 48, for comparing different typologies of solar assisted heating and cooling systems. In detail, solar thermal heating and cooling systems located in Palermo (southern Italy) and in Zurich (Switzerland) were compared with conventional systems assisted by grid connected and stand-alone photovoltaic plants. A validation of the tool was also carried out by comparing the obtained results with those of in-depth LCA studies. The results showed that the best system configuration in Palermo is the conventional system assisted by a grid-connected photovoltaic plant. Its impact on global energy requirement is about 83.7% and 74.5% of the corresponding impact of the solar thermal heating and cooling and the conventional system assisted by a stand-alone photovoltaic system, respectively. Different considerations can be made for Zurich, where the solar heating and cooling system performs better than the others; it is characterized by a global energy requirement that is 85.3% and 81.2% of the grid-connected and stand-alone photovoltaic assisted conventional systems, respectively. A similar trend is traceable for the global warming potential indicator. The validation of the LCA tool proved it to be reliable since deviations with a detailed LCA of the same system are contained below a 5% difference in all the comparable systems.

The solar heating and cooling systems are among the best solutions for the current energy and environment issues. In this chapter, the background and overview of the solar heating and cooling systems are given. In these systems, the energy sources are the solar power, and the consuming components include the heating and cooling devices. In order to ensure the steady operation of solar driven systems, the heat storage systems are also necessary. In this case, the different choices of solar energy, solar heating, solar cooling and heat storage are briefly introduced in this chapter. A technology roadmap is given at last which provides a clear connection between these introduced technologies.

This chapter discusses the aspects that should be considered when selecting the latent heat storage for a specific solar heating and cooling application. It positions latent heat storage in relation to solar heating and cooling systems helping determine the storage size and the temperature level. It quantifies temperature losses and indicates how the major sources of irreversibilities can be quantified. It shows how the savings related to energetic performance can be determined. It distinguishes between stationary phase change materials (PCMs) and pumpable slurries of PCMs, and it illustrates the advantages of pumpable PCM slurries. Finally, a method is proposed to estimate the performance of different storage/heat exchanger concepts and a procedure for the selection of a latent heat storage type is proposed.

Advanced energy storage is an essential key technology for adjusting the time discrepancy and instability between solar energy supply and energy demand in solar heating and cooling systems. Among the various energy storage technologies, the thermochemical energy storage method has received more attention because of its distinct advantages of higher energy storage density and low heat loss compared with the conventional sensible and latent energy storage methods. The development of thermochemical energy storage technology is reviewed in this chapter. A lot of theoretical and experimental studies on reactants, chemical reaction kinetics, and system designs are introduced and analyzed, and the future development of thermochemical heat storage is discussed.

A solar tracker can keep the collector’s aperture perpendicular to the incident light to maximize the solar radiation, so it is a key component to improve the performance of solar collector. In this chapter, the composition and types of solar tracking are summarized, and the applications of various technologies are demonstrated respectively.

Renewable energy sources compete with conventional fuels in three distinct markets: hot water and space heating, power generation, and transport fuels. Hot water for sanitary uses as well as space heating for millions of buildings is supplied by systems that employ solar energy. In this chapter, a brief overview of the global solar thermal market is presented. Furthermore, the main solar thermal technologies for heating and cooling are presented, as well as methods that can be used to estimate the environmental impact of various technologies and systems and their implementation on solar technologies.

In the coming years, it is anticipated that if we continue with the same pace of energy consumption, communities will continue to face three major challenges; a mounting increase in energy demands, pollution, and global warming. On a local scale, Egypt is experiencing one of its most serious energy crises in decades. The energy consumed in indoor cooling and heating is the biggest portion of total energy consumption in residential buildings. This paper is an experimental simulation study for building retrofitting in off-grid settlements in semi-arid climates, using Trombe wall as a low-tech passive heating and cooling solution. In this study, we made developments to the conventional classic Trombe wall using occupant-centered design and living lab experimental methods. The thermal efficiency of the proposed Trombe wall design is simulated during winter and summer peaks. In the proposed design we used gray paint instead of typical black paint in addition to 15 cm reversible natural wool insulation and two 3 mm thick roll-up wool curtains. The new design reduced the heating load by 94% and reduced the cooling load by 73% compared to the base case with an annual energy savings of 53,631 kW h and a reduction in CO2 emissions of 144,267 kg of CO2. The living lab test proved that the proposed design of the Trombe wall is economically viable and the payback time is 7 months. It is recommended that the proposed design be monitored for a whole year to have an accurate assessment of its efficiency. A post occupancy evaluation is also needed to measure local residents’ acceptance and perceived comfort after retrofitting.

The national demonstration program for the solar heating and cooling of commercial and residential buildings consists of a series of demonstration projects sponsored in whole or in part by the United States Department of Energy (DOE). The solar energy systems used in the demonstration projects include a wide range of designs and a variety of applications in various climatic regions. This paper describes the national demonstration program, including its objectives, history, and current status. The performance of solar energy systems in the demonstration program is also reviewed.

The widespread utilization of solar heating and cooling of buildings has positive and negative impacts on the planning and cost of production of electric power systems. The positive impact is that of favorable improvements in annual and seasonal load factors. The negative impact is that of unfavorable effects on daily load factors. By means of adequate system design and control strategies the daily effect can be turned around into an advantage. The result is an overall positive impact on the planning and operation of power systems. The paper discusses methodologies and techniques for peak shaving of electrical demand by adequately designed solar systems. It also formulates the generation planning problem in the presence of solar heating and cooling systems.

Task III of the International Energy Agency's Solar Heating and Cooling Programme has recently completed a range of studies on the durability and reliability of solar collectors. Two specific topics treated by the Task are material degradation in solar collectors and qualification tests for whole collector modules. A survey of this work is given.

One of the major fields of interest in Task III of the International Energy Agency's Solar Heating and Cooling Programme has been the development of means to evaluate solar domestic hot water (SDHW) systems using short-term test methods. Within the participating countries of Task III many different approaches to SDHW system testing have been developed in recent years. A review of these methods showed their suitability to different conditions and requirements and suggested desirable features for test methods for common use. Drawing on this experience, the Task has adopted a three-fold approach to the development of SDHW system tests: long-term performance prediction based on test measurements of component parameters, long-term performance prediction based on correlations with test measurements on the whole system, and diagnostic inspection procedures for the system configuration and the performance of the sensors and controllers. A summary of progress in this work is presented.

A solar heating and cooling system delivering part of the thermal energy needs of an industrial plant has been designed. Moderately concentrating parabolic trough collectors of 2000 m2 active area will produce hot water for heating, cooling and hot water production. A 150 ton standard type absorption water chiller is used for cooling during summer time.

The performance of a combined solar heating and cooling system was studied for Mediterranean climatic conditions, using a detailed computer model and hourly weather data. The TRNSYS-CODE was used to model the solar system and the building. The weather data used are from Athens. A reference year based on long term averages was developed. The system consists of flat plate collectors, a LiBr/H 2 O floor area of 540 m 2 . Also the performance of evacuated tube collectors was studied for such systems. The results of the simulation show that high yearly useful collector output (more than 500 KwH/M 2 ) is possible with flat plate collectors. With evacuated tube collectors about 40% more. A rough economic analysis shows that one can expect fuel savings of about 19 USD/m 2 for flat plate collectors, with a solar fraction of 80%.

This paper takes a cautious view of solar thermal energy use as a reasonable alternative to fossil fuels for heating and cooling of buildings. The paper emphasizes two problems. One is the relationship between solar thermal heating and cooling of buildings and electric utility rates. The other is the social and private opportunity costs of solar thermal heating for single-family residences. The paper draws on NSF-funded research on the incentives and barriers to commercial adoption of solar heating and cooling of buildings.

Glass is an essential component of virtually all solar heating and cooling systems and so its properties, its strengths and its limitations should be thoroughly understood by the designers of such systems. Recent advances in glass technology offer those designers new capabilities in dealing with the admission of solar heat and light into spaces where they are needed and in rejecting both heat and light when cooling and darkness are required.

This paper is a report on the analyses and evaluation of collectors used in the national demonstration program for solar heating and cooling of non-residential buildings. The characteristics and performance of 17 solar collectors used in 32 representative demonstration projects are presented. The collectors are compared in cost, design, and thermal performance, and the advantages of each type of collector noted. An evaluation of physical characteristics such as absorber materials, heat transfer fluids, types of insulation, cover plate materials, and collector perimeter design is also presented.

The thermal performance of solar collectors measured according to standard test methods is appropriate for only a narrow range of operational and environmental conditions. It is usually assumed that the test results are fully characterized by the familiar Hottel-Whillier-Bliss equation, but this relationship was developed for flat plate collectors and is inadequate for representing a large number of the collectors currently being produced. In many cases the performance determined by the test may differ from that obtained in actual operational conditions. The work of Task III on the characterization of collector performance is aimed towards evaluating the effect of atmospheric factors (irradiance level, ambient temperature, windspeed) and of operational conditions (collector mass flowrate, tilt) on the thermal performance of a variety of solar collectors. Its objective is the development of improved test procedures and performance representations that account for these effects.

Publisher Summary This chapter discusses the use of solar energy in heating and cooling. Solar energy for heating and cooling has the advantages of a large resource base and widespread distribution. Its disadvantages are that it is spread rather thinly and thus must be collected over relatively large areas, and is erratic, fluctuating day to night and with weather conditions. Solar energy is a “free” fuel, but since it requires such a large collection area it often requires a large capital investment to make use of it. Solar energy is the only large resource among the renewable fuels and will steadily become more important as the technology of collection, storage, and use advances, and as other sources of heat become more scarce and expensive. There is no pollution to discharge. In a heavily solar-dependent urban area there may develop problems over solar access, shading, etc., as well as aesthetic consequences. The major environmental impact is apt to be indirect. A lot of conventional energy with its associated environmental impact will be required if a nation were to undertake the manufacture of a large number of active solar systems.

The integration of renewable energy sources (geothermal, biomass, and solar) and desalination systems into novel polygeneration plants is investigated. Two main arrangements are considered: geothermal (GP) and biomass (BP) polygeneration. Both systems include concentrating photovoltaic/thermal solar collectors, a multieffect distillation system for seawater desalination, a single-effect LiBr-H2O absorption chiller, storage tanks, heat exchangers, balance-of-plant devices; a biomass auxiliary heater and geothermal wells are also included, in BP and GP, respectively. The systems can provide electricity and hot water, used for space heating, cooling, domestic hot water production, and drinkable desalted water. Both systems are simulated by means of a zero-dimensional dynamical simulation model. Thermoeconomic, exergy, and exergoeconomic analyses are also presented, aiming at defining the best values of the main design variables. Two case studies are discussed: city of Naples (BP) and Pantelleria island (GP), both characterized by solar and geothermal resources and scarcity of fossil fuels and freshwater.