1. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria SOLAR DESIGN Applied Climatology (ARC 810) Department of Architecture Federal University of Technology, Akure, Nigeria

2. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria OUTLINE  Introduction  Basic Concepts of Solar Design  Conversion of Solar Energy  Solar Collectors  Uses of Solar Energy  Solar Heating Systems  Solar Cooling Systems  Design of Solar Buildings

3. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  INTRODUCTION Solar energy is converted for use in buildings in three ways:  Biochemical Conversion,  Electrical Conversion, and  Thermal Conversion. Solar energy collecting devices include:  Flat Plate Collectors,  Concentrating or Focusing Collectors, and  Photovoltaic collectors.

4. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  INTRODUCTION Solar energy is used for:  Space Heating and Cooling,  Water Heating,  Cooking and Drying,  Distillation,  Expansion and Steam Engines, and  Electricity Generation.

5. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  INTRODUCTION There are active and passive solar heating systems. Passive heating systems include:  Direct Gain Systems,  Thermal Storage Walls,  Sun Spaces,  Thermosiphon Systems, and  Mixed Systems.

6. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  INTRODUCTION There are also solar cooling systems. Natural cooling systems utilize radiant night cooling, specialized radiators, convective and evaporative cooling, roof ponds, earth cooling and comfort ventilation.

7. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  INTRODUCTION The design of solar buildings involves:  Data Collection,  Bioclimatic Analysis,  Solar Analysis,  Thermal Analysis,  Choice of Appropriate System, and  Integration.

8. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  BASIC CONCEPTS OF SOLAR DESIGN The sun is the main source of energy on earth, producing free energy, practically endlessly. This energy can be harnessed to provide most of building energy requirements at little cost. The main obstacles were knowledge, cost and technology. The technology is now much more reliable, prices have fallen considerably and there is better awareness of solar issues.

9. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  CONVERSION OF SOLAR ENERGY  Biochemical conversion involves photo-biochemical processes such as Photosynthesis.  Electrical conversion using thermoelectric or photovoltaic processes.  Thermal conversion to heat energy.

10. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COLLECTORS The flat plate collector is made up of an absorber plate of black metal backed with insulation and a glass or plastic cover.

11. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COLLECTORS Concentrating or focusing collectors use various devices for concentrating solar radiation on the surface of an absorber.

12. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COLLECTORS Photovoltaic collectors convert radiant energy directly into electrical energy using photovoltaic cells A photovoltaic cell

13. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  USES OF SOLAR ENERGY  Space heating through the use of collectors.  Space cooling through refrigeration.  Water heating using the thermosiphon principle.  Cooking using solar-driven cookers.  Drying of agricultural crops or products.

14. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  USES OF SOLAR ENERGY  Distillation of non-potable water for drinking.  Water pumping using solar-powered engines.  Electricity, through photovoltaic processes and solar- powered generators.

15. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR HEATING SYSTEMS In solar design of buildings solar heating systems are used to supply some of the energy needed both for space and domestic water heating. There are two types - passive and active.

16. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR HEATING SYSTEMS Passive solar heating systems include:  Direct gain system energy collected through windows and other glazing and stored within the building structure.  Thermal storage walls in the form of vented Trombe walls, unvented Trombe walls, and water walls.

17. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR HEATING SYSTEMS  Sun spaces, such as thermal storage roof systems.  Thermosiphon systems transport heat and mass by natural convection of a fluid such as air or water.  Mixed passive system (Combination of two or more systems).

18. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR HEATING SYSTEMS Passive Solar Systems

19. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR HEATING SYSTEMS Active solar heating systems are systems in which the flow of energy is forced by mechanical means. These systems are usually more complicated and more expensive than passive systems.

20. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COOLING SYSTEMS Solar cooling systems are used for cooling and ventilation of buildings. The first concern in solar cooling is how to avoid cooling loads. Minimizing heating reduces the problem of providing sufficient cooling. There are also passive and active cooling systems.

21. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COOLING SYSTEMS Passive (Natural) cooling systems include:  Radiant night cooling from longwave net heat loss (from roof mass) to the night sky.  Radiant cooling with specialized radiators.  Convective cooling using cool outdoor air.

22. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COOLING SYSTEMS  Evaporative cooling, through water evaporation.  Roof ponds, also through evaporation.  Earth cooling, using the earth as a heat sink.  Comfort ventilation, using ambient air for cooling.

23. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COOLING SYSTEMS Passive Solar Ventilation Systems

24. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COOLING SYSTEMS Passive Solar Cooling Systems

25. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  SOLAR COOLING SYSTEMS Active cooling systems are systems that use some mechanical means for cooling. They can be either open cycle or closed cycle.

26. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  DESIGN OF SOLAR BUILDINGS Designing solar buildings is a complex process. The architect should take maximum advantage of environmental conditions to enhance thermal comfort. However, in climates where this is not achievable - cooling or heating devices have to be installed.

27. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  DESIGN OF SOLAR BUILDINGS The following steps are usually involved in solar design: Data Collection. This involves the collection of climatic data for the specific site including outdoor air temperatures, humidity or vapour pressure, wind speed and direction, etc.

28. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  DESIGN OF SOLAR BUILDINGS Bioclimatic Analysis. This involves the determination of the thermal stress and comfort conditions using any of the thermal indices. The aim is to determine the nature of thermal stress and how to relieve it.

29. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  DESIGN OF SOLAR BUILDINGS Solar Geometry This involves knowledge of the sun’s position during periods of thermal stress and the design of sun-shading devices. It is often determined using graphic methods (sun- path diagrams), instrumental methods or computer programs.

30. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  DESIGN OF SOLAR BUILDINGS Thermal Analysis This is an analysis of the heat balance of the building. The traditional method uses the degree day and the total building heat loss per day. Other popular methods include, the Solar Load Ratio (SLR) method and computer programs.

31. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  DESIGN OF SOLAR BUILDINGS Choice of Appropriate Systems. Choosing a solar system of heating or cooling is based on factors such as client demand, availability, etc. After choosing, questions involving, type of device, air or water system, position and size of collector, etc., have to be answered.

32. ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria ARC 810: Building Climatology Department of Architecture, Federal University of Technology, Akure, Nigeria  DESIGN OF SOLAR BUILDINGS Integration. Integrating the chosen system into the building will cause a change in the existing thermal balance. Thus, requiring a review of the thermal analysis stage. This may necessitate an adjustment of the solar system parameters. It is repeated until an optimal solution is found.