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MT 1 will be on Wednesday Oct. 31st, 2012 at 1830.

MT 1 will be on Wednesday Oct. 31st, 2012 at 1830. MT 1 will include: Introduction (Chapters 1-2) Cars, planes, freight (Chapter 3,5,A, some of 15 on freight) Wind (Chapters 4, B) Heating and Cooling (Chapters 7, E). Heating and Cooling. Domestic Water Heating.

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MT 1 will be on Wednesday Oct. 31st, 2012 at 1830.

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  1. MT 1 will be on Wednesday Oct. 31st, 2012 at 1830. MT 1 will include: Introduction (Chapters 1-2) Cars, planes, freight (Chapter 3,5,A, some of 15 on freight) Wind (Chapters 4, B) Heating and Cooling (Chapters 7, E)

  2. Heating and Cooling

  3. Domestic Water Heating Heat Capacity: (CV) Amount of heat necessary to change the temperature by 1 ºC per unit volume For water CV=4100 J / liter / ºC Energy required to heat water in a bath from 10ºC to 10ºC ?

  4. Domestic Water Heating

  5. The two dominant reasons why buildingslose heat are:

  6. The two dominant reasons why buildingslose heat are: 1. Conduction – heat flowing directly through walls, windows and doors; 2. Ventilation – hot air trickling out through cracks, gaps, or deliberate ventilation ducts.

  7. Conduction Loss: Related to the conduction of the wall

  8. Ventilation Loss: The number of changesN of the air per hour, The volume V of the space in cubic meters, The heatcapacity C, The temperature difference DT between the inside and outside of the building

  9. 78 % 22 %

  10. Total leakiness of the house: 322 W/ºC = 7.7 kWh/d/ºC The heat-loss parameter of this house (total floor area88m2) is: 3.7 W/ºC/m2 Let’s use these figures to estimate the house’s daily energyconsumptionon a cold winter’s day, and year-round.

  11. The heat-loss parameter of this house is reduced by about 25%, from 3.7 to 2.7W/ºC/m2. • Further reduced the consumption by reducing the thermostat setting from 20 to 17ºC. 1.1W/ºC/m2required of a “sustainable” house in the new building codes

  12. Air-exchange Once a building is really well insulated, the principal loss of heat will bethrough ventilation (air changes) rather than through conduction. Hot Air Cold Air

  13. Air-exchange Once a building is really well insulated, the principal loss of heat will bethrough ventilation (air changes) rather than through conduction. Hot Air Cold Air Can we cool down the hot air before it leaves the house?

  14. Nose

  15. Exercise: Consider a 100 m2 sustainable house in İstanbul with 1.1W/ºC/m2energy consumption. Let’s use these figures to estimate the house’s daily energyconsumptionon a cold winter’s day, and year-round.

  16. For a cold Day: DT=20ºC 1.1x20x100 = 2200 W 2200 W consumed during one day : 2.2 kWx24 h=52.8 kWh/day

  17. For an average day: DT= ? http://weather.sg.msn.com/monthly_averages.aspx?wealocations=wc:TUXX0014&q=%C4%B0stanbul%2C+TUR+forecast:averagesm

  18. For an average day: DT= 20-14 ºC 1.1x6x100 = 660 W 660 W consumed during one day : 0.66 kWx24 h=15.8 kWh/day

  19. Exercise: What are the main mechanisms that lead to heat losses in a building?

  20. Exercise: What are the main mechanisms that lead to heat losses in a building? Conduction Ventilation

  21. Exercise: Looking at the plot below estimate the energy consumption of a modern 50m2 apartment in Istanbul in February and in November. Assume energy consumption to be 1.1W/ºC/m2 for the modern apartment.

  22. Exercise: Rate at which energy is produced by a wind mill is given by the equation below. Interprete this equation and describe the factors effecting the generated power.

  23. Exercise: Heat loss due to conduction is quantified by the equation below. Interprete this equation and describe the factors effecting the generated power.

  24. Exercise: Heat loss due to ventilation is quantified by the equation below. Interprete this equation and describe the factors effecting the generated power. N number of changes of the air per hour

  25. Exercise: Describe the main principle of energy generation with a windmill. What is the nature of energy in the wind and how is it converted to electricity?

  26. Exercise: What can be done to reduce the heat losses due to conduction and ventilation in a building?

  27. Exercise: What are some exemplary geographic locations where wind speed is highest in Turkey? What are the average wind speed values n those regions? How does wind speed change with altitude?

  28. Exercise: What are the main parts of an AC power generator. Describe its principle of operation.

  29. Exercise: What is heat capacity? Can you estimate the energy required to boil water in a kettle that is totally filled? For water CV=4100 J / liter / ºC

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