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New slide Pack: Supplemental material on

New slide Pack: Supplemental material on. Cooling Towers Desiccant dehumidifiers Heat exchanger, hot water heat recovery Daylighting and complete replacement for slides 266-316 of the original package.

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New slide Pack: Supplemental material on

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  1. New slide Pack: Supplemental material on • Cooling Towers • Desiccant dehumidifiers • Heat exchanger, hot water heat recovery • Daylighting and complete replacement for slides 266-316 of the original package

  2. Figure 4.44a Cooling tower during normal operation. There is a cooling water loop between the cooling tower and the condenser of the chiller, and a chilled water loop from the evaporator through the building and back to the evaporator

  3. Figure 4.43: Schematic diagram of a cooling tower Source: ASHRAE (2001, 2001 ASHRAE Handbook, Fundamentals, SI Edition, American Society of Heating, Refrigeration and Air-Conditioning Engineers, Atlanta)

  4. Cooling Tower on Top of Medical Sciences BuildingWater is cooled through partial evaporation, to below the air temperature, then goes to the condenser of the “chiller” to remove heat, with the result that the chiller does not need to work as hard (and does not require as much energy) as it would if it had to make the condenser hot enough to dump heat directly to the hot outside air Source: Photo by Danny Harvey

  5. Fans on a Cooling TowerFans are used to force a greater flow of air next to the evaporating water, thereby forcing faster evaporation and greater cooling. Electricity energy for fans and pumps can be 15% or more of the electricity needed to operate the chiller itself. With absorption chillers, which can use waste heat for the cooling itself, even more electrical energy is needed to operate the cooling tower fans and pumps (and larger cooling towers are needed), thereby significantly reducing the overall benefit of using waste heat. As well, if the heat that drives an absorption chiller is taken from a steam turbine that generates electricity, there is a penalty in terms of reduced electricity production. Source: Photo by Danny Harvey

  6. Figure 4.44b Cooling tower as an evaporative cooler with direct connection of the cooling water loop and the chilled water loop

  7. Figure 4.41 Idealized solid-desiccant cooling system

  8. Desiccant wheel. Rotation rate: 2 rpm if passive (is dried only by the unheated outgoing air)60 rpm if active (outgoing air is heated before passing through) Source: Danny Harvey, photo taken at GreenBuild 2011 in Toronto

  9. Figure 4.45b Crossflow flat plate heat exchanger Source: Bower (1995, Understanding Ventilation: How to design, select, and install residential ventilation systems, Healthy House Institute, Bloomington, Indiana)

  10. Figure 4.46 Residential heat exchanger (as part of amechanical (fan-driven) ventilation system) Source: Danny Harvey, Construct Canada 2004 Conference exhibits

  11. Apartment heat exchanger (top)and heating or cooling coil (bottom) Damper Heat exchanger Fan Heating or cooling coil (depending on if hot or cold water is sent through it) Source: Danny Harvey, photo taken at GreenBuild 2011 in Toronto

  12. Figure 4.51 Heat exchanger for wastewater Source: Left: Vasile (1997, CADDET Energy Efficiency Newsletter December, 15–17) , Right: Danny Harvey, NSEA 2004 Conference exhibits

  13. Figure 4.57 Passive Light Pipe Source: Zhang and Muneer (2002, Lighting Research and Technology 34, 149–169)

  14. Active Light Tracking Skylight Source: Danny Harvey, photo taken at GreenBuild 2011 in Toronto

  15. Passive Daylighting (light louver) View from inside View from outside Source: Danny Harvey, photo taken at GreenBuild2011 in Toronto

  16. Source: Donald Yen, BCIT

  17. Daylighting effects Source: Donald Yen, BCIT

  18. Source: Donald Yen, BCIT

  19. The subsequent material replaces slides 266-316 of the originally-available file (many of the slides are the same, but many new ones – mostly photos – have been inserted to better illustrate the concepts)

  20. The latest (2012) foam insulation products available use (or could be using) a new generation of blowing agents (including some made in part from soy oil) that have substantially less GWP than those illustrated in the previous slides

  21. The latest (2012) foam insulation products available use (or could be using) a new generation of blowing agents (including some made in part from soy oil) that have substantially less GWP than those illustrated in the previous slides

  22. Applications of Foam Insulation • Structural Insulation Panels • External Framing and Insulation Systems (EIFSs) • Solid Insulation Forms • Spray-on Foam Insulation

  23. Various Insulation Levels with Structural Insulation Panels (SIPs), consisting of solid foam insulation, oriented strand board (OSB) for strength on one or both sides, or some other finish on one side Different facings on the insulation are illustrated here Different thicknesses (R-values) Illustrated here (divide by 5.678 to get RSI value) Source: Danny Harvey, Green Build 2011 exhibits, Toronto

  24. Example of EIFS (External Insulation Finishing System) Almost any finish is Available to go over the insulation, including those looking like bricks Expanded polystyrene foam insulation Behind the insulation is an undulating plate to permit drainage of any water that gets Into the system and behind the insulation. Thus, there is an air gap that is open at the bottom only. If there are any openings at the top, air will flow behind the insulation, short circuiting the insulation and rendering it next to useless. Other systems (which I prefer) have a gap between a separate rain barrier and the insulation on the outside of the insulation. Source: Danny Harvey, Green Build 2011 exhibits, Toronto

  25. Solid insulation forms – concrete is poured into the gap. The white is solid foam insulation that serves as the forms for the concrete, and remains after the concrete sets Source: Danny Harvey, 2004 Construct Canada exhibits, Toronto

  26. Use of spray-on foam in difficult-to-reach, irregular spaces during a renovation Before After (not quite finished, wraps around a chimney) Source: Danny Harvey, Toronto, 2010

  27. Before (left) and after (right). Note the hollow column (which formerly held acounter-weight)to the left of the triple-glazed window in the before photo – a horrendous thermal bridge! A gap (not visible) between the door joist and outside wall is also filled with foam insulation. Source: Danny Harvey, Toronto, 2010

  28. Before After Source: Danny Harvey, Toronto, 2010

  29. Solid-foam insulation example Source: Danny Harvey, Toronto, 2011

  30. Low-Embodied Energy Insulation • Cellulose (recycled newsprint, can be blown in) • Hemp • Wood-fibre products • Recycled blue jeans

  31. Hemp Insulation Source: Danny Harvey, 2009 Passive House Conference exhibits, Frankfurt

  32. Passive House Levels of insulation on display at the 2009 Passive House Conference in Frankfurt Full thickness of insulation under the entire roof area (including edges) Rain barrier with a gap behind it Wood fibre insulation Cellulose insulation Source: Danny Harvey, 2009 Passive House Conference exhibits, Frankfurt

  33. Insulation made from recycled blue jeans Source: Danny Harvey, Green Build 2011 exhibits, Toronto

  34. Demolition and replacement of existing buildings What matters from an energy point of view is how much energy would be required to make the materials that would go into the building that would replace the existing building, not how much energy was used in the past to make the materials in the existing building If the replacement building is designed to be highly energy efficient, the energy required to make a new building will usually be paid back through reduced annual operating energy use in only a few years Thus, from an energy point of view, demolishing old, energy-guzzling buildings and replacing them with new, efficient buildings is generally highly favourable

  35. Demolition (continued) However, the energy savings through renovation can often be almost as large as in replacing an energy-guzzling building with a new building For example, with regard to heating, we might go from 100 units to 20 units through renovation, and from 100 units to 10 units with replacement. The renovated building requires twice as much heating energy as the new building, but the savings is 80/90 = ~ 90% as large There are of course other considerations in the choice of renovation vs replacement, such as preserving the architectural heritage and reducing the generation of waste materials

  36. EXEMPLARY BUILDINGS FROM AROUND THE WORLD

  37. Residential Buildings

  38. The German Passive Standard: A heating load of no more than 15 kWh/m2/yr, irrespective of the climate, and A total on-site energy consumption of no more than 42 kWh/m2/yr For cooling-dominated climates, the standard is a cooling load of no more than 15 kWh/m2/yr

  39. Current average residential heating energy use: 60-100 kWh/m2/yr for new residential buildings in Switzerland and Germany 220 kWh/m2/yr average of existing buildings in Germany 250-750 kWh/m2/yr for existing buildings in central and eastern Europe 150 kWh/m2/yr average of all existing (single-family and multi-unit) residential buildings in Canada

  40. Comparison of PH standard with German standards for heating energy use in residential buildings Source: Figure by Danny Harvey, data compiled from various sources

  41. Saskatchewan House, 1977 – inspiration for the first Passive House in 1991 Source: The Encyclopedia of Saskatchewan, http://esask.uregina.ca/entry/energy-efficient_houses.html

  42. The first Passive House, Darmstadt, Germany, 1991 Source: Steinmüller (2008), Reducing Energy by a Factor of 10 – Promoting Energy Efficient Housing in the Western World, http://www.bsmc.de/BSMC-Factor10-WesternWorld.pdf

  43. The first Passive House community, Weisbaden Lummerlund, 1997 Source: Steinmüller (2008), Reducing Energy by a Factor of 10 – Promoting Energy Efficient Housing in the Western World, http://www.bsmc.de/BSMC-Factor10-WesternWorld.pdf

  44. Growth of Passive Houses in Germany, 1991-2003 Source: Steinmüller (2008, Fig. 3-7), Reducing Energy by a Factor of 10 – Promoting Energy Efficient Housing in the Western World, http://www.bsmc.de/BSMC-Factor10-WesternWorld.pdf

  45. Number of dwelling units meeting the Passive House standard in Austria

  46. Figure 4.78 Progressive decrease in cost with learning.Extra costs are about 5% of the construction cost in Europe, and about 10% of the construction cost in Canada. Source: Feist (2007, Conference Proceedings, 11th International Passive House Conference 2007, Bregenz, Passive House Institute, Darmstadt, Germany, 383-392)

  47. Occurrence of buildings meeting the Passive House Standard: Several thousand houses have now been built to and certified (based on measurements after construction) to have achieved the PH standard in Germany, Austria and many other countries in Europe The standard has also been successfully achieved in schools, daycare centres, nursing homes, gymnasia and a savings bank

  48. The PH standard is now the legally required building standard in many cities and towns in Germany and Austria City of Frankfurt: since 2007, all municipal buildings must meet the standard City of Wels, Austria: same thing since 2008 Vorarlberg, Austria: Passive Standard is mandatory for all new social housing Freiberg, Germany: all municipal buildings must meet close to the PH standard City of Hanover: since 2005, all new daycare centres to meet the Passive House standard (resolution only – legal status not clear)

  49. Modern Examples of Passive House Buildings

  50. The Biotop office building in Austria, with a combined heating+cooling energy demand of 19.4 kWh/m2/yr.

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