Review and Critical Analysis of International UHI Studies

Recommendations

Info

� residential sector – not yet cost effective except for premium roofs (metal, tile), could be very cost effective especially when ducts are in attic In other words cool roofs become a cost effective option in many cases where other aspects of the building and HVAC design are inefficient. 5.4.2 Cool Pavements (Roadways) The existing economic calculations regarding cool pavements suggest they struggle to break even if just the life cycle value of energy and local pollution abatement are considered. If the value of the negative radiative forcing abatement impact is monetized they become far more cost effective. Reflectivity of pavements is also a safety factor in visibility at night and in wet weather, affecting the demand for electric street lighting. Street lighting is more effective if pavements are more reflective, which can lead to greater safety; or, alternatively, less lighting could be used to obtain the same visibility. These benefits have not yet been monetized. 5.4.3 Economics of Shade Trees UHI reduction from tree planting has been found to lower peak urban diurnal temperatures by 0.3 to up to 3K and to give air conditioning savings of $5‐$10 per 100m 2 of roof area for residential and commercial buildings. For example a study of the impact of planting 100m trees in the Los Angeles basin estimated $270 million from direct and indirect energy savings and smog reduction benefit of which the value of smog reduction accounted for about 2/3 rds of the total. The present value of planting trees was found to be $68 per tree for the direct energy savings and $24 per tree for indirect energy savings. The present value of smog savings was about $120/tree. Estimates of the cost of planting, pruning and tree removal vary and have been found to vary from $45 to $500 per tree. On this basis tree planting is often not cost‐effective in pure energy savings terms and even if the value of local air quality improvement is incorporated the cost‐ benefit calculations do not always favor tree planting, however, the aesthetic and quality of life benefits of greener spaces are not included in this assessment and they may well tip the balance firmly in favor of greater urban greenery. 5.4.4 The Value of Mitigation Benefits from the Negative Radiative Forcing Effect The value of the negative radiative forcing effect is purely in terms of the public good value of reduced global warming. According to the only global estimate so far conducted this would be worth a massive US$1,100 in carbon offsets were CO2 valued at �$25/tonne of CO2 and were all viable urban roofs and pavements to have their albedo increased by 0.1. This is equated to a 44 Gt CO2 emission offset. Review and Critical Analysis of International UHI Studies Page 97
5.5 Opportunities for Scale Up (Barrier and Rate Analysis) 5.5.1 Introduction In order to understand the actions that can either catalyze or hinder the mass adoption of UHI strategies and technologies we attempt to identify the typical barriers/catalysts that can affect the deployment rate and large scale urban city adoption across the world. Some of the reported barriers have been identified through the literature reviewed and others are based upon experience from other sectors. Naturally, the type and extent of the barriers faced across different regions will depend upon numerous parameters and thus this process seeks to provide a high level identification of the broad issues in some cases elaborated through UHI specific examples. 5.5.2 High‐level Barrier Diagram The diagram illustrated below provides a high‐level interpretation of the key barriers and/or catalysts for the Urban Heat Island implementation and scale‐up with some key examples listed under each category. The section to follow provides: a definition of each of the categories, an analysis founded on the 5A’s analysis conducted on each category, factors which can affect the rate of scale‐up and thus some recommendations to overcome barriers and enhance the catalysts. Culture / Tradition / Languages •Transferability of technology between different cultures •Transferability of information between different cultures •Spatial and infrastructure constraints of mass implementation of UHI measures •Public opinion of mitigation measure impact on residential dwellings •Legislative constraints e.g. conservation/protection orders Urban Design/Planning Technological •Degree of technology development and maturity •Suitability of existing technology •Existence of collaborative R&D efforts to develop UHI technology •Existence of associations to advocate technology •Material availability, costing and benefits/drawback •Existence of practical infrastructure constraints •Cost of technologies dependent upon geographies •Technology performance variation due to climate/geography •Ability to source technology materials locally •Technology applicability to different climate types Climate / Geography Information •Existence of practical and technical knowledge base •Accessibility of key studies and their benefits •Affordability of information to key stakeholders •Costs associated with generation, collation and presentation of information •Level of government funding available for UHI and related incentive programs •Costing of ancillary benefits/drawbacks of technology •Initial cost of technology •Life‐cycle cost of technology Economic Institutional •Coordination and buy‐in of authorities •Institution tools and knowledge for decision making •Size of authority budget •Overlap of responsibilities between authorities •Understanding and transferability of other institutional models •Attractiveness of non‐ mandatory programs •Capacity and will of institutions to develop and implement policy •Level of technical standard harmonization •Level of policy coordination on technology transfer and promotion •Policy and building code timescales •Level of information to support policy development Policy / Legal Review and Critical Analysis of International UHI Studies Page 98 UHI Strategy and Technology Barrier/Catalyst Identification
Page 1 and 2:
Assessment of International Urban H
Page 3 and 4:
Comments iii Bibliographic Report a
Page 5 and 6:
List of Acronyms and Abbreviations
Page 7 and 8:
TABLE OF CONTENTS vii Bibliographic
Page 9 and 10:
ix Bibliographic Report and Study o
Page 11 and 12:
xi Bibliographic Report and Study o
Page 13 and 14:
The mitigation technologies were fo
Page 15 and 16:
a forward path; provides an economi
Page 17 and 18:
2.1.1 Population Size/Density Popul
Page 19 and 20:
workday effect and weekends. Studie
Page 21 and 22:
Some UHI impacts are positive such
Page 23 and 24:
correlation with vehicles and traff
Page 25 and 26:
2.2.4 Peak Power Peak power describ
Page 27 and 28:
temperature and climate, thus chang
Page 29 and 30:
3 QUANTITATIVE MODELING & SIMULATIO
Page 31 and 32:
The following papers use a number o
Page 33 and 34:
Another study in Japan simulated ai
Page 35 and 36:
This paper applied a model to calcu
Page 37 and 38:
3.2 Simulations of UHI 3.2.1 Introd
Page 39 and 40:
A study in France sought to find ou
Page 41 and 42:
Traffic flow was calculated using c
Page 43 and 44:
Implementation Issues 4 North & Asi
Page 45 and 46:
These studies were founded primaril
Page 47 and 48:
(humidification and heat sink insta
Page 49 and 50:
emissions and the tree topology rel
Page 51 and 52:
At a City scale one study focuses o
Page 53 and 54:
This section reports the findings f
Page 55 and 56:
Recent steps taken in cities in the
Page 57 and 58: � Most US States encourage tree p
Page 59 and 60: o 29 German cities offer subsidies
Page 61 and 62: 4.5.1 Review for Cool Roofs: 4.5.1.
Page 63 and 64: the global emitted CO2 offset poten
Page 65 and 66: standards to promote the cool roofs
Page 67 and 68: The expected savings generated in c
Page 69 and 70: � The degree to which the change
Page 71 and 72: enefits are complex to measure dire
Page 73 and 74: controls of the active cooling/heat
Page 75 and 76: temperature increases due to paveme
Page 77 and 78: curb‐side planting. Data gatherin
Page 79 and 80: location, orientation, growth/morta
Page 81 and 82: seasons, climate types, etc. Furthe
Page 83 and 84: the summer than the winter, thus ra
Page 85 and 86: A study in Japan tested the effect
Page 87 and 88: One US study written in 1998 seeks
Page 89 and 90: This section reports the findings f
Page 91 and 92: planning approach. Medium resolutio
Page 93 and 94: Urban design and planning is a comp
Page 95 and 96: 5 CRITICAL REVIEW OF UHI COUNTERMEA
Page 97 and 98: � Implementation Issues: The esti
Page 99 and 100: savings are used over solutions tha
Page 101 and 102: � 10.5 MtCO2 emissions per year f
Page 103 and 104: � Preparation: Substantial prepar
Page 105 and 106: 5.3.3 Green Roofs and Urban Green A
Page 107: 5.4 Economic Review The magnitude o
Page 111 and 112: technology, it evaluates the availa
Page 113 and 114: Availability: the level and type of
Page 115 and 116: integration would make them accepta
Page 117 and 118: Awareness: Planners and designers w
Page 119 and 120: would seek to incentivize UHI count
Page 121 and 122: homeowner for example to choose whe
Page 123 and 124: Planning issues for new builds, the
Page 125 and 126: 5.6.4 Energy Efficiency Measures Pl
Page 127 and 128: � Political will - The government
Page 129 and 130: not to create dedicated policy vehi
Page 131 and 132: � When developing costing analyse
Page 133 and 134: 7 GLOBAL SCIENTIFIC PANEL 7.1 Intro
Page 135 and 136: an understanding of planning policy
Page 137 and 138: Role Name Institution Country of Or
Page 139 and 140: Role Name Institution Country of Or
Page 141 and 142: sustainable architecture. He is an
Page 143 and 144: energy buildings, natural and mixed
Page 145 and 146: Name: Hashem Akbari Current Positio
Page 147 and 148: momentum in cities are measured and
Page 149 and 150: Ms MacDonald was formerly Director
Page 151 and 152: Name: Dr Dale Quattrochi Current Po
Page 153 and 154: Name: Joe Huang Current Position: L
Page 155 and 156: State University. He is former Pres
Page 157 and 158: Bank for Reconstruction and Develop
Page 159 and 160:
planners/designers are equipped wit
Page 161 and 162:
Paper Ref Title of Paper Author Ins
Page 163 and 164:
Page 165 and 166:
Page 167 and 168:
Page 169 and 170:
Page 171 and 172:
Page 173 and 174:
Page 175 and 176:
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Page 183 and 184:
Page 185 and 186:
Page 187 and 188:
show all

Review and Critical Analysis of International UHI Studies

Create successful ePaper yourself

Delete template?

Save as template?