Review and Critical Analysis of International UHI Studies

are often difficult to measure but can often be indirectly measured. For example, the
elevated temperatures translate into costs incurred due to increased energy consumption;
� Costs incurred by implementing UHI mitigating technologies: these are the costs incurred
by implementing large scale UHI mitigation measures to combat temperature changes and
other undesirable UHI phenomena.
� Savings by implementing UHI mitigating technologies: the costs which are avoided by
implementing large scale UHI mitigation measures. This could be savings generated by
reducing the temperature and other undesirable UHI phenomena (naturally this is
dependent on the geographical location, season and time of day). For example, reductions
in temperatures in urban areas that experience predominantly cooling days often translates
into reductions in energy costs and thus economic savings ode to the UHI mitigation
technology implementation.
This section reports the findings from UHI studies that address the above issues. Costs associated
with the implementation of individual mitigation technologies at smaller scales have been
addressed in the technology section that follows. This section therefore, aims to report findings
which address either combined mitigation technologies at larger scales and examining the
implications of the UHI phenomena upon the economics at a state, national or global scale.
4.3.2 Economic Assessment Summary of Literature and Findings
All the studies that provided a broader economic assessment of the UHI countermeasures
emanated from the LBNL UHI Group and were US centric. The scales examined ranged from
city, state, national to Global. These studies used similar methodologies to infer the economic
savings by simulating the cooling/heating energy use using DOE building simulation models and
often used gas and electricity prices to provide an indication of the extent of the financial savings
‐ some studies looked at up scaling these results based on area specific data. The economic
assessments demonstrated significant financial savings (particularly for the warmer climates) but
indicated that the indirect savings potential was smaller than the total potential energy savings ‐
thus greatest economic benefits arise through mass implementation of UHI countermeasures that
achieve both direct and indirect savings over those that generate indirect only. Studies which
provided a global estimate for the potential economic benefits of reducing CO2 were also inferred
from the CO2 savings generated and the market trade price for CO2 – they demonstrated
significant financial benefits; however, require further investigation to improve reliability of
estimates.
4.3.3 Economic Assessment Literature Review
There are eight studies which provide an economic assessment at a broader level (as described
above) [025, 027, 028, 033, 035, 112, 142, 176]; whereas all of the mitigation technologies to varying
levels of rigor have had economic assessments conducted. All the studies that provide this
broader economic assessment emanate from the Lawrence Berkley National Laboratory ‐ Urban
Heat Island Group. Of these papers the economic assessments are made at the following scales:
City [033]; State [025, 176]; National [027, 028, 112, 176]; and Global [035, 142].
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