Heat Island Effects

Oct
24

Heat Island Effects

Simply put – Cities are

Islands of Heat.

Cities of a million people or more raise temperatures by 3⁰C in the day and a whopping 12⁰C at night. This does have a dramatic effect on energy requirements, air pollution and greenhouse gas emissions, heat related illnesses and water quality. Worldwide, communities are coming to understand more of the demands faced living in city confines and strategies are being developed to overcome them.

Consider the heat generated by the shopping mall car park on a sunny day, or that contained in your roof, all this goes to heating the planet, and of course in a very direct way touches us and our environment.

Increased demand for Energy: Ten years ago it was only the bank manager who had an air conditioner. Today our bedrooms have got them in. One study has indicated that the heat island effect is responsible at peak for 5 – 10⁰C of the city energy requirements just to cool it down.
Elevated energy requirements cause increased pollution emissions. Obviously, if more air conditioners are running, more by products are dumped into the atmosphere.
Higher temperatures cause greater discomfort and lead to physical breakdown. Further, when we operate at higher temperatures we to need cooling and as such our demand for water, or other cool drinks.
Raising water temperatures encourages the multiplication of water borne bacteria, mould and other challenges to our livelihood.

Homeowners can improve the situation by:

Painting of their roofs with a reflective shield. The pure acrylic version, with mica sediment, distributed by Mica stores has fantastic cooling properties. The colours available are aesthetically good and the expense worthwhile.
Planting shade producing trees. Scientists have estimated that the present value of savings to the American homeowner who planted three trees would be $210 per tree – $600+
Installing shade cloth covered car ports. These not only protect the environment but go a long way to protecting our second most expensive asset, our motor vehicles.
Instead of using tar on the driveway use a higher reflecting product like cement, or lightly coloured pavers.

Other Benefits of Trees:

Improve quality of life
Increased value of property
Decreased rain run-off water
Increased production of Oxygen

Conclusions:

Cool surfaces (cool roofs and cool driveways) and urban trees can have a substantial effect on urban air temperature and hence can reduce cooling-energy use and smog.

“It has been estimated that about 20% of the national cooling demand in America can be avoided through a large-scale implementation of heat-island mitigation measures. This would amount to savings worth over $4 Billion per year by 2015 in cooling electricity savings alone – total savings could be as high as $10 Billion per year”.