Beating the heat – innovative ways to cool buildings and people
Hot weather is great for a beach holiday or a picnic in a shady park, but many people find the heat distracting when it comes to goal-oriented pursuits. High temperatures can make many activities more difficult, such as working, sleeping, or even thinking.
Luckily, many people are blessed with the gift of air conditioning – but it’s a mixed blessing. Electrical heating and air conditioning systems (HVAC) now account for 40% of global energy consumption in buildings, according to the International Energy Agency. That translates into high costs as well as unsustainable demands on both infrastructure and resources. So it is not surprising that the search is on for new and better ways to stay cool in hot places.
The birth of the cool
Modern coolant-powered air conditioning was invented on 17 July 1902 by Willis Carrier as a way to help a printing company combat problems of variable humidity. Back then, people did not think much about natural resources or environmental pollution, and that way of thinking continued over much of the 20th century. As the modern electrical power grid developed, power-intensive HVAC systems became a staple of modern buildings.
Indoor climate control made urban summers much more bearable. It also enabled the expansion of the modern urban model – pioneered by northern cities in Europe and North America – to southern cities previously deemed too hot. Atlanta and Dubai, for example, never would have developed into economic centers without air conditioning.
Air conditioning will not disappear any time soon, but it can be supplemented by traditional means that help reduce the amount of energy needed to cool.
Traditional ways to beat the heat
People living in hot places have always found ways to make do. Many of these tried-and-tested solutions are still used today: high ceilings, latticed windows, dark shades, rammed-earth walls, ice blocks, public fountains, and midday siestas. But for all the simplicity and sustainability of traditional methods, they began to disappear in the face of widespread air conditioning.
Simple solutions still work, though. Here’s our list of ten low-impact ways to beat the heat.
The Urban Hub Top 10 – Simple solutions for keeping cool
- Take a nap in the heat of the day.
- Get wet with a moist towel, or soak your feet.
- Drink non-alcoholic fluids – especially chilled beverages.
- Eat spicy food to raise your internal temperature.
- Wear loose, light-colored clothing.
- At home, block the sun’s rays with curtains or shades.
- Don’t use the stove or oven.
- Change your bed sheets more often.
- Sleep on the floor – hot air rises!
- Let cool evening air in; keep hot daytime air out.
Bringing back tradition with technology
To reach the next level in climate control, we have to first look back before moving ahead. All around the globe, architects and other visionaries are looking into traditional, low-impact, highly sustainable solutions for keeping cool and are using modern technology to deploy them in new ways. For instance, modern passive cooling techniques are built on age-old methods of using differences in air pressure, thermal mass, and evaporative cooling, as well as green walls and roofs.
Bioclimatic design and biomimicry principles
Bioclimatic design goes a step further, making the specific local climate a primary consideration when creating a cooling strategy. Biomimicry is one aspect of this, which looks directly at how the local environment has adapted to the climate. For example, Harare’s Eastgate Centre – Zimbabwe’s largest office and shopping complex – cuts the energy required for cooling with a design that mimics the self-cooling mounds of indigenous termites. And in Algiers, a PTT (post office) building uses a sand-dune design to scoop up cool mountain winds.
It’s always possible to benefit from local conditions. Something as simple as natural ventilation or shading, for instance, can be used to moderate the indoor climate and minimize energy consumption. Smart building control systems can automatically adjust windows and shades based on preprogrammed weather parameters and sensors. The new U.S. Embassy in Monrovia, Liberia, is a good example of local adaptation. Certified LEED Gold, it was specifically designed to adjust to its hot, humid, high-rainfall location. It utilizes waste heat for cooling, rainwater for drinking, and solar energy for power.
African termites inspire clever cooling solutions in Harare:
Kinetic architecture and “moving skyscrapers”
Kinetic architecture refers to structural elements that can move without compromising overall building integrity or stability, such as a drawbridge or the retractable roof of a sports arena. These are normally not considered smart solutions, but when moving components are utilized for regulating temperatures in buildings, they become smart.
Instead of shades, for example, some architects are integrating kinetic façades into their designs. The “One Ocean, Thematic Pavilion EXPO 2012” in Yeosu, South Korea, uses a moving, gill-like façade to provide shade or let light in. The Al Bahr Towers in Abu Dhabi use a similar method of automatic external shading, with a look inspired by the Islamic latticework shading technique called “mashrabiya.”
The award-winning Al Bahr Towers in Abu Dhabi combines traditional mashrabiya sun diffusion techniques with origami-inspired design and modern automation to reduce the air conditioning load of the building by 50-60%.
Making tomorrow’s cities sustainably cool
New approaches to ventilation and air conditioning offer greater sustainability and energy efficiency. By combining traditional tactics for “beating the heat” with modern technology, they also open up new vistas for architectural planning and design. In future Urban Hub articles, we will also look at how these innovations can assist in addressing the dangers to personal health in “sick buildings,” as well as in reducing heat-island effects in urban areas.
By combining the wisdom of the past with the tools of the future, tomorrow’s cities will be better positioned to take the heat off residents sustainably and without breaking a sweat.
How do you keep cool in hot weather – any good tips?