The world is getting hotter, West Africa in particular Ghana is becoming very hot. Some days the capital city of Accra can be unbearably hot and humid, due to global warming the average daily temperature is now around 30 degrees, this average daily temperature is due to rise by 5.4 degrees by 2080.
Due to the rising temperatures this will also result in the rise of energy bills for most of us. Higher temperature means more use of electronic cooling systems in our homes.
Although these cooling methods can give us a temporary fix, some can do more damage than good.
Cons of using Fans
Fans are low in energy consumption and are great for circulating air, but it can attract a lot of dust, especially in the dry season where dust is at an all time high, which can trigger sinus allergies.
Cons of using Air conditioners
Air conditioners are a great way to get instant cooling relief but they are not always great for our health and also contribute to global warming therefore creating a vicious cycle.
The more we turn on our A/C units the more hot air is being extracted from the internal room and being put back out to the external environment. This in turn is contributing to heating up the outside temperature, can you image in a hot city like Accra where the daily average is in the 30’s and thousands of AC’s working at the same time, all that hot air blasting from every AC extractor making our city feeling even hotter.
AC units also use hydro fluorocarbons (HFCs) and chlorofluorocarbons (CFCs) that emit pollutants that put holes in the ozone.
They also need a lot of energy to power, the more we use them the more fossil fuels being burned to create energy to power.
If AC units are not regularly cleaned they can be a source of health issues. Air contamination can become a severe problem that contributes to respiratory illnesses in people. Additionally, air conditioning can lead to problems, such as colds, fevers, headaches and fatigue.
"The warmer it gets, the more we use air conditioning. The more we use air conditioning, the warmer it gets. Is there any way out of this trap?" – Stephen Buranyi for the Guardian
Homes in 50's & 60's Ghana
Our company really believes in learning from the past and what the previous generations did with architecture and materials to cope with the tropical climate. In a country like Ghana for example, when you look back at older buildings, they were really built to deal with the tropical climate.
Homes built in the 50,s and 60,s tends to be well ventilated, positioning is favorable to allow maximum ventilation and cooling, windows that are used are normally louvered to help further with cross ventilation in the home. In some homes you will get fan light windows to help rising hot air escape, trees shade the homes and even flooring is traditional terrazzo which keeps the home extra cool because of the natural river stone materials that is used, terrazzo flooring is also long lasting, highly durable and non toxic.
Even if you go as far back as the traditional mud home, earth is the perfect material to build with as it’s proven to keep the interior temperature cool.
Today in Ghana, homes look a lot different and have a lot of western influence without taking into consideration how it will adapt to the hot tropical climate.
When constructing your new home there are plenty of natural cooling strategies and practices that you can incorporate to create passive or low cost cooling.
4 ways to naturally cool your home
1. Geo thermal cooling (underground cooling system)
Geothermal cooling is a renewable energy system that moves heat from your home underground, thus using below the earth’ s surface under your home like a heat sink.
Geothermal energy cools air by moving hot air through a geothermal heat pump, therefore moving heat from inside your home to the cooler environment 20 feet under the earth's surface. Thermal heat pumps are low in energy when connected to the grid or can be solar if you want to go completely off grid with your cooling.
Due to the mass of the earth below, geothermal systems can cool even extreme heat, great for cities like Accra. Another environmentally friendly element of geothermal cooling systems is the hardware: The below ground loop can last for generations, and the above ground equipment for decades.
2. Louver windows
Near the equator, windows facing north or south will absorb the least heat. In warm tropical climates like Ghana, a louvered window is one of the best types of windows for natural ventilation. However, as air-conditioning & sliding windows became more popular louvered windows became uncool.
Today when building a home in Ghana, the thought of installing louvered windows isn’t always the first choice or doesn’t even cross the minds of the client. This is unfortunate as this is the best type of window and can outperform any new modern window type.
Louvred windows have many advantages in tropical regions. They offer energy-efficient ways to light and cool a home in warm climates naturally.
When fully open they allow for almost up to 100% ventilation.
Today louver windows have come a long way from how they were 50 years ago, modern louvered windows offer a more sophisticated locking mechanism also some have solar on the blades to help capture energy for your home.
3. Clay roof
Roofing is one of the most important components when it comes to building your home that is often overlooked. Its important that you choose the right material for your roof as this can be the difference from living in a hot box or having a roof that can absorb the heat coming into your home.
In hot climates, clay roof tiles are one of your best options. With this kind of roof it can maintain a cool temperature in your home. It does this by preventing the sun rays from heating your building and also helps in maintaining optimum temperature.
Many people like this material because it is environmentally friendly, you can easily recycle it, also they are fire and weather resistant too. In harsh weather conditions, they are less likely to deteriorate. Compared to other roof materials such as asphalt, it lasts longer and it does not require a lot of maintenance, it is less likely to develop mildew or moss, and when these develop, they can be easily washed away.
4. Rammed Earth Walls
Rammed earth walls have great thermal mass because they are dense and heavy, so it can absorb and store significant amounts of heat.
Walls constructed using rammed earth contain less than one twentieth of the embodied energy of traditional brick and mortar walls.
Rammed Earth walls have a high thermal mass absorbing heat energy through the day and releasing it into the building as temperatures fall at night. Experiments have shown that rammed earth walls can actually reduce daytime temperatures by 4 or 5 degrees.
Would you consider any of these options when building your home? Its definitely worth incorporating some of these elements into your build for a comfortable living environment. A lot of components that are used for building in Africa, particularly Ghana are being imported and does not necessary perform the best for our climate.
Using what is available around us to naturally cool our buildings will result in positively impacting global warming and having a healthier home free of toxins.