Sustainability and Design | Energy Efficient design techniques
In one of our earlier articles, we made a questionnaire on “Energy efficient Techniques”. In this article, we will discuss the answers to each of those questions.
Energy Efficiency Questionnaire
Achieving Energy Efficiency through Urban Planning
What is Energy Efficiency? Define Energy Efficient Architecture.
Energy Efficiency implies on using less energy to required for various products and services without compromising on the need of the usage.
“Energy efficiency” and “energy conservation” are not similar.
Let us study with the help of examples:
Examples of Energy Efficiency
When the walls and roofs are insulated, the use of air conditioners and heating systems is reduced while still keeping the indoor environment comfortable.
When a refrigerator or washing machine is replaced by the same appliance that require lesser amount of energy to carry out the same function is called “energy efficiency”.
Examples of Energy Conservation
When a tube light is switched off during day time, it can be termed as energy conservation.
For what purpose is the significant amount of energy used in homes?
Energy is mainly used for cooling and heating purposes. Air conditioners and heating systems require extensive amount of energy for its functioning.
Hence, designers must design the house in such a way that the use of air conditioners and heating systems can be minimized without compromising on the comfort.
What is to be done in order to avoid the extensive use of air conditioners for cooling?
The orientation of the house/any building should be taken into consideration. Climatological aspects of the place have to be studied before designing the structure.
How important is it for the designers to consider orienting the structure? And why?
Proper orientation will help in regulating the air flow through the structure. It will also help in decreasing the amount of sunlight incident on the house. It depends on the climate of the place.
What can be done in case of countries with extreme cold climate?
In cold countries, it is essential to orient the structure in such a way that the sunlight falls into the space and helps keep the house warm whereas in countries with hot and humid or warm climate, orientation of the building should be done in a way to avoid the sunlight entering the living areas.
Also, use of trombe walls are to be adopted. Trombe walls act as thermal mass. They absorb the heat during the day time and release it at night. This will help in keeping the interior of the homes warm. This could be termed as Passive Heating.
What is Passive Solar Cooling Concept? How can be be incorporated?
Passive Solar Cooling concept in itself is a vast topic.
- By Use of chimneys,
- Wind towers
- Courtyard cooling effect
- Earth air tunnels etc.
What can be done in order to improve the degraded environment?
Environmental quality is of great concern here. Degraded environmental quality degrades the life of living beings on earth. Proper landscaping and horticulture is the key here.
So this was about the environment and the way in which we could reduce the consumption of energy with the use of Passive Techniques.
Now let’s move on with the discussion of Shading devices.
How are shading devices useful to achieve energy efficiency?
Use of shading devices is very important and can be used in a very effective way.
Day lighting employed to lighten the house mainly depends on the design and efficient use of shading devices.
It reduces heat gained by the building which in turn helps to reduce the cooling requirements.
It also enhances the natural lighting in the interior space.
How far can the reduction in consumption of energy be achieved?
In the range of 5% to 15%.
Improvisation in the user visual comfort. It helps in reducing glare and contrast ratios which cause discomfort.
It can also be achieved with the use of materials in building Construction
Which building materials account for high usage of energy?
According to an expert witness testimony from an asphalt contractor in NSW, extensive amount of energy is used in the production of steel, aluminium, cement, clay bricks, tiles, glass etc.
What can be done to prevent the use of extensive amount of energy for production of these materials?
The production processes and procedures have to be carefully scrutinized. The manufacturers have to make an effort to conserve energy.
This can be done by searching for alternatives of production processes.
Use of cheaper and non-premium fuels can also be undertaken.
What has to be done in order to contribute to Energy Efficiency with respect to use of building materials?
Use of less materials
Use of local materials
How will use of local materials help in achieving energy efficiency?
If we use local materials on site, it will be beneficial in two ways:
First, it will save extensive amount of cost (cost effective)
Secondly, it will save transportation costs since it will be available locally. This will help save the precious fuel.
Lesser use of high energy materials
Reduction in the thickness of walls (This will help in reducing the building materials required for construction.)
Lessening the finishes used for the interiors as well as the exteriors. This involves a lot of wastage of materials.
Selection of lower energy structural systems
(Some people may recommend using load bearing walls instead of reinforced concrete or steel frames. But that is not very practical. So, we can ignore this aspect because replacing reinforced concrete walls with load bearing walls is not easy. Load bearing walls occupy lot of space.
Today, buying land has become an expensive business. So, utilizing every inch of land becomes very important in order to minimize losses.
And if we are to go for load bearing walls instead of reinforced concrete walls, then the thickness of the walls used for construction will be double of the thickness of RCC walls.
Construction of low rise buildings in place of High rise wherever possible.
Well, how far could this be achieved…??
Let’s discuss this with the help of an example.
Say for a city – Hyderabad/Mumbai
This could be possible if we were to concentrate the core of the city with low rise buildings. The outer ring road of the road could be developed with high rise residential and commercial buildings.
This will help keep the balance of the city. This will help in reduction of pollution, decrease in traffic and also keep the buildings to the human scale.
How will the Thermal Insulation of walls and roofs help in saving energy?
Previously, we talked about how we could reduce the use of air conditioning devices for heating or cooling purposes by following Passive cooling or heating techniques.
But if we are to consider extreme climates (cold/hot), then inspite of following the passive techniques, the need for air conditioning devices still persist.
What can we do to after installing air conditioning devices after installing them? How do we use them in order to save energy?
While installing air conditioning or heating system in a building, heat gain is the factor which is very important to be considered.
Heat gain through walls and roof becomes very important.
Use of proper design techniques
Appropriate choice of materials
Designing roofs with thermal insulation with under deck or with over deck insulation. This will help in reducing the heat gain from roof.
For making walls, cavity walls, hollow bricks or aerated concrete blocks could be used for providing thermal insulation.