Green buildings, the way to go

It is estimated that buildings worldwide account for about one third of the total energy consumption and therefore can be considered as one of the single largest consumers of energy in the world. 

Although buildings themselves don’t consume energy, the various systems such as cooling, heating, lighting, ventilation and vertical transportation systems which are required to provide a comfortable and safe environment for the occupants account for most of the energy consumed in buildings.

In addition to the energy consumed to operate buildings, they also account for significant “embedded” energy use which is the energy consumed in manufacturing of the raw materials and finished products such as cement, steel and glass used in the construction of buildings.

The increased concern over climate change and the role of carbon emissions has led to growing awareness on the importance of the environmental impact of buildings. Since buildings account for significant energy use during their entire life-cycle from construction to operation and because most of this energy used in buildings is generated using fossil fuels which account for a significant percentage of carbon emissions worldwide, the global effort to minimise the environmental impact of buildings has been gathering momentum in the last few years.

Since organisations around the world are also constantly under pressure to reduce operating cost to improve their financial performance, there is also a strong economic case to reduce the energy consumption in buildings which is one of the major operating costs of a building. 

These two strong drivers which are influenced by environmental and economic concerns have led to the concept of “green buildings” (also called sustainable buildings) which are buildings designed and operated to minimise the impact on the environment. 

Green rating systems

In developed and developing countries, the concept of green buildings has been gathering pace and has led to the increase in number of new buildings designed to be green and also the “greening” of existing buildings.

This movement to make buildings green has led to various rating schemes designed to benchmark buildings based on individual systems and overall performance. Some of the widely accepted international rating schemes include LEED (leadership in energy and environmental design), BREEAM (building research establishment environmental assessment method), BEAM (building environmental assessment method), CASBEE (comprehensive assessment system for building environmental efficiency), Green Mark, Green Star and GBI (green building index).

All these rating schemes are designed to assess the environmental performance of buildings with respect to a combination of criteria such as energy efficiency, water efficiency, environmental protection, quality of indoor environment and innovative features.

Cost and benefits

A frequently asked question about green buildings is how much additional cost would need to be incurred to make a new or existing building green. Although in many cases, it may not be necessary to pay a premium for green features because if they are incorporated during the design process of a new building, the cost avoidance from the conventional design feature which it replaces can offset the cost of the green feature, in general, the “green premium” is considered to be about 2% to 3%.

This premium has been the single biggest obstacle to green buildings because it is commonly perceived to be much higher. The green premium is expected to drop further with the increase in the number of green buildings due to the reduction in cost associated with construction and design of green features making green buildings even more acceptable.

Even at the current level of premium that may be required, the economic and environmental benefits of green buildings far outweigh this extra cost. Economic benefits mainly result from reduced energy and water cost and are typically about 30% and 50%, respectively. Other economic benefits that are less tangible include improvement in productivity of the building occupants due to improved indoor conditions like space temperature, air quality and lighting levels.

Although the economic benefits that result from reducing the environmental impact of green buildings like the reduction of carbon emissions, pollution and waste cannot be easily quantified at a building level, at a global level, the positive contributions are immense and essential to mitigate climate change and ensure environmental sustainability.

Green buildings in Sri Lanka

Although a number of buildings have been Green Certified in Sri Lanka, the adoption of this concept has been generally slow compared to many other countries. Other than the LEED rating tool, the two other commonly used green rating tools in Sri Lanka are GreenSL and CIOB Green Mark. 

The main barriers to the adoption of the concept of green buildings in Sri Lanka can be considered to be the lack of understanding of its benefits and the extra investment usually required to green a building.

Therefore, creation of better awareness of the potential benefits such as the reduction in energy and water use as well as reduction waste generation and resource use can be used to help promote this concept further. 

Government regulations for example like those imposed in Singapore and Malaysia which requires new buildings to achieve a minimum green standard, if adopted locally, can help lay the foundation for the green building movement in Sri Lanka. 

[The writer is a Sri Lankan expert in the sphere of energy and green constructions. With Singapore as his headquarters for 25 years, Dr. Jayamaha earned the rare distinction of operating a series of energy and green construction projects in many countries across Asia. As the Founder and Chief Executive Officer (CEO) of LJ Energy of Singapore, he also serves as an accredited trainer of the Building and Construction Authority (BCA) of Singapore. He is the author of the book ‘Energy-efficient building systems’ published by McGraw-Hill in USA. He serves as the lead resource person at the green constructions management higher training courses organised by The Ceylon Institute of Builders.]