Sustainability in Engineering Design

Sustainable development is a concept to develop a possible sustainable living for the modern society. There are several definitions to the concept of sustainable development. World Commission on Environment and Development (WCED) published one of the definitions that have been used widely up to date in 1987. Gro Harlem Bruntland, the chair of WCED in 1987, defined it as:

“Development that meets the needs of the present without compromising the ability of future generations to meet their own needs”.

The Bruntland’s definition is concise and covers the requirement to satisfy intergenerational needs. The definition is based on two concepts:

* The concept of needs, comprising of the conditions for maintaining an acceptable life standard for all people, and

* The concept of limits of the capacity of the environment to fulfill the needs of the present and the future, determined by the state of technology and social organization.

However, this also has wild range of different interpretations. It has been considered that it fails to include limits within which society must operate. Therefore a more contemporary definition was developed by the NGO.

“Sustainable development is a dynamic process, which enables all people to realize their potential and to improve their quality of life in ways which simultaneously protect and enhance the Earth’s life support systems”

The NGO’s definition emphasis the importance of social justice and it intended to balance the environmental, social and economical aspects in order to improve the quality of life. The definition is delivering the following concepts.

* Built development that sustains life and improves the quality of life for human beings;

* Limits the environment’s ability to meet present and future needs, protect the environment;

* Work that removes the environmental and/or social damage from the past and improves the sustainability of the wider environment and ecosystems;

* Using minimum Earth’s resources for maximum achievements in life quality;

* Conserving resources and minimizing waste;

* Safeguarding and maintaining mutual respect with people

Various roles and practical actions need to be taken by the many disciplines, organizations and individuals involved in delivering the challenges of sustainable development. These include delivering poverty reduction, environmental protection and enhancement, efficient use of natural resources, an improved built environment, economic growth and stability, and enhancing social capital and human well being. The role of professional civil engineers is not simply about ameliorating environmental damage of construction, we can and do positively improve the human world through the provision of water supply, wastewater treatment, power stations, roads, airports, ports, bridges, canals etc. Any civil engineering project that ignores sustainability or does not seek to deliver more-sustainable solutions will be considered as an incomplete engineering practice.

Protecting the Environment

As the world’s technology is increasing, this will also increase the life expectancy and life quality within the modern society and hence an increase in world’s population. However, engineers will be required to review on the needs of the community to provide a suitable sustainable plan of action. In the past century the quality of life and the population have been increased enormously comparing to the past centuries. In order to increase the living standard, electricity is playing an essential role. Modern electricity generation mostly from burning of fossil fuels, therefore access of ‘clean’ energy is essential in reducing the emission of greenhouse gases into the atmosphere.

The mean of improving in life quality is related to the decrease of the Earth’s natural resources and the climate change. With the amount of greenhouse gases such as carbon dioxide and methane present in the atmosphere can trap heat and cause an increase in global average surface temperature. This will also increase the global average sea level. Communities in low-lying areas will be the most affected, and the change in the precipitation patterns and the availability of water resources will have consequences for economic and social welfare of mankind. The climate change should not be a problem to the Earth as the carbon dioxide is an essential element for the plants and forests, but due to the deforestation in developing countries, an excessive amount of carbon dioxide will be remained in the atmosphere.

Emission of greenhouse gases is the primary problem leading to the climate change. However, the greenhouse gas concentrations are related to the economic growth and the energy use. This link will need to be broken and the carbon intensity of most activities will need to be substantially reduced. Introducing clean energy methods will be helpful in reducing the greenhouse gas concentrations in the atmosphere. There are three main options for clean energy: renewable, nuclear and fossil fuels with carbon sequestration. Renewable and nuclear energy are considered to be environmental friendly, as they don’t use up any of the Earth’s resources. The renewable energies include solar, wind and waves etc.

The nuclear energy is the cleanest energy out of all, but because of the problems associate with radioactive waste storage, safety and decommissioning, hence the future role of nuclear energy is uncertain. As the amount of fossil fuels are shorting, there is a new method that is being introduced that using pure hydrogen left by the fossil fuels while the carbon dioxide elements are stored in underground reservoirs. Such method is likely leading to renewable based electrolysis production methods.

In the project design stage the designer should explore environmentally friendly and sustainable features and for incorporation with their proposals. The following environmentally friendly and sustainable features will be considered:

* Energy efficiency and renewable energy such as minimization of electric load from lighting, appliances and equipment;

* Direct and indirect environment aspect such as air and water pollution arising from operations;

* Resource conservation and recycling such as use of recyclable products;

* Indoor environmental quality such as volatile organic compound content of building materials;

* Community issue such as climatic characteristics that after the use of building materials

Sustainable Building Design

Sustainable building is the future of construction. It takes into consideration the total environmental and economic impacts. The concept of sustainability in development is based on principles of resource efficiency, health and productivity. These principles require that we look at buildings, energy sources and development on a full, life-cycle basis. This approach takes into consideration the total environmental and economic impacts, energy sources, performance from material extraction, product manufacture, transportation, design and construction, operations and maintenance, building reuse or deconstruction and disposal.

Sustainable building is comprehensive and provides valuable long-term economic and environmental benefits. These buildings are designed to produce less greenhouse gases while being more comfortable, healthy and economical through the proper application of sustainable design principles. Great advances have been made possible by the coordination of architectural design and technology. The construction of such sustainable buildings consume less fossil fuel, limit environmental impacts, and improve worker health and productivity.

In the sustainable building design it is often to have some kind of features for energy saving. One of the energy widely used is for lighting. However, while designing the sustainable building it is essential to have designed the lighting systems. The sustainable designers often use the natural daylight to shine into the building as part of lighting system for energy saving during the day time. There are a few day lighting strategies that are commonly used: top lighting, side lighting and core lighting. By using such lighting strategies glass fittings for the roofs and walls will be installed. Such arrangements will be energy efficient as it not only save energy for the lighting, but also for heating, ventilating and thermal storage.

The excessive heat within the building will be stored or vented. The building is also designed for water heating and air conditioning by solar energy, and improving the air quality. The major factors that are contributing to indoors air quality are shown in fig.1 below. The sustainable building design is economical and environmental friendly that it uses renewable energy for lighting and for air conditioning etc, that it will save a lot of operational energy and it will not increase the greenhouse gases concentrations in the atmosphere. Hence such building design can reduce the electricity usage and reduces the amount of greenhouse gases emitting into the atmosphere.

Fig.1 – Major Factors Contributing To Indoors Air Quality

The International Netherlands Group (ING) bank headquarters in Amsterdam was one of the first of Europe’s celebrated large sustainable buildings. It is largely daylight, highly energy efficient, and architecturally innovative with such features as curvilinear form, local materials, plants, artwork, and flowing water incorporated into the building in a highly integrated fashion.

At the designing stage the board’s requirement was refined by the planning and design team with the following three criteria: ‘First, the building must be thoroughly functional using the latest technology, including a specially designed security system and options for individual climate control. Second, the building had to be flexible, able to respond to inevitable changes in space needs over time. Third, the building had to be energy efficient, yet not cost “one gilder more” than conventional construction.’ The designer laid out a strategy to deliver a functional cost-effective new headquarters that would be both appealing and environmentally responsive in design and function in order to meet the above objectives.

The building does not use conventional air conditioning, relying primarily on passive cooling with back-up absorption chillers. This sustainable building uses less than a tenth the energy of its predecessor and a fifth that of a conventional new office building in Amsterdam. The annual energy savings are approximately 2.9 million U.S. dollars, and the construction cost of the building was paid back in three months after the opening.