Design for Sustainability

Engineers have become very good at designing for operational feasibility - - which implies that a particular system will perform as intended in an effective and efficient manner for as long as necessary. We have accomplished this requirement with a total engineering design effort as outlined below:

• Design for Reliability - - Four elements are embedded in the concept of reliability. They are probability, satisfactory performance, time, and specified operating conditions. Reliability as an inherent characteristic of design, must be an integral part of the overall system engineering process.
• Design for Maintainability - - Maintainability is a design characteristic dealing with the ease, accuracy, safety, and recovery in the performance of maintenance functions. In an environment where resources are becoming scarcer, it is essential that system maintenance requirements be minimized and that maintenance cost be reduced.
• Design for Supportability -- System support is viewed as the composite of all considerations needed to assure the effective and economic support of a system throughout its life-cycle. Activities include maintenance planning, supply support, logistical support, training, facilities management, and computer/information management.
• Design for Economic Feasibility - - The focus must be on total system costs over the entire life-cycle from design cost to construction cost to operation/support cost to retirement/disposal cost - - future infrastructure systems will need to be planned, designed, produced, and operated under extremely limited fiscal constraints.

What then is "Design for Sustainability?" I would argue that the term is still in a state of flux - - where definitions and metrics are being considered, developed, and debated. Some elements of sustainability will interface directly and closely with the broad issues of reliability, maintainability, supportability, and economic feasibility. Other elements of sustainability will require new ways of thinking and professional cultural shifts. In general, a more holistic approach to design will be required, where the following elements will need consideration in the age of "Design for Sustainability" - -

• Climate Science and Change
• Moves Toward Increased Urbanization
• Energy Systems and Consumption
• Alternative Energy Sources
• Water Consumption
• Food and Agricultural Production
• Eco-Industrial Consideration
• Material Ecology
• Green and Net-Zero Buildings
• Public Transportation Systems
• System Interdependences
• Ecosystem Impacts
• Earth Systems Engineering