How Can Engineering Probability Help to Achieve Sustainability ?
What is Sustainability? Traditional definition Policies and strategies that meet society’s present needs without compromising the ability of future generations to meet their own needs. (Brundtland Commission, 1987) Public Policy Perspective Satisfaction of basic economic, social, and security needs now and in the future without undermining the natural resource base and environmental quality.
Sustainability Concept Humans are integral part of the natural world and nature must be preserved. Triple bottom line solutions Good for the environment Good for economics Good for society
Source: Bob Willard, The Sustainability Advantage. Typical business view Sustainability view Environment ECONOMY Society ENVIRONMENT Society Economy Mental Models
Triple Bottom Line The triple bottom line for business is one that protects the environment and improves the lives of the people whom that environment interacts with. A measure of success in terms of per capita, natural capital, and profit. The 3 Pillars People Planet Profit
Triple Bottom Line People Fair practices for all people and does not exploit interest of separate parties based on money, status or growth. Planet Management of renewable and non renewable resources while reducing waste. Profit Financial benefit enjoyed by the majority of society.
Sustainability and its Place in Business Cost-savings Corporate image and reputation Guidelines/directives from upper management Impact of legislation (“must do” factor)
Definition of Sustainability: Two Views Ford: “A business model that seeks to create value for stakeholders by preserving or enhancing economic, environmental and social capital.” Herman Miller: “Not doing business where it will harm future generations”, with the head of the Environmental Department adding that it’s also: “something that’s profitable….if we aren’t making money at this, we will be out of business. And then we won’t be doing anybody any good.”
Environmental Impact – How bad is it? How much waste do you think we generate? as individuals? as a society? from industry? How much CO 2 do you think a refrigerator produces? How much impact do you think computers have? Other examples?
Example: Refrigerator Impact In the course of its service life, an average three-star refrigerator consumes roughly 5,000 kilowatt-hours and produces about 2,400 kilograms of CO 2 (a greenhouse contributor). An assessment of the entire product line of a refrigerator - ranging from the extraction of raw materials to the disposal of the used product - shows that the lion’s share of this energy (90 percent or more) is consumed during the refrigerator's period of use.
Example: Computers & Energy Consumption If the number of workstation computers continues to grow as it has in the recent past, a new power plant will have to be built every five years in order to cover the increasing electricity consumption in Germany. While the computer’s specific energy consumption per processing transaction is decreasing, this development is offset by the greater computing power of the new machines.
Natural Resources Goods and Services Pollution, Waste and Environmental Disturbances Source: World Resources Institute Approximately 25% of what goes ‘in the pipe’ comes out as goods and services. Today’s Material Flow
Source: World Resources Institute Tomorrow’s Material Flow Reduce Use of Natural Resources Recover Technical Nutrients
Engineering Probability Tools Descriptive Statistics Probability Distributions Data Collection/Sampling Statistical Estimation Hypothesis Testing Regression and Analysis of Variance
Engineering Probability Approach to Sustainability For a given topic, students should be able to address the following questions: What are the issues that impact sustainability? What is currently known about these issues? What knowledge is needed to better understand how to achieve sustainability? What are potential factors and research questions? What data are needed? What are practical issues for collecting these data? How can probability and statistics tools be used to analyze the data?
Example: Groundwater Sustainability 50% of the U.S. depends on groundwater for daily drinking water. Sustainability Issues: Maintaining groundwater levels Keeping groundwater free of contaminants 
Groundwater Sustainability What is currently known about groundwater levels? Climate change is primarily quantified by a rise in the Earth’s near-surface air temperature. The rise in temperature will cause glaciers, ice sheets, and snowcaps to melt, causing added runoff into oceans. The runoff into oceans will increase sea level. The primary sources of fresh water (glaciers, etc.) will be reduced. Fresh ground water supplies at coasts could be contaminated by salt water from oceans.
Groundwater Sustainability What are sources of groundwater contamination? Surface water contamination and runoff. Combined sewer/stormwater systems that overflow during significant storm events. Malfunctioning or leaking septic systems, lagoon systems, centralized wastewater treatment systems. How does nature prevent contamination? Native shrubs, perennials, flowers absorb water and filter out contaminants. Trees, shrubs, and grasses can form buffers to protect clean water sources.
Groundwater Sustainability What knowledge is needed? Potential factors? Can we detect potential sources of contamination? Monitor fresh water supplies. Can we mimic nature? Study porous pavements (e.g., Cowboys Stadium). Can we develop a cost-effective desalination process to convert salt water to fresh water? Study existing desalination processes and costs. Can we avoid sewer/stormwater system overflows? Study the causes of combined sewer/stormwater overflow.
Groundwater Sustainability Data? Issues? To monitor fresh water supplies, collect field data. Issues: There a lot of places to monitor. Need to specify the metrics to quantify water quality. To study porous pavements, collect data on the permeability of various pavements and their ability to filter out contaminants. Issues: Need to specify runoff conditions, such as the amount and the level/type of contamination.
Groundwater Sustainability Data? Issues? To study desalination, collect data on the energy needs of various processes. Issues: It may be difficult to gain access to data. Need to specify the salinity of the influent water. To study sewer/stormwater system overflows, collect data on storm events and overflow. Issues: Need to specify the metrics used to describe a “storm event” (e.g., amount or rate of precipitation) and the severity of an overflow (e.g., amount or rate). Need to be able to measure these metrics.
Groundwater Sustainability How can probability and statistics tools be used to analyze the data? Use plots to track water quality. Use two-sample tests to study different pavements, such as two-sample tests on filtration percentages. Develop a regression relationship between the cost of desalination and the salinity of influent water. Fit probability distributions to storm event data. Estimate the probability of such events leading to combined sewer/stormwater system overflows.
Topic 1: Transportation Systems Emissions from vehicles have been cited as major contributors to greenhouse gases and land use. Sustainability Issues: Air pollution Land use Telecommuting 
Transportation Systems What is currently known? Public transportation consumes less energy and uses land more efficiently than private transportation. Public transportation is accessible to all members of society. Public transportation encourages cities to grow more compactly. Telecommuting replaces the daily work commute with telecommunication links. Adding HOV lanes reduces vehicle traffic.
Transportation Systems How do transportation systems impact pollution? Vehicle emissions are one of the leading contributors to air pollution. Adding HOV lanes reduces vehicle traffic. Under-utilized public transportation systems fail to reduce vehicle traffic. Idling, acceleration, and deceleration of vehicles contributes higher emissions per mile traveled. Cars are most fuel efficient at 40-60 mph. Disposal of old vehicles is not sustainable.
Topic 2: Cleaner Energy Alternative energy sources are critically important for curbing greenhouse gas emissions and creating a more independent energy economy. Sustainability Issues: Renewable energy Electric vehicles Biodiesel 
Cleaner Energy What is currently known? Our present fuel resources are mostly made up of fossil fuels, which are not considered renewable. (The world’s consumption of fossil fuels is 100,000 times faster than their natural production.) The combustion of fossil fuels releases air pollutants. Renewable energy sources are naturally renewable, such as solar, wind, hydropower, and geothermal. In 2010, only a small portion of electricity generation, about 18%, was from renewables. Renewables have high variation and higher cost.
Cleaner Energy What are alternatives for vehicles? Biodiesel is a mixture of diesel and biomass from plant oils, animal fats and even recycled grease, and can reduce vehicle emissions of greenhouse gases by 75%, but the cost-effectiveness of biodiesel processes is still unclear. Diesel vehicles can directly use biodiesel blends without any engine modifications. Battery electric cars have zero tail pipe emissions, but their battery storage still needs improvement. Hybrid gas-electric cars can improve fuel-efficiency, but require special engines.
Topic 3: Logging The U.S., with less than 5%of the world's population, consumes 17% of the world's output of timber and is the third largest importer of tropical timber. Sustainability Issues: Deforestation Forest biodiversity Pulp/paper production 
Logging What is currently known? The forest products industry is a large part of the economies in developed and developing countries. Wood is considered a renewable resource. The primary material for making paper is wood pulp. Alternatives include recycled pulp and field crop fiber. Wood is also used for construction and is hard to replace.
Logging What is known about deforestation? Deforestation is one the major contributors to global warming. Deforestation disturbs the water cycle (i.e., rainfall) and increases soil erosion. Reforestation replenishes forests, but can diminish biodiversity. Tropical deforestation is still a problem. The restriction of trade in certain species is enabled by listing with CITES(the Convention on International Trade in Endangered Species of Wild Flora and Fauna), but this is still controversial.
Topic 4: Fisheries The global fishing fleet is estimated to be 250% larger than what the ocean can sustainably produce. Sustainability Issues: Overfishing Ocean conservation Food supply 
Fisheries What is currently known? Fish currently supply the greatest percentage of the world's protein consumed by humans. Seafood guides help consumers make informed choices. Fish farming, an alternative to sea fishing needs more development. Management of ocean ecosystems as a whole is needed, including prohibiting fishing in certain zones. Management requires communication between national governments and markets.
Fisheries What is known about overfishing? Depleted fish stocks can be restored only if the species' ecosystem remains intact. Overfishing disturbs the life cycle (food web) of aquatic flora and fauna. Overfishing and by-catches made during fishing may result in depletion of certain species, leading to possible extinction and a reduced food supply for predators. Advanced technologies have contributed to overfishing.
Topic 5: Waste Management In 2006, U.S. residents, businesses, and institutions produced approximately 4.6 pounds of waste per person per day. Sustainability Issues: Landfills Recycling Bioreactors 
What is currently known? Reuse, recycle, reduce, recover. Landfill mining and reclamation (LFMR) is a process whereby solid wastes that have previously been landfilled are excavated and processed. Landfills are monitored to minimize groundwater contamination. Methane from landfills is a natural energy source. The decomposition of plastics takes about 1000 years. Landfills occupy land that could be used for other purposes. Waste Management
What are bioreactors? Bioreactors use moisture to enhance the waste degradation process, but more research is needed to design safe bioreactor landfills. Different biological process are performed to decompose different types of waste. Different types of waste (e.g., recyclables, food, textiles, drugs, e-waste) can be treated more efficiently if separated, but this is a difficult to achieve in practice. Waste Management
Topic 6: Green Building Buildings account for a large amount of land use, energy and water consumption, and air and atmosphere alteration. Sustainability Issues: Environmental Impact Life Cycle Cost Sustainable Design 
Green Building What is currently known? Green building typically costs more to implement, but costs less to maintain, and is more economical over the entire life cycle (cradle-to-grave). There are already many green building guides (e.g., LEED in U.S., BREEAM in U.K., Green Star in Australia). Green building uses non-toxic recycled materials and rapidly renewable plants (like bamboo), and seeks to reduce waste during construction.
Green Building What are the impacts of green building? Reduced energy usage via solar energy, insulation, high-efficiency windows, natural lighting/shading. Reduced water usage via on-site water treatment or a greywater system for irrigation. Better indoor air quality improves human health. Reduced waste generation.