How Can Operations Research Help to Achieve Sustainability ?

1. How Can Operations Research Help to Achieve Sustainability ?

2. Operations Research I Tools Linear Programming Integer Programming Goal Programming Network Analysis Dynamic Programming Nonlinear Programming

3. Operations Research I Approach to Sustainability By the end of this unit, for a given topic, students will be able to address the following questions: What are the issues that impact sustainability? What is currently known about these issues? What are relevant objectives for sustainability? Do we want to minimize, maximize, or meet a target? What are possible actions to achieve sustainability? What are practical issues and constraints for implementing these? How can operations research tools be used to guide more sustainable decisions?

4. 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 [3]

5. 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.

6. 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.

7. Groundwater Sustainability What are relevant objectives for sustainability? Minimize contaminants in groundwater. Maintain the supply of fresh water. Minimize runoff. Minimize overflow from combined sewer/stormwater systems. Maximize use of natural habitats and native plants. Minimize life cycle economic cost.

8. Groundwater Sustainability What are possible actions to achieve sustainability? Practical issues? Constraints? To reduce contamination from malfunctioning systems, implement a maintenance program. Issues: Need regulation or economic incentives to implement such a program. To reduce runoff, use porous pavements that mimic nature (e.g., Cowboys stadium) or rain gardens that use native plants. Issues: Need to study the choices relative to the situation and consider cost.

9. Groundwater Sustainability What are possible actions to achieve sustainability? Practical issues? Constraints? To maintain the supply of fresh water under the effects of climate change, consider desalination. Issues: Desalination is currently not cost-effective. To reduce the impact of sewer/stormwater overflow, keep fresh water supplies upstream or use trees and shrubs as buffers or re-design these systems. Issues: The appropriate choice depends on the location and incidence of overflows.

10. Groundwater Sustainability How can operations research tools be used to guide more sustainable decisions? Use dynamic programming to optimize a system’s maintenance plan over time. Use integer programming to select among various choices for a given situation. Use network analysis to study the network of groundwater sources and their potential for contamination. Use goal programming to design a cost-effective desalination process.

11. 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 [4]

12. 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.

13. 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.

14. 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 [5]

15. 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.

16. 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.

17. 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 [6]

18. 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.

19. 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.

20. 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 [7]

21. 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.

22. 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.

23. 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 [8]

24. Waste Management 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.

25. 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.

26. 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 [9]

27. 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.

28. 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.