How Can Operations
Research Help to Achieve
Sustainability ?
Operations Research I Tools
 Linear Programming
 Integer Programming
 Goal Programming
 Network Analysis
 Dynamic Programming
 Nonlinear Programming
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:
1. What are the issues that impact sustainability?
What is currently known about these issues?
2. What are relevant objectives for sustainability? Do
we want to minimize, maximize, or meet a target?
3. What are possible actions to achieve sustainability?
What are practical issues and constraints for
implementing these?
4. How can operations research tools be used to
guide more sustainable decisions?
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]
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 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.
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.
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.
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.
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]
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
[5]
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
[6]
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
[7]
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
[8]
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.
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.
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]
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.