Doing More with Less

1
Doing More with Less!
Engineers Without Borders November 2, 2005

• Ty Newell
• Department of Mechanical and Industrial
  Engineering
• University of Illinois at Urbana-Champaign

2
Our Needs are Simple

• But, obtaining these things are dependent on a
  complex network of factors
• A common denominator is energy
• Processes utilizing energy must be efficient
  (reversible)
• Resources supplying energy must be sustainable

3
Economic Viewpoint
Must have Money In gt Money Out

• Recycling Example
• 150/ton to collect and process recyclables
• 120/ton revenue for sales of recyclables
• Net cost 30/ton
• Landfill cost 30/ton
• Which is better???

Your Community, Country, Continent
Money In
Money Out
4
Economic Viewpoint - Optimal Design

• Costs are totaled over a systems lifetime
• A design is desired that minimizes the total cost
  (or, alternatively, maximizes profit)

Operation Cost Dominated
Capital Cost Dominated
Total Cost
Cost
Capital Cost
Operation Cost
Insulation Thickness Pipe Diameter Etc.
5
Economic Viewpoint

• The optimal solution depends on the lifetime
  assumed
• A short lifetime reduces the impact of energy
  (operational) costs on the optimal solution
• Most decisions are made based on short lifetimes

Locus of optimal solutions based on lifetime
energy use
Cost
Insulation Thickness Pipe Diameter Etc.
6
Value of Energy
Our perception of energy is poor.
100 mph baseball (1/2 kg) 1¼ kJ/kg 0.75
kJ (50 m/s)
1 U.S. Hairdryer (1500 W) operated for 1
second 1.5 kW x 1sec 1.5 kJ

• Therefore, being hit in the head with two
  fastballs in one second is equivalent to running
  a hairdryer for 1 second!

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Value of Energy
Inflating a balloon requires 3 Joules of work

• At 0.10/kW-hr (typical US cost), 1 could
  inflate 10,000,000 balloons

A small amount of energy can do a lot when mixed
with intelligence and creativity.
8
The Lie

• Natural gas
• Last year, 5/MMBtu
• This year, 15/MMBtu!!

• Many would have you believe that renewable energy
  can only provide a small fraction of our energy
  needs
• Short term viewpoints make energy cost variations
  painful and destabilizing (economically,
  security)
• We do not need more energy supply
• We need to reduce energy demand
• Energy conservation and efficiency provide jobs
• Oil consumption buys bullets

9
US
Since 1950.....

• The US has released 186 billion tons of carbon
  dioxide
• India has released 16 billion tons of carbon
  dioxide
• The depth of CO2 produced by the US would be 10.3
  meters over the land area of the US
• The depth of CO2 produced by India would be 2.4
  meters over the land area of India

INDIA
10
Is Our Future Bright?
Given that

• We have made significant gains in solar energy
  processes, but have yet to see widespread
  commitment to implement them
• No noticeable commitment to move away from fossil
  fuel and other non-sustainable energy dependence
• Lack of significant commitment to reduce energy
  consumption of conventional processes

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Yes, Our Energy Future Can Be Bright!
Because

• 25 years ago, we could not have imagined a
  computer in every office
• 25 years ago, we could not have imagined
  communicating between around the world by e-mail
• 25 years ago, we could not have considered
  common, everyday usage of lasers,
  microprocessors, microsensors, rapid
  prototyping, CAD-CAM, and a wide array of new
  materials manufacturing processes

• And, we cannot imagine 25 years from now, but we
  can help build the path taken.

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Some things are improving ...

• Average US cost (800-1300)
• 20-26 ft3 (560 to 740 liters)
• 500 to 1050 kW-hr/year

13
Energy Consumption

• Refrigerators continue to improve, leading to
  significant reductions in energy requirements
• No single solution, many small, cumulative
  improvements required

14
Environmental Effects

• Reduction of energy consumption benefits the
  environment, too
• Changes in cabinet design, refrigeration system
  design, and refrigerants have reduced global
  warming effects
• Improved cradle-to-grave design for component
  recycling

15
Environmental Effects

• At its peak, US refrigerators accounted for 3
  of annual CO2 releases
• By 2010, refrigerators should be lowered to 1
  of CO2 released assuming no energy improvement in
  other sectors

16
Many Significant Gains in Solar Energy Utilization
wind
photoelectronic
desalination

• Processes
• Systems
• Basic phenomena
• Materials
• Analysis
• Optimization

ocean energy
photochemical
instrumentation
photosynthesis
concentration
solar thermal
biomass
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So Why do We Still Need These?
18
Vehicle Energy Use

• We continue to develop and use inefficient energy
  processes.

• 1962 Chrysler Imperial
• 4600 pounds (2100 kg)
• 340 horsepower
• 8 mpg (4 km/liter)

• Vehicles are not designed to transport
  humans...they are designed to transport the
  vehicle.

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Vehicle Efficiency
From SAE Supermileage Competition

• A 1.5 hp engine should be able to move a
  streamlined human at 60 mph and 1500 mpg (750
  km/lt)

• If 10 of our vehicles have 57 mpg, our 26mpg
  fleet average would increase to 29mpg (12)

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Pump/Fan Flow Control

• We continue to control processes inefficiently

System flow curve
Effect of valve opening/closing
Operating point
Typical centrifugal fan/pump flow curve
21
Agriculture

• Every square meter of ground is scratched,
  gouged, crushed, sprayed, irrigated, and
  fertilized whether needed or not

• Why not an army of small, solar powered robots
  with sensing, intelligence, and actuation
  capabilities to care for crops as needed?

22
We Do Not Recycle

• Aluminum
• 70 therms/ton to reprocess
• 1830 therms/ton for virgin
• 1.5 tons waste/ton for virgin

• Paper
• 160 therms/ton to reprocess
• 720 therms/ton for virgin
• 1.8 tons waste/ton for virgin

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CU Garbage

• We have 700 tons of aluminum cans and 50,000
  tons of paper with less than half recycled
• Recycling 700 tons of aluminum would conserve
  1,200,000 therms of energy per year
• Recycling 50,000 tons of paper would conserve
  28,000,000 therms of energy per year

• CU has 38,000 residences
• Winter heating requires 2400 therms/residence
• Recycling 100 aluminum and paper would heat
  12,500 residences (if homes were properly
  constructed, all of CU residences would be heated)

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Comfort

• Houses are poorly insulated
• Comfort conditioning systems are inefficient
• Lighting is inefficient

• A typical house in the midwest region of the US
  requires 400 MJ/day for heating when 0C outside
• But, approximately 1000 MJ of solar energy falls
  on the house during the day, essentially unused

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Transient Building Effects

• Zero energy design requires simulation analyses
  of heat and mass (moisture) transfers
• Insulation
• Window area
• Thermal mass

mass
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Comfort Conditioning

• Conventional
• UA700kJ/hr-K
• mc10,000kJ/K
• Awind20m2
• Advanced
• UA250kJ/hr-K
• mc20,000kJ/K
• Awind30m2

We can build energy efficient, comfortable
dwellings
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We are in an exciting time!

• A playground of new things allowing us to create
  and invent
• New ways to sense, decide, and actuate
• New materials
• New processes

• We must remember that the seeds we sow today may
  not be important for today

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Thank You!
But, given time, our efforts can grow