Post on 23-Feb-2016
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The Electric Boat Challenge:
Is Solar Power Better than Gasoline Power?
Or does H2 Work Best?
Dr. Andrew Zborowski, Ph.D.and Frank R. Leslie, BSEE, MS Space Technology
1/14/2005
1. Abstract• Identical trolling
motors• Similar hulls• Identical batteries• Differing energy
sources• What is to be
demonstrated?
What speeds and distances result from solar & gasoline, etc. sources?
AbstractSolar
Gasoline
2. Hull Forces• Drag force is
proportional to speed squared
• Drag force is balanced by motor force resulting in equilibrium speed
• Different hull shapes result in different maximum speeds
Speed limited by forces
Hull ForcesFh = k • S2
Fm = Fh
Fm FhMoving this way -->
3. Motor Thrust• Measure thrust force
with “open water” around prop (bollard test)
• Plot relationships• Compare motors• Specification of 30
pounds thrust
What is “best” load?
Motor Thrust
Fm
Load Resistance
Force,Current
Voltage
4. Travel Energy• Energy =
Power • time• E = P • t• Define race end• Define time &
distance V = d/t
What energy is required?
Travel Energy
Distance, d
5. Energy Storage• Battery depletion rate• Are batteries truly
identical?• Full charge at 12.80
volts (TBR; to be reviewed)
• Discharge load of motor affects available ampere-hours
• Stop at 10.5V to preserve battery life Trade power vs. energy
Energy Storage
10.5 VVoltage,
E
Time, t
= ?
6a. Energy Sources• Internal Combustion
Engine (ICE) burning gasoline and oil mix charges battery– Requires fuel
• Solar Panel charges battery– Requires sun
What else to use?
Energy Sources
Solar or PV
Gasoline ICE
Gasoline
Crudeoil
6b. Energy Sources• Fuel Cell
– Hydrogen & air in– Water & Electricity out– ~12Vdc; 1000 watts
• Leslie’s Pedal Cycle – Requires food in– Biomass to mechanical
to electrical energy– 14 volts @ 6 amps
charges battery
Which to use?
Energy Sources
Pedal Cycle
Hydrogen Fuel Cell
Hydrogen
FuelCell
12Vdc
7. Race Conditions• Ready to race?
– Good weather– Calm water– Wind below 4 knots– Batteries charged– Known weight– Straight, sheltered course– Side-by-side start– End defined by battery
voltage less than 10.5 volts per digital multimeter or H2 tank empty
Perhaps a little slower
Race Conditions
8. Potential Conclusions and Findings• Match results against
theory– Explain discrepancies
• Data analysis shows that . . . ?
• Recommendations for the following classes --- “Lessons Learned”
• Create report and present results
What’s next?
Potential Conclusions and Findings