Alternative Energy Propulsion in
Short Route Ferries
Case Study: Halifax Harbour Ferries
Presented By:
E.Y.E. Marine Consultants
What is meant by “Alternative Energy”?
Hybrid
Green Energy
Reducing Emissions
But Does it Pay?
What we Are Comparing?
Diesel Propulsion vs.

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Diesel Engines
Main source of
power from
diesel fuel
No secondary
sources of
power
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Battery
Battery
Powered
Main source of
power from
Battery Bank
No secondary
sources of
power
Plug into
electrical grid
during stops
and over night
vs.
Hybrid
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Diesel Electric
Main source of
power from
Battery Bank
Secondary
sources of
power from
diesel
generator
Plug into
electrical grid
during stops
and over night
Energy Density
12000
Diesel, 10400
10000
Wh
8000
6000
Engine Generated
power, 4160
4000
2000
Li-Ion, 163
Lead Acid, 20
0
1 Litre
So Why bother?
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Consider ferry uses 15L/Trip of fuel
Ferry operates 67 trips a day
That’s 1005 Litres of Diesel Fuel per day.
@ $1/L that’s $1005/day
Total Savings of $503.30/day
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Amount of energy used per day
1005L x 10.4 kW-h/L = 10452 kW-h/Day
Diesel engine operates at approximately 40%
efficiency = 10452 x .4 = 4180.8 kW-h/Day
Average rate of power from NS power is
$0.12/kW-h
Total operating cost = 4180.8 x 0.12 = $501.70
Let’s look at Batteries
Lead Acid
(AGM)
Lithium Ion
Nominal Voltage
2.0V
3.70V
Energy Density
20 Wh/kg
163 Wh/kg
~3000
(8 yrs.)
~300,000
C/5
2C
$0/ Life time
$0/ Life time
Installation
Cost
$20 /kW-h
$1600 /kW-h
Recyclable
Yes
Yes
Cycle Life
(50% DOD)
Charge Capacity
Pack
Maintenance
Battery Propulsion
Rate of Power Consumption
12000
10000
kW-h
8000
Rate of Consumption Diesel
6000
Battery Capacity
4000
2000
0
1 6 11 16 21 26 31 36 41 46 51 56 61 66
# Trips
Total Required Capacity:
Diesel = 10451 kW-h
Battery = 2626 kW-h
The Breakdown
Total Power Used = 4238 kW-h/Day
Total Rechargeable Power = 1620 kW-h/Day
Available Regeneration Rate
600V x 250Amps = 150 kW
Off Hours Recharge required = 2625 kW-h/Day
The Good
Daily Savings
Savings/Day
Co2 Emission Saved
Yearly Savings
Savings/Year
Co2 Emission Saved
$689.94
2.49 Ton/day
$137,287.57
907.06 Tons/yr
The Bad
Actual Battery Capacity Needed:
AGM = 6562.5 kW-h
Li-Ion = 4375 kW-h
Installation Cost:
AGM = $ 131,670.00 (@ $20/kW-h every 8 years)
Li-Ion = $ 7,000,000.00 (@ $1600/kW-h Life time)
Over 30 yrs.
Diesel Power
Engine Costs
Maintenance
Fuel
Total
$235,000.00
$609,039.00
$6,000,000.00
$6,844,039.00
AGM Power
Install Costs
Maintenance
Energy Costs
Total
$493,762.50
$0.00
$1,881,372.86
$2,375,135.36
Li-Ion Power
Install Costs
Maintenance
Energy Costs
Total
7,000,000.00
0.00
$1,881,372.86
$8,881,372.86
The Ugly
Actual Battery Size Needed:
AGM = 321,125 kg or 87.5 m^3
Li-Ion = 26,840 kg
or 13.7 m^3
The Ugly Cont’d
Charging Constraints:
600V x 250 Amps = 150 kW
Max. Charge Off Duty
150 kW x 6 Hours x 2 chargers = 1800 kW-h
We Require 2625 kW-h
Now Where?
What are the things we need to change?
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Need to reduce the Battery Bank
Size.
Reduce the Battery Bank Capacity.
Reduce the installation costs for
the battery bank.
SOLUTION?
HYBRID!
Hybrid Propulsion
Battery Capacity
1800
1600
1400
kW-h
1200
1 Generators
1000
2 Generators
800
3 Generators
4 Generators
600
400
200
0
0
5
10
15
20
25
30
35
# of Trips
40
45
50
55
60
65
The Breakdown
1 Generator:
Required Battery Capacity = 1660 kW-h
Installed Capacity:
AGM = 4150 kW-h
Li-Ion = 2667 kW-h
2 Generators:
Required Battery Capacity = 1000 kW-h
Installed Capacity:
AGM = 2500 kW-h
Li-Ion = 1667 kW-h
30 Year Cost Comparison
Diesel Power
Engine Costs
Maintenance
Fuel
Total
1 Generator
AGM Power
Install Costs
Engine Costs
Maintenance
Fuel
Total
Li-Ion Power
Install Costs
Engine Costs
Maintenance
Fuel
Total
$235,000.00
$609,039.00
$11,004,750.00
$11,848,789.00
2 Generators
$312,246.00
$75,000.00
$214,839.00
$6,341,825.00
$6,943,910.00
AGM Power
Install Costs
Engine Costs
Maintenance
Fuel
Total
$188,100.00
$150,000.00
$429,678.00
$9,277,193.03
$10,044,971.03
4,426,666.67
75,000.00
214,839.00
$6,341,825.00
11,058,330.66
Li-Ion Power
Install Costs
Engine Costs
Maintenance
Fuel
Total
2,666,666.67
150,000.00
429,678.00
9,277,193.03
12,523,537.69
The Physical Restrictions
Actual Battery Size Needed:
AGM = 207,500 kg or 53.3 m^3
Li-Ion = 16,973 kg
or 8.7 m^3
Li-Ion Only Solution
The Good and Bad
The Good
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30 yr. Savings of
$ 790,458.40
Emission Savings of
CO2 = 360.5 Tons/yr
Nox = 5.96 Tons/yr
Less exposed to
fluctuations in fuel
prices
The Bad
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More exposed to
fluctuations in
electricity prices.
Still very high
installation Costs
Additional costs for
charging
infrastructure
required at dockside.
From Here?
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Further analysis required into ferry
operating loads.
Further study into optimal generator size
and quantity.
Discuss possible safety issues with
regard to stored battery capacity.
Look for better battery technology to
improve energy densities.
Determine Charging infrastructure
requirement and cost at dockside.
Collect firm data with regards to
purchasing bulk energy and off peak
recharging.
Conclusion
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Technology is viable today with modest
savings.
Further savings possible with
development of emission credits.
Government incentives to promote and
off set large installation costs.
Further reduction in price with bulk
purchases of power and off peak
recharging.
Satisfaction of saving emissions and
helping environment.
For a copy of this presentation please visit our latest
news section at our website: www.eyemarine.com
E.Y.E. Marine Consultants
Suite 1, 327 Prince Albert Road
Dartmouth, Nova Scotia, Canada
B2Y 1N7
Phone: (902) 463.8940
Fax: (902) 463.6319
Email: eye@eyemarine.com