BAHAMAS ELECTRICITY CORPORTATION

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POWER GENERATION
IN
THE BAHAMAS
2011 ENERGY CONFERENCE
Miami Beach
23rd – 25th October, 2011
THE BEGINNING
It was formed out of the Electrical Department
which had its beginnings 104 years ago in
1907.
 Development was very mild UNTIL

CASTRO CAME TO POWER AND CUBA WENT
COMMUNIST
 American tourist trade shifted to The Bahamas

ECONOMIC DEVELOPMENT. (NEW PROVIDENCE)
The 1960’s saw very rapid, economic
development first with hotels and local
entertainment, taxis, local culture craft then
merchants shops with special tax-free items
designed to attract more tourists. Items such
as watches, perfume and jewelry.
 The economy flourished with many persons
holding two well paying jobs
 The demand for power GREW rapidly

POWER DEVELOPMENT (NEW PROVIDENCE)
Prior to the 1960’s all power generation was by
medium speed four stroke diesels burning #2
diesel.
 The beginning of the 1960’s saw the
commissioning of a steam powered station
burning a #6 fuel oil
 In 1963 Sulzer commissioned the first ever
land based slow speed two stroke diesel
generator also burning #6 fuel oil.

POWER ISSUES (NEW PROVIDENCE)

Rapid demand growth quickly out stripped
supply and the BEC was unable to meet the
demand resulting in one hotel being given the
concession to install generation to meet a part
of its load requirements. This they did with a
total energy plant based on diesel engines with
a combined thermal efficiency in the mid-80%
compared with straight run diesels of only 30%.
POWER ISSUES (NEW PROVIDENCE)
The high demand for power resulted in
maintenance staff working 24 hours to meet
the demand and the maintenance
requirements of the many medium speed four
stroke diesel engines.
 Manpower costs was a major corporate
expense.

POWER SOLUTION (NEW PROVIDENCE
High maintenance manpower costs, low fuel
costs combined with the need to rapidly install
additional generation was a classic fit for
combustion turbines burning #2 diesel oil.
 In the late 1960’s the BEC committed to
installing four combustion turbines the first of
which was installed in 1971.

NEW POWER ISSUE
Then in 1973 the Arab oil embargo turned
every thing upside down.
 The major expense was no longer manpower
costs, it was energy costs
 The purchased combustion turbines were
operating at efficiencies of only 20%!
 Fuel costs were driving the corporation deep
into debt.

GRAPH TELLS IT ALL.
WHAT WAS THE ANSWER?
?
BAHAMAS POWER DEMOGRAPHICS
The Bahamas Electricity Corporation serves
communities on 16 separate island groups
using 26 separate generation facilities!
 The islands cover an area roughly the size of
Florida so there is no interconnection because
of the large distances between them.

DEMOGRAPHICS
ISLAND
POPULATION
ISLAND
POPULATION
Abaco
17,000
Inagua
911
Andros
7,500
Long Island
3,000
Bimini
2,000
Mayaguana
270
Cat Island
1,500
New Providence
250,000
Crooked Island
323
Ragged island
70
Eleuthera
8,000
Rum Cay
99
Exuma
7,300
San Salvador
930
REGIONAL RELEVANCE
The Bahamas Electricity Corporation serves 26
island communities on 16 islands spread
across an area roughly the size of Florida
 Yet it is in the top ten with the lowest $/kwh in
the Caribbean, a region with 22 members in
the regional electric power association
(CARILEC) The majority of these member
countries are only one or two land masses.

HOW DOES IT DO THIS?
?
THE ANSWERS TO BOTH QUESTIONS ARE:
FUEL OIL
And
 LOW SPEED TWO-STROKE DIESEL ENGINES

GENERATION CAPACITY




All electrical generation in The Bahamas is thermal,
using either a #6 residual fuel (RMG35) or a #2 gas
oil (DMB)
There is a total installed electrical generation capacity
of 450 Megawatts.
350 Megawatts is located on the island of New
Providence which is the commercial centre and where
66% of the total population reside.
The remaining 100 Megawatts is spread over 26
power stations located on 15 island groups.
POWER GENERATION MACHINERY
All generation of electrical power is produced
either by
 Large slow speed diesel generators
 Combustion turbines in either simple cycle or
combined cycle mode.
 Medium speed or high speed diesel generators

GENERATION CAPACITY (NEW PROVIDENCE)



There are two power stations on the island of New
Providence which also provide power for the tourist
resort of Paradise Island.
Clifton Pier Power Station located at the south-west
coast of the island and adjacent to the bulk oil
terminal of Exxon, Chevron and SUN OIL (Shell
licensee)
Blue Hills Power Station located in the centre of the
island and connected to Clifton Pier by two six-inch
fuel pipelines which supply gas oil.
GENERATION CAPACITY (NEW PROVIDENCE)
CLIFTON PIER POWER STATION
 Clifton Pier Power Station (175 Mw’s) consists
of 9 slow speed diesel engines.
 4 of Sulzer design at 10.7 Mw’s each
 2 of Burmeister & Wain design at 26.5 Mw’s
each
 2 of Burmeister & Wain design at 31.5 Mw’s
each.
 1 of Burmeister & Wain design of 18 Mw’s.
GENERATION CAPACITY (NEW PROVIDENCE)
BLUE HILLS POWER STATION




Blue Hills Power Station (160 Mw’s) consists of 4
simple cycle combustion turbines and 1 combined
cycle unit consisting of 2 combustion turbines feeding
1 steam unit.
4 Hitachi turbines at 23.5 Mw’s each.
2 General Electric turbines @ 20 and 21Mw’s.
1 Kawasaki steam turbine at 22 Mw’s powered by 2 of
the Hitachi turbines.
GENERATION CAPACITY (FAMILY ISLANDS)








Exuma – 4 Power Stations
Great Harbour Cay – 1 Power Station
Long Cay – 1 Power Station
Long Island – 1 Power Station
Mayaguana – 1 Power Station
Rum Cay – 1 Power Station
San Salvador – 1 Power Station
Inagua – 1 Power Station
GENERATION CAPACITY (FAMILY ISLANDS)
Abaco – 4 Power Stations
 Acklins – 2 Power Stations
 Andros – 3 Power Stations
 Bimini – 1 Power Station
 Cat Island – 1 Power Station
 Crooked Island – 1 Power Station
 Eleuthera – 3 Power Stations

FUEL OIL CONSUMPTION (NEW PROVIDENCE.)

Currently, all fuel oil consumption is on the island of
New Providence being burnt in the slow speed diesels.

There are plans to also burn fuel oil in the new power
station that has been built on the island of Abaco.

It is anticipated that the use of fuel oil will also be
migrated to other islands as machinery is replaced.
FUEL OIL AND LOW SPEED TWO STROKE DIESELS
Combustion turbines operate between 18% to
28% thermal efficiencies over their load range.
 Combustion turbines in combined cycle mode
still only produce efficiencies over their load
range of between 32% to 40%
 Low speed two stroke diesels produce
efficiencies over their load range of between
48 – 53%.

RELATIVE COSTS
The low speed two stroke diesel with its high
efficiencies and ability to effectively and
reliably burn the low cost residual fuels
generates electricity on the order of 15 - 20
cents/kwh (fuel cost) over their entire load
range.
 Combustion turbines which do not have the
efficiency of the diesels and which burn the
more expensive gas oils produce power in the
area of 30 - 40 cents/kwh (fuel cost).

Heavy Fuel Oil
burn or capable
Heavy Fuel Oil
retrofit possible
Heavy Fuel Oil
future consideration
GENERATION CAPACITY (FAMILY ISLANDS)
Abaco – 4 Power Stations (1 with HFO capability)
 Acklins – 2 Power Stations
 Andros – 3 Power Stations
 Bimini – 1 Power Station(HFO retro-fit possible)
 Cat Island – 1 Power Station (Future HFO considered)
 Crooked Island – 1 Power Station
 Eleuthera – 3 Power Stations(1 with HFO retro-fit

possibility)
FUEL OIL CONSUMPTION
(NEW PROVIDENCE.)
1,300
1,200
1,100
1,000
900
800
700
600
500
400
300
200
100
0
Kilo-Barrels
2004 2005 2006 2007 2008 2009
GAS OIL CONSUMPTION
(NEW PROVIDENCE.)

Gas oil consumption on New Providence is in
the combustion turbines as well as a limited
quantity for start-up and shut down of the slow
speed diesels.
GAS OIL CONSUMPTION
(NEW PROVIDENCE.)
1,300
1,200
1,100
1,000
900
800
700
600
500
400
300
200
100
0
Kilo-Barrels
200420052006200720082009
GAS OIL CONSUMPTION
(FAMILY ISLANDS)
600,000
500,000
400,000
300,000
Barrels
200,000
100,000
0
2004
2006
2008
FUEL OIL
QUALITY ISSUES

The major concerns over heavy fuel quality are:
Parameter
Density
Aluminum +
Silicon
CCAI
Concern
Must be less than 991 for ease
of centrifuge function.
Kept to a minimum to prevent
cylinder liner scuffing.
Preferably below 850 to avoid
ignitability problems
GAS OIL
QUALITY ISSUES

The only issue recently over gas oil quality was :
Parameter
Cetane
Concern
Ensure ignitability particularly
because we operate a mix of
medium and high speed diesel
engines from various
manufacturers
FUEL SOURCES

The Bahamas has no oil of its own and all fuel is
imported.

Traditionally, the bulk fuel supplier has been one of
the local three major oil companies, Shell, Esso or
Texaco/Chevron.

These local entities would establish joint ventures
with their larger trading partners to meet the supply
demand.
BULK STORAGE TANK FARM
No. 2 diesel
TK. 10 = 80 Kb
Tk. 11 = 110 Kb
TOTAL = 190 Kb
H.F.O.
Tk .13 = 95 Kb
Tk. 14 = 95 Kb
Tk. 15 = 95 Kb
TOTAL =285 Kb
BERTH REQUIREMENTS


This Sea Berth is designed to accommodate Tankers
of up to 45,000 DWT, with a maximum length of 630
ft., 225 ft. vessel parallel mid-body in normal ballast,
a freeboard of 9.0-ft. and a maximum draft of 35 ft. 9
inches
The term tug means a vessel designed for assisting
vessels with docking and undocking in restricted
waters and an available horsepower of 2500 hp or
greater. These tug requirements are considered the
minimum acceptable by the berth operator.
CLIFTON PIER
DEEP WATER BERTHING FACILITY
LOGISTICS
NEW PROVIDENCE



Being an archipelago spread over an area roughly the
size of Florida, all fuel supply is waterbourne.
Bulk supply for both New Providence and Family Island
consumption is by ocean going tanker to the deep
water port at Clifton Pier where the Clifton Pier Power
Station is located.
Gas oil is delivered to the Blue Hills Power Station on
New Providence via two 6” underground pipelines
LOGISTICS
FAMILY ISLANDS



Gas oil is delivered to 26 power stations on 15 islands
by intercoastal tanker.
This is the responsibility of the bulk fuel supplier who
enters into an agreement with a third party that
charters purpose built vessels.
The schedule of deliveries is managed by BEC
providing weekly updates of the inventories and burn
rates at each location.
LOGISTICS (FAMILY ISLANDS)
DIFFICULTIES


The intercoastal tankers take on fuel at the Clifton
Pier loading facility. Each of three ships has a capacity
of between 160,000 to 210,000 gallons. (3,800 –
5,000 barrels)
Some locations however cannot accommodate the
vessel fully laden. The vessel would then first off-load
some of its product at a port with deeper draft before
proceeding on to the shallower draft facilities.
INTER-COASTAL TANKER
FAMILY ISLAND DELIVERIES.
LOGISTICS (FAMILY ISLANDS)
DIFFICULTIES

Further difficulties exist since there is a wide
variation in consumption patterns for many of
the locations depending on the time of year
and whether any local festivals are occurring.
These generally take the form of regattas, deep
sea fishing tournaments, homecomings, or
crab festivals.
LOGISTICS (FAMILY ISLANDS)
DIFFICULTIES

Weather plays an important part in the delivery to Family
Islands. During hurricane season a couple of years ago,
deliveries were delayed at several locations up to 11 days due
in part to Hurricanes Gustav, Hanna, and Ike

There are also the concerns of safety which prohibit pumping
outside daylight hours.

Communication issues between each location and the ship.

Inventory coordination at each location
BULK DELIVERIES

Heavy Fuel Oil is delivered in quantities of
130,000 to 160,000 barrels.

Gas Oil is delivered in quantities of 90,000 to
120,000 barrels.
ANTICIPATED CHANGES

BEC is currently considering the design and construction of
two additional large slow speed diesels at Clifton Pier.

These machines, anticipated to be rated at 40 Megawatts
each will displace much of the current gas oil consumption
with heavy fuel oil and cater more efficiently to the demand
for power.
ANTICIPATED CHANGES
FAMILY ISLANDS
The new power station on the island of
Abaco was designed and built to burn HFO.
Several slides follow showing its
construction.
 Financial constraints will require other
Family Island stations to operate on HFO as
machinery is upgraded.

GRAND BAHAMA POWER COMPANY
The island of Grand Bahama is the second most populous
island in the Commonwealth of The Bahamas. It contains the
city of Freeport a planned residential, commercial and industrial
centre. The Grand Bahama Power Company is an independent
facility not owned by the Government of The Bahamas or the
Bahamas Electricity Corporation. Its ownership rests with the
Grand Bahama Port Authority and Emera Inc which operates
several electricity facilities in Canada and the Caribbean.
GENERATION PLANT
•7 UNITS WITH A COMBINED CAPACITY OF 137.5 Mw
HEAVY FUEL OIL BURNING UNITS
•TWO MITSUIBISHI SLOW-SPEED DIESELS AT 13.5 Mw EACH
•ONE MAN MEDIUM SPEED DIESEL AT 18.5 Mw
•A B&W / General Electric Boiler turbine rated at 17Mw
•A Mitsubishi boiler turbine rated at 40 Mw
GAS OIL BURNING UNITS
•GENERAL ELECTRICI COMBUSTION TURBINE RATED AT 15Mw
•A JOHN BROWN COMBUSTION TURBINE RATED AT 20 Mw
• FUEL OIL USED BY GRAND BAHAMA POWER COMPANY IS
PURCHASED FROM WESTPORT PETROLEUM WHICH MAINTAINS
LEASED TANKAGE AT THE LOCAL (BORCO) FACILITY
•GAS OIL IS SUPPLIED BY THE LOCAL COMPANY FOCOL
Fuel usage for 2008
HFO
681,840 barrels
Diesel 103,400 barrels
Fuel usage for 2009
HFO
Diesel Fuel
649,110 barrels
144,070 barrels
No growth occured during 2010.
GRAND BAHAMA POWER COMPANY
HEAVY FUEL OIL
FLASHPOINT (Min) F
178
D-93
API (min)
11.0
D – 1298
POUR POINT (max)F
60
D - 97
VISCOSITY (Min) SSF @122F
45
D – 445, 2161
VISCOSITY (Min) SSF @122F
200
D – 445, 2161
HEAT VALUE (btu/bbl)Min
6,300,000
D - 240
Sulphur %wt (Max)
3.0
D – 4294
WATER % max
0.5
D-95, D-473
VANADIUM (ppm) Max
300
D-2788
HEAVY FUEL OIL (cont’d)
SODIUM (ppm)Max
100
D-2788
ASH (%wt) Max
0.15
D-482
CATFINES(ppm max) Al+Si)
60
ISO-10478
MicroCarbon Residue (%wt) Max
18
ISO-10307
Total Sediment Potential (%wt)Max
0.10
ISO-10370-2
GAS OIL
API (Min)
33
D-1298
VISCOSITY @122F (min)
1.8
D-445
VISCOSITY @122F (max)
5.8
D-445
SULPHUR (%wt) max
0.5
D-4294
POUR POINT (F) max
40
D-97
WATER & SEDIMENT (%volume) max
0.1
D-95, 473
FLASH POINT (F) min
140
D-93
VANADIUM (ppm) max
2
D-2788
SODIUM (ppm) max
5
D-2788
ASH (%wt) max
0.005
D-182
CALORIFIC VALUE (btu/gal) min
138,000
D-240
Generation Facility Summary
Profile
Configuration
Heat Rate and Capacity Factor
Steam/Diesel/
Combustion Turbine
Capacity factor
11,889
11,703
Number of units
7
11,810
Heat rate (Btu/kWh)
36%
36%
35%
34%
11,332
33%
11,170
Manufacturer
31%
Mitsubishi/BWSC/
GE/John Brown
Fuel type
Oil
Installed capacity (Mw) (2008)
137.5
Net production (Gwh) (2008)
409
2003
2004
2005
2006
2007
2008
137.5
137.5
2007
2008
Installed Capacity (MW)
155.5
 The generation assets of the Company are all situated on a 47 acre
plot of land in the Freeport Industrial Park
 Currently, about 50% of the site is used and the other 50% is still
available for expansion purposes
10,995
140.0
140.0
2003
2004
155.5
 The system’s peak demand in 2008 was 74 MW
2005
2006
62
ADDITIONAL GENERATION

Given the benefits of diesels burning fuel oil,
the Grand Bahama Power Company is currently
adding 51 Mw of fuel oil burning diesels.

It is anticipated that financial considerations
will force this trend to continue throughout the
entire Caribbean during the upcoming years.
Thank you.
Should there be any questions, I can be
contacted at:
 ecl@batelnet.bs
 Alternate email: cndbethel@coralwave.com

C.N. DeCosta Bethel
Operations
Engineers & Consultants Ltd
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