It was formed out of the Electrical Department which had its beginnings 104 years ago in Development was very mild UNTIL CASTRO CAME TO POWER AND CUBA WENT COMMUNIST American tourist trade shifted to The Bahamas
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
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.
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%.
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.
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.
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.
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.
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.
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.
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
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.
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.
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 20 and 21Mw’s. 1 Kawasaki steam turbine at 22 Mw’s powered by 2 of the Hitachi turbines.
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
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
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.
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%.
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 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 cents/kwh (fuel cost).
Heavy Fuel Oil burn or capable Heavy Fuel Oil retrofit possible Heavy Fuel Oil future consideration
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)
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.
The major concerns over heavy fuel quality are:ParameterConcernDensity Must be less than 991 for ease of centrifuge function. Aluminum + Silicon Kept to a minimum to prevent cylinder liner scuffing. CCAI Preferably below 850 to avoid ignitability problems
The only issue recently over gas oil quality was :ParameterConcernCetane Ensure ignitability particularly because we operate a mix of medium and high speed diesel engines from various manufacturers
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.
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.
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
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.
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.
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.
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
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.
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.
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.
The following 7 slides show various stages of the construction of the power station at Wilson City on the island of Abaco.
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 Mw 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 HEAVY FUEL OIL BURNING UNITS 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 649,110 barrels Diesel Fuel 144,070 barrels No growth occured during 2010.
HEAVY FUEL OIL FLASHPOINT (Min) F178D-93 API (min)11.0D – 1298 POUR POINT (max)F60D - 97 VISCOSITY (Min) – 445, 2161 VISCOSITY (Min) – 445, 2161 HEAT VALUE (btu/bbl)Min6,300,000D Sulphur %wt (Max)3.0D – 4294 WATER % max0.5D-95, D-473 VANADIUM (ppm) Max300D-2788 GRAND BAHAMA POWER COMPANY
GAS OIL API (Min)33D-1298 (min)1.8D-445 (max)5.8D-445 SULPHUR (%wt) max0.5D-4294 POUR POINT (F) max40D-97 WATER & SEDIMENT (%volume) max0.1D-95, 473 FLASH POINT (F) min140D-93 VANADIUM (ppm) max2D-2788 SODIUM (ppm) max5D-2788 ASH (%wt) max0.005D-182 CALORIFIC VALUE (btu/gal) min138,000D-240
62 Heat Rate and Capacity Factor Profile Generation Facility Summary 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 The system’s peak demand in 2008 was 74 MW Installed Capacity (MW)
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: Alternate C.N. DeCosta Bethel Operations Engineers & Consultants Ltd