Meghnaghat, Bangladesh

A $300 million, 450MW Combined Cycle gas-fired power station is now operating in Meghnaghat, Bangladesh. The plant was built by AES (Allied Energy Systems) Corp, the US-based producer. It has since been sold to British company CDC Globeleq, which also takes over a 22-year Power Purchase Agreement (PPA) with Bangladesh Power Development Board (BPDB).

At the time, the 22-year agreement secured the world’s lowest tariff for BPDB, with the Development Board taking the electricity generated up to 85% plant load factor. PDB is currently considering a second construction phase (Meghnaghat Phase-II).

ADDITIONAL BASE-LOAD CAPACITY

Meghnaghat will supply domestic, agricultural and industrial users. The project brings extra base-load capacity to help solve Bangladesh’s present and forecast power shortages. The country may face acute power crisis by 2004, when the country’s demand is expected to rise to 4,200MW, because of lack of investment in the power sector. The PDB also aims to establish plants to meet the estimated requirement of above 6,000MW power in 2007.

HYDRAULIC MODEL STUDY

The project lies downstream of the Meghna Bridge at Meghna Ferryghat, an area that is influenced by significant tidal action during the dry season. The plant draws cool water from the river and discharges the hot water into the river.

A Hydraulic Model Study for the plant by DHI (Danish Hydraulic Institute)/ SWMC (Surface Water Modelling Centre) included thermal plume and morphological modelling.

The Hydraulic Model Study avoided inappropriate location of intake and outlet of water, which would endanger aquatic life and cause tremendous loss of efficiency. It examined river hydraulics, advection-dispersion of heated water and sediment transport and scouring along the proposed location of the plant using advanced mathematical tools.

CONSTRUCTION

Meghnaghat was constructed by Hyundai Engineering and Construction, using Combined-Cycle Gas Turbines fed by natural gas.

The plant uses two V94.2 gas turbines with air-cooled generator from Ansaldo Energia s.p.a. The V94.2 is a single shaft, cold-end drive dual combustor with 16 burners and a heavy-duty gas turbine. It includes a 16-stage axial compressor and a 4-stage axial turbine with a common rotor.

The generator is of a conventional design for use with gas turbines. The air-cooled, two-pole machine has a cylindrical rotor and is ventilated in closed circuit configuration using air-to-water heat exchangers located in the lower part of the stator frame. Dry low-NOx combustors achieve the guaranteed NOx emission level. Steam or water injection is not required.

HEAT RECOVERY STEAM GENERATORS

Two HHI(Hyundai Heavy Industries) triple-pressure, natural-circulation Heat Recovery Steam Generators use supplementary firing. The HRSGs are of natural circulation horizontal type design.

The HRSGs produce superheated HP steam, superheated reheat steam and superheated LP steam. They are designed for 100% full-load continuous operating conditions. The HRSGs use supplementary firing to achieve the required 450MW net output at the high voltage side of the outgoing terminals of the 230kV transformer. The HRSGs, pumps and auxiliaries are designed for outdoor installation.

The plant uses a FUJI triple-pressure (HP, IP and LP), reheat, condensing, down exhaust type steam turbine with air-cooled generator. The steam turbine has no steam extraction. The two-pole generator is totally enclosed and water-to-air-cooled.

The steam turbine is installed indoors for environmental protection and acoustic attenuation. The steam turbine building has an overhead travelling crane for heavy-load maintenance lifting. The building has suitable indoor laydown areas for plant maintenance.

FINANCING

The Meghnaghat project involved about $250 million of debt facilities provided by the Asian Development Bank and other lenders. An $80 million loan – the largest from any Bangladeshi financial institution – was extended by IDCOL (Infrastructure Development Company Limited).

Early 2003, CDC Globeleq paid around $437 million, including equity and assumed debt, for the 450MW Meghnaghat and 360MW Haripur plants in Bangladesh. Formerly the British Commonwealth Development Corporation, CDC Globeleq is the emerging markets power company of CDC Group plc. As part of the deal, CDC Globeleq will take over AES’s commitment to provide more than $1 million funding for the construction of a new hospital, a school and a bridge.