Noah F GwariroManaging Director

Zimbabwe Power

CompanyZIMBABWE

REFURBISHMENT OF HWANGE POWER STATION

INTRODUCTION

� Zimbabwe Power Company (ZPC)is part of the ZESA Holdings; the power utility for Zimbabwe

� ZPC has the mandate to construct, own, operate and maintain power generation stations for the purpose of generation and electricity supply.

INTRODUCTION Continued

� ZPC operates four thermal power stations and one hydro power station with a combine installed capacity of 1960

�Hwange (920MW) base load

� Kariba (750MW)load following (system regulation)

� Small thermals (290MW) strategic reserve for dispatch during winter peak and major outages at Hwange and Kariba

ABOUT HWANGE POWER STATION

� Built in two stages

� Stage I – 4 x 120MW commissioned between 1983 and 1986

� Stage II – 2 x 220MW commissioned between 1986 and 1987

� Base load coal-fired plant utilising diesel and coke oven gas as secondary fuels.

MAJOR OVERHAULS

� Done every 5 to 6 years or 50 000 running hours

� Funding mainly from the World Bank

�Without WB funding units falling due for major overhauls in 2001 could not be funded

� Restricted M/O based on turbine main done on units 5 & 6 in 2003 and 2004 respectively.

MAJOR OVERHAULS

� Deferred maintenance took its toll on plant availability, reliability and safety from 2005

� By 2006 two stage I units had exceeded the recommended running hours between major overhauls by more than 40%.

� Units that were overdue for maintenance were removed from insurance cover and had to be taken out of service. The station would run one or two units.

CHALLENGES

Funding

� Raising US$10millon for each of the four stage I units (US$40million)for foreign orders and services.

� Actual requirement not guaranteed as the condition of equipment could only be ascertained after opening up units

�Original Equipment Manufacturers (OEMs) wanted cash up-front for all orders including services.

CHALLENGES -Continued

Funding

� Raising an equivalent of US$4million for local purchases and services.

� Low revenues due to lack of cost reflective electricity tariff

�Hyper-inflationary environment

CHALLENGES -Continued

Manpower

� Skills flight at Hwange resulted in whole shifts being de-manned

� The major overhaul works had to be done by the reduced workforce that was also responsible for the running plant

� Absenteeism was a big problem such that planned works could not be done

CHALLENGES -Continued

Spares & Services Procurement

� Long lead times of up to 18months

� Dependency on OEMs and foreign suppliers as traditional local suppliers relocated from Zimbabwe

� Shortage of spares (consumables) from local market

FINANCING PLAN

� Through Southern African Power Pool (SAPP) meetings in 2006 ZESA and NamPower struck a deal for refurbishing the four stage I units at Hwange

� The deal was supported by the governments of the two utilities

� Formal agreements were concluded in 2007

FINANCING PLAN Continued

� ZESA, through its subsidiary, ZPC would execute the project with NamPower

� NamPower would provide a loan to ZPC through ZESA Holdings amount of up to US$ 40 million.

� ZPC repaying the loan with interest , over five (5) years through a Power Purchase Agreement (PPA).

� A project team of NamPower and ZPC staff was set up to implement the project.

FINANCING PLAN

� The loan repayment entails the export of 150MW power on a firm basis.

� Proceeds of power exports to be utilised for loan repayment and building up of a fund for future major overhauls

� The power exports would be staggered from 40MW on completion of the first unit to 150MW by the end of the project

SCOPE OF WORK

�Overhaul of turbines and auxiliaries

�Overhaul and refurbishment of Stage I Boiler Feed Pumps (BFPs) to restore standby plant and restore operational efficiency of running pumps.

SCOPE OF WORK Continued

�Modification of the boiler nose area for Units 1, 3, and 4 to reduce outages due to boiler nose tube failures

� Upgrading of the process Operating System

SCOPE OF WORK

Continued�Overhaul and refurbishment of 16 mills for the four Stage I units to restore economic and efficient operational status

� Upgrading of 3.3kV switchgear

IMPLEMENTATION OF MAJOR OVERHAULS

WORKS COVERED

� Boiler nose tubes were modified on three units

� Some boiler tubes were replaced after having been identified through non-destructive testing

�Mills were overhauled

� The operating system was upgraded

IMPLEMENTATION OF MAJOR OVERHAULS

WORKS COVERED

� Switchgear was upgraded

� Turbo-alternator sets were overhauled

� New boiler feed pumps (BFPs)were procured and the installation is in progress

� Condenser re-tubing was carried out

IMPLEMENTATION OF MAJOR OVERHAULS -CHALLENGES

IMPLEMENTATION OF MAJOR OVERHAULS -CHALLENGES

Condition of Equipment

� The condition of equipment had deteriorated resulting in increased work scope to rectify defects

� Balancing of all rotors, turbine HP, LP and generator rotor

� Some equipment with long lead times had to be reconditioned as an interim measure to allow completion units, e.g. BFPs, actuators

IMPLEMENTATION OF MAJOR OVERHAULS -CHALLENGES

� Securing the a slot in the service providers’programmes was difficult and affected project implementation

� Unit 1 had multiple barring gear failures

PROJECT COMPLETION

� To date three units have been completed and commissioned

� The progress of the project improved in 2009as the Zimbabwean economy was stabilised by the adoption of a multi-currency regime

� Some new equipment like BFPs will be retro-fitted to the units whilst the units are in service

IMPLEMENTATION OF AGREEMENT

DATE EVENT

Feb 2007 ZESA and NamPower sign Loan and Power Purchase Agreements

Mar 2007 Loan disbursement

Jan 2008 Export of 40MW to NamPower

June 2008 Export of 80MW to NamPower

Oct 2008 Export of 120MW to NamPower

Oct 2008 Export of 150MW to NamPower

POWER PURCHASE AGREEMENT� ZESA commenced

exporting power to NamPower in fulfillment of this agreement in January 2008

� The power exports have been beneficial to both ZPC and NamPower as the critical needs of both parties have been met through the Agreement

THANK YOU