part 1: overview of cogeneration and its status in asia - Fire

Summary of country study – Viet Nam
There is one big nitrogen fertilizer plant in Viet Nam, located in Habac province. The plant was
put into operation 30 years ago. The cogeneration plant consists of five coal-fired boilers: two
large boilers with capacity to produce 75 tons/hour each, and three smaller ones, each with a
capacity to produce 35 tons/hour. Steam produced at 40 bar and 450°C is partly supplied
directly to the processes, and partly through a 6 MW backpressure turbine. In addition, there
are two condensing turbines to meet the plant’s electricity demand, each with a capacity to
produce 6 MW of electricity. Like in the case of most other plants, the performance of the
cogeneration plant has degraded after long periods of operation and lack of proper
maintenance. Presently, the boilers have efficiencies ranging from 70 to 75 per cent whereas
the turbine efficiency varies from 24 to 26 per cent only. Though there is plan to rehabilitate
and upgrade the existing facilities, implementation is delayed mainly due to financial
constraints.
The first unique cogeneration system in commercial sector in Viet Nam was brought into
operation on 18th August 1998 in CORA super-market, a member of Bourbon group, in Dong
Nai province. It consists of two diesel generators, each capable of producing 1200 kW. In
addition, there are two absorption chillers, each of 600 kW cooling capacity, and two electric
chillers, each of 400 kW cooling capacity. The main reason for setting up this cogeneration
system is the necessity for reliable power supply. The company is keen to synchronize its
cogeneration plant to the national power grid for system stabilization.
4.2.3 Identification of suitable sites for pre-feasibility study
The main criteria followed for the selection of sites for pre-feasibility study are the following:
• important consumers of electricity and heat;
• acceptable heat-to-power ratios;
• willingness of the management to apply cogeneration technology;
• user has plans for renovation or expansion of the existing facilities;
• management is aware of the benefits of energy conservation and efficiency.
Up to now, no study has been done on the sectoral power demand in Viet Nam as well as
their load shapes as a function of time. In this report, the identification of potential study sites
is based on the list of consumers (provided by the power utility) which have a demand
exceeding 1000 kW, combined with the list of boiler owners (provided by the Regional
Departments of Industrial Safety, Ministry of Industry).
Rough estimation of the steam and electricity demand patterns had to be done in most cases
as majority of factories lack instrumentation and do not have regular energy monitoring and
recording facilities.
After the identification and direct contact, eight sites including factories and commercial
buildings were chosen for the pre-feasibility study.
During on-site visits of those establishments, questionnaires were filled out and direct
discussions were held with the factory management.
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