Prospect of gas industry and the role of liquefied natural gas ( LNG ) in Vietnam during 2011 – 2035

The paper presents the detailed data of gas demand for power, fertilizer and other industries in Vietnam during 2011–2015, as well as forecasted data for 2016–2025 and 2026– 2035 phases. The results demonstrate that the domestic gas industry cannot meet the market requirement, the inadequacy is estimated of 30%. Liquefied natural gas (LNG) receiving terminal installation for import is considered as a feasible solution to the problem. However, the major barrier is that the gas pipeline system is discrete in the whole country, the configuration of LNG receiving terminal must be therefore selected and designed reasonably. By analysis, Vietnamese LNG market is a high potential in 2016–2035 phase.


INTRODUCTION
The electric energy in Vietnam was previously from hydroelectric and coal.These affect to environment remarkably because of carbon dioxide emission.The energy demand in Vietnam has been increasing dramatically due to industrial development.Under the pressure of accelerating energy demand and environmental preservation, the electric power by hydroelectric and coal is gradually replaced by natural gas turbine in Vietnam since 1995.The gas industry plays therefore a very important role in the Vietnamese economy as well as the national energy security.The data is detailed in Figure 1.

THE VIETNAMESE GAS
In order to reach 90.8% of total demand, the gas industry received the 4.65 billion USD of investment by government.The practical natural gas gathering increased very slowly in the 2011-2015 phase, because the probe drilling and reserve estimation were not reliable.These caused some wells of low reserve were not able to be commercially exploited.The gas market is almost for power production, but petrochemical industry is just on research.The LNG market has not developed yet since there were not many LNG consumers.Another reason is that the gas pipeline system is discrete in the country as in Figure 2 [2], the gathered natural gas was not then able to balance between the regions.
The detail for regions is as follows:  For The North region, the wells of low

THE VIETNAMESE GAS INDUSTRY DURING THE 2016-2025 PHASE
The forecast of supply, demand and the supply-demand balance of natural gas for the different regions are shown detailed in Table 1.

THE VIETNAMESE GAS INDUSTRY DURING THE 2026-2035 PHASE
The data in Table 1 shows that the domestic natural gas resources cannot meet the market demand in the 2026-2035 phase.The supply-demand balance of natural gas is negative for The North, The Southeast and The Southwest regions, but positive for The Central region.The domestic gas would only reach 70% if all of planning projects are run and completed, the inadequacy of 30% is hence inevitable.
Nevertheless, the inadequacy can be increased because all of projects are difficult to complete in planning.The composition of consumers is hopefully 77% of power production, 18% of fertilizer production and 5% of others including compressed natural gas (CNG) for transportation.
The total natural gas supply during 2016-2035 is forecasted around 294.   For The Central region, the practical natural gas from Ca Voi Xanh well is over times higher than the forecast.Therefore, the natural gas for power plants ( in total) in The Central region is contented.
Moreover, the natural gas supply will be supplemented by Bao Vang well.As consequently, the petrochemical industry should be considered for development in this region. For The Southwest region, the contribution of Kien Giang power plant increased the natural gas demand in the region.
The decreasing of PM3CAA resource since 2025 that affects to the natural gas supply.In order to maintain the fuel gas for power plants, the estimation of gas reserves is implemented at new resources of U Minh, Nam Du, Hoa Mai, Khanh My and Dam Doi.

SOLUTIONS SUGGESTION
In recent situation, LNG import is considered as feasible solution to complement the inadequacy of natural gas in the country.The other reason for this choice is the environment problem [3,4].The natural gas is the most environmental friendly fossil fuels because the mainly composition is methane.
Accompany to the LNG import, the LNG receiving terminals and regasification process projects have to be run and completed since 2019 in The Southeast region, in The Southwest region since 2022 and in The North region since 2025.
The circumstance in The Central region is better, therefore, there will be two options: installation of small scale LNG production plant for petrochemical industry or connection the gas pipeline system from this region to others.

THE ROLE OF LNG IMPORTATION IN VIETNAMESE GAS INDUSTRY
The national energy security and sustainable development play the important role in Vietnamese society.As forecasted, LNG has to be imported since 2019 to complement the insufficient natural gas supply.The inadequacy higher to 30% of demand in the 2026-2035 phase.The requirement of LNG import is forecasted as in Figure 4   The LNG is pumped to the storage tank from floating production storage and offloading (FPSO) directly.There is always amount of LNG vaporized under storage process which is called boil of gas (BOG).The BOG is normally compressed to liquid and turned back to the storage tank.The LNG is re-gasified before transported to the end consumer by gas pipeline system.The capital cost is almost contributed by the storage tank, compression and regasification processes.Therefore, the LNG storage tank should be designed at an appropriate BOG rate of 0.05% in mass fraction.This lowers the compression duty, as well as the capital and operation cost of compression process.For regasification process, the open rack vaporizer should be selected because Vietnam is in seaside and tropical region, sea water is as an infinite heat source for LNG vaporization.

CONCLUSIONS
The energy demand is growing rapidly in Vietnam, while domestic natural gas resource is decreasing.Therefore, the LNG importation will be growing up to compensate the degradation.The total LNG requirement is forecasted of 13.75The Central region, the natural gas supply is higher than demand, the small scale LNG production plant should be hence considered.As a result, the Vietnamese LNG market will grow potentially.Furthermore, the application of optimizing technology to Vietnamese LNG production is indispensable and has to be researched as soon as possible.

Figure 1 .
Figure 1.The comparison of forecasted and practical natural gas capacity during 2011-2015 phase [1]

Figure 2 .
Figure 2. Map of Vietnamese natural gas resource and currently gas pipeline system [2] 9 billion m 3 with maximum capacity of 20 billion m 3 per year in 2024-2025 because of starting up of new resources such as Su Tu Trang, Sao Vang, Ca Voi Xanh and Block B.


For The Southeast region, the decreasing of reserve at Thien Ung well and the uncompleted Nam Con Son 2 pipeline made the total gathered natural gas decreasing.On the other hand, the Nam Con Son 2 pipeline has not focused on the large reserve of wells such as Su Tu Trang, Sao Vang, Ca Rong Do, Ca Kiem Xanh, Ca Kiem Nau, Cobia… the reason is that the estimation of gas reserves was not exactly and reliably.These made the power plants are not yet installed as planned, for example Son My , Nhon Trach 3 and Nhon Trach 4.
[1].The LNG has to be imported in The Southeast region earliest in 2019, and accelerates the capacity from 2024.The Thi Vai LNG Import Harbor Depot project with a capacity of 1 million tons per year is being started and expected to come into operation by 2017, while the 3 million tons per year of Son My LNG Import Harbor Depot is predicted to start up during 2019-2020.Almost of LNG import is supplied to the new power plants such as Son My, Nhon Trach 3 & 4 and Hiep Phuoc enlargement [1].The natural gas supply for The Southwest region starts insufficient since 2022, and a new LNG receiving terminal with a capacity of 3 million tons per year is planned to set up at Hon Khoai for supply to power plants in Kien Giang and O Mon [1].For The North region, the LNG resource which will be imported through the Cat Hai LNG receiving terminal with 1 million tons per year of capacity, supply to the Hai Phong 3 power plant (4 x 600MW) hopefully operating between 2025-2027 [1].

Figure 4 .
Figure 4.The LNG import capacity during 2019-2035 in million tons [1] Nevertheless, the above solutions are just the first selection for the first phase of the project due to low capital cost.The open rack vaporizers lose a lots of energy saving opportunities.The lost energy in the compression and regasification processes can be saved for power generation, air separation and cold storage [6-9] … The modern technology and energy saving solutions will be hence applied in the second phase of the project.There will be many opportunities for research, investment and development in Vietnamese LNG market.