After 30 years of the re-establishment of the province, Thua Thien Hue Power Company (TTHPC) has developed and changed radically. This stems from the contribution of all relevant authorities and the effort of the Party and provincial people, in which there is the endeavor of power sector in general and of TTHPC in particular. The achievements which TTHPC attained, made an important contribution to the journey of 30 years full with glory but also imbued with sweat and tears.
Mr. Vu Thang _ provincial party secretary participating in energization ceremony of 110kV E6 – Ngu Binh in 12/1990
On 30/6/1989, the province Binh Tri Thien (BTT) was re-split into 03 provinces: Quang Binh, Quang Tri, Thua Thien Hue. Till 10/1989, to match the administrative boundary, Thua Thien Hue Power Department under Power Company 3 was established under the decision number 646/QD/NL/TC-CB-LD dated 07/10/1989 of Energy Ministry, on the basis that BTT Management Department and Power Distribution Department had been split into 03 separate Provincial Power Department.
After the provincial split, staff and workers of Thua Thien Hue Power Department both continued to reinforce the old power source and completed the work for transport, construction and installation of Ngu Binh Power Plant in 1989 within only 18 months, including 05 Г72 generator sets and 02 SKODA generator sets with total capacity of 7.9 MVA and with relatively modern equipment for generating additional power to increase generated power and voltage for loads. Apart from the additional power source, power grid was reinforced and rehabilitated as well for medium voltage (MV) grid from 3.3kV to 6kV, for low voltage (LV) grid from 0.2kV to 0.4kV. Till the end of 1989, the provincial split was completed. Thu Thien Hue province possessed 26 generator sets with total capacity of 9.25MVA while the peak demand of the province at that time was 17MW; therefore, alternate outage schedule was applied (one night off then one night on). Power sales only reached 56.2 mil. kWh; the volume of materials and equipment were managed: 855.16 km of MV power lines, 272 distribution substations with total capacity of 51MVA, 02 intermediate substation with total capacity of 5.8MVA, 20,870 customers, 48/102 of communes, wards and towns connected to power grid, 46.2% of provincial households connected to power grid.
The power department strived for maintaining, reinforcing and developing power system. From 10/1989 to 12/1990, the electricity Hue city was supplied from 07 generator sets of Ngu Binh Power Plant with total capacity of 7.9MVA and 17 generators with product code Г66-540kW, Г65-400kW manufactured in Rusia, 01 generator with product code SULZER from the former French imperial government at the generation workshop of Hue with total installed capacity of 9.6MVA and 02 6kV feeders from E8 substation via 04 machines with product code MAL and Г72 of Hue Textiles Company. After the period of construction, on 21/12/1990, Hue 1 (E6) 110/35/6kV-25MVA substation at Ngu Binh and 35kV feeders were conducted acceptance procedures and energized.
Since 4/1991, load of Hue city has been supplied with electricity from national power system, not only from 35kV power line to Hue 35/6kV-2x6,300kVA intermediate substation, the Hue intermediate substation also received the residual power of 110kV E8 substation via two 6kV E8 feeders (the Det-An Cuu double-circuit power line) in order to connect to Ngu Binh busbar and the Hue intermediate substation. Ngu Binh Power Plant was for generating additional power, voltage during peak hours at night. During this period, the historical role in generating electricity with diesel generators for local load demand had ended, power sector moved to the period of receiving national power via 110kV power line from Dong Hoi to Hue, yet the power quality of this period was not stable, blackout events occurred usually (there was a day when there are 20-30 times of blackout) because the power transmission line was long and the load demand was large and the voltage of 6kV busbar sometimes dropped to 3.8-4kV during nocturnal peak hours. During this period, apart from mobilizing all of Ngu Binh diesel generators for the additional power and voltage increase, the power department took advantage of the support from Central Load Dispatch Center (A3) to rise the voltage at 110kV E6, E8 substations for ensuring stable power supply to Thu Thien Hue province’s load demand. On 4/1992, 500kV power transmission line, a nationally monumental work, was put into construction; on 5/1994, the 1st phase of the work was energized; and on 09/1994, 500kV Danang substation was completed, provinces of central region as a whole as well as Thua Thien Hue province were received stable power quality from national power system via 500kV Danang substation, which terminated the historical role in mobilizing local generators and ushered in the new period of power supply from national power system. In 1994, 110kV power line and 110kV 35/6-25MVA Van Xa substation were energized for supplying power to Luksvaxi Cement Plant. On 08/3/1996, due to the change of Governing Ministry, Thua Thien Hue Power Department was changed into Thua Thien Hue Power Branch, a subsidiary of Power Company No.3 under the decision numbered 256/QD/DVN/TCCB-LD of Vietnam Power Corporation.
During this period, power source and power grid continued to be reinforced. In 10/1996, 35kV Binh Dien – A Luoi power line and 35/15kV-1,800kVA Bot Do intermediate substation were recovered and energized, which marked power supply from national power system to the last district of Thua Thien Hue. In 1997, power sector invested in 35kV power line and 35/6kV-3,200kVA Phu Thuong intermediate substation, 35/6kV-2x1,600kVA Huong Vinh intermediate substation, recovered and energized 35/10kV-1,800kVA Binh Dien intermediate substation. In 1998, the power branch rehabilitated and upgraded all power grid of Hue city into 22kV voltage level with the scope of work: 125.8km of 22kV semi-sheath overhead power line; 53.33km of 22kV underground cable; 187.7km of low voltage power line and 257 substations with total capacity of 75MVA. These projects were safely put into operation, helped to increase power capacity, quality in power supply for Hue city with total investment cost of 217.17 bil. VND by ODA capitals from French Government, the World Bank (WB) and domestic counterpart fund. Therefore, supplying power to the city was significantly improved, which contributed to creating a municipal beauty deserving of the image of the city, where there are many works recognized as world cultural heritages. Load growth rate of the whole province was reaching 14-17%/year during this period. In 09/1999, 110/22kV-25MVA Hue 2 (E7) substation was energized and connected to 110kV power line from E4 (Quang Tri province) to E6 (Hue 1), which ensured power supply to Ta Ngan 1,3,4,5 routes of Hue city. However, the historic flood occurring in early November 1999 caused severe damages toward lives and properties of local people. Thua Thien Hue power branch also bore the same heavy toll, the total estimating damage was over 30 bil. VND. The colossal flood also formed the new Hoa Suan estuary and caused serious damage to 01km of 22kV power line and 01km of 6kV power line, which triggered off power outage of 11 coastal communes. In the extreme weather, the companionship between the staff of the Power branch and the soldiers of the Navy force 2 was getting stronger when they cooperated in constructing nearly 1km of 22kV power line to connect two ends of Hoa Duan damp which had been split in the aftermath of the historic flood in 1999. The work was valued at 2.2 bil. VND and helped the people living in 11 coastal communes under 02 districts (Phu Vang and Phu Loc) to connect to power system for manufacturing, for stabilizing daily activities and for welcoming the upcoming millennium. By the end of 1999, Thua Thien Hue Power branch had managed 05 110kV substations with total installed capacity of 141MVA and 07 generator sets with the maximal generated capacity of 6.3MW, which met the maximal load demand of the province: 56MW. The power sale reached 201.7 mil. kWh, increasing by 3.6 times as opposed to that of 1989. The volume of managed MV/LV power line reached 2,169 km, increasing by 2.54 times. There were 874 substations, increasing by 3.21 time with total capacity 206 MVA, increasing 4.01 times. The total customers reached 36,700 customers, increasing 15.07 times. There were 145/152 communes (95.39%) and 75.29% households connected to power system.
From 2000 to 2009, the power branch received and developed rural grids via the Rural Electricity I (RE.I) project under WB’s loan, counterpart fund from Power Company 3. The power branch continued to invest in power grids for rural and remote areas at 13 communes of A Luoi, Nam Dong, Phu Loc, Phong Dien districts with 58 substations (total capacity of 1,826kVA) and 77.4km of 22kV power line and 90km of LV power line with total investment cost of 17.43 bil. VND. The work for receiving and returning the capital of rural MV power grid, which had been invested before 28/02/1999, was completed 01 month earlier as per regulation (i.e. 05/2002). The total volume of rural MV power grid comprised of 157 works, with over 500km of MV power line, 468 substations with total capacity of 70,790kVA, the total remaining value was nearly 29 bil. VND. From 2001 – 2003, the work for elimination of selling power via public meters was completed with 150 subprojects and over 8,000 retail meters.
Connection of Hong Thuy commune – A Luoi district to power system on 28/01/2003, the last commune of Thua Thien Hue province
On 28/01/2003, with the efforts of the power sector and the local authorities, Hong Thuy commune – A Luoi district, the last commune of Thua Thien Hue province was connected to the national power system with the scope: 9.7km of 22kV power line, 6 substations (total capacity of 139.5kVA), 7.1km of 0.4kV power line and the total investment cost of 3.5 bil. VND. At that moment, there are totally 152/152 communes, wards, towns of the province connected to the power system. The number of rural households, which connected to the power grid, reached 92% and there was no commune where the electricity tariff exceeded the regulated ceiling tariff (i.e. 700VND/kWh), which contributed to furthering the cause of agricultural, rural industrialization and modernization of the province. In 2003, the power branch continued to implement the construction of power line and substation for supplying power to phase I of Chan May economic-service zone, a project for supplying power to the S3 (Sanavan) border gate and energized on 16/5/2003 to record achievements of 113 years of birth of the great President Ho Chi Minh. The power branch also cooperated with relevant agencies under power sector to do acceptance procedure, to energize and to put into operation of 110/220kV-25MVA substation for supplying power to two 22kV feeders of Phu Bai industrial zone on 25/4/2003, which contributed to improving power quality, to ensuring continuous, stable power supply at Phu Bai industrial zone. The power branch also cooperated with local authorities to basically accomplish the conversion of management model for rural power system on 30/6/2004 as per the assigned progress and was awarded certificates of merit by EVN and the provincial People’s Committee. On 21/8/2004, 110/35/22kV-25MVA Lang Co was energized and put into operation, which ensured the power supply for Lang Co tourism zone, Lang Co – Hai Van service and the southern area of Phu Loc district. In 2005, to stabilize power supply to the southern loads of Thua Thien Hue province, Power Transmission Company 2 increased the capacity of 220/110-40MVA Hue 1 (E6) substation and that of 110/35/6kV-2x25MVA Van Xa substation in order to supply power to Luksvaxi Cement Plant and the northern loads of the province.
Energization ceremony at Hoi Mit, Hoi Dua area of Lang Co town on 31/8/2005
In 2005, after the severe accident from train-overturn derailment and under the guidance from the Provincial Party, the power sector invested in supplying power for Hoi Mit, Hoi Dua area to energize the project on 02/9/2005 in time. In 12/2005, the Power Branch cooperated with Transmission Company No.2 in putting 110/35/22kV-25MVA Phong Dien substation into operation, which ensured the stable power supply for the northern part of the province and sufficiently supported the load demand of Hue city, the southern part of Quang Tri province. Also, in 2005, the Power Branch received rural MV power line and 05 communes adjacent to Hue city for supplying power to each household. From 2006-2007, the Power Branch received, without returning initial investment cost, 49 wards, communes, towns for supplying power to each household; the volume of receipt was 684.41 km of LV power line and 58,349 customers, increasing the number of received communes to 116/152 (76.32%). At the end of 2009, in the province, there were 09 110kV substations with total capacity of 381MVA, which met the contemporary load demand of the province (148.3MWA); the power sales reached 201.7 mil.KWh, increasing by 3.6 time as compared to the year 1989; the Power Branch managed: (i) 3,281km of MV/LV power line (increasing by 3.84 time), (ii) 1,685 distribution transformers (increasing by 6.2 times) with total capacity of 432MVA (increasing by 8.48 times), (iii) 17 35/22kV substation with total capacity of 73.96MVA (increasing by 12.75 times), (iv) 179,000 customers (increasing by 8.58 times), 152/152 communes, wards, towns accessed to electricity (100%) in which 99.32% household was connected to power system.
Regarding investment, development of power system meeting the scientific and technological revolution, on 31/7/2012, 110/22kV – 40MVA Chan May substation and 0.622km of branches were energized with total investment cost of 143 bil.VND. Along with the acceptance, energization of 110kV Chan May substation, the Power Company also performed acceptance and no-load energization of 22kV power line under the project: “Supply power to Laguna – Lang Co eco-tourism area” whose scope of work includes 7.84km of 22kV power line connected to 110kV Chan May substation with total investment cost of 14 bil.VND. At the end of 2012, 220/110kV – 125MVA Hue 1 (E6) substation was energized, which ensured the power supply to Thua Thien Hue province. At the beginning of 2013, 110/22/6kV-2x25MVA Dong Lam substation at Phong An commune, Phong Dien district, Thua Thien Hue province was successfully energized, the substation mainly supplied power to Dong Lam Cement Factory and was connected to the national power system via 110kV Van Xa – Dong Ha power line. On 08/2015, 110/22kV-25MVA Phu Thanh (Hue 3) substation and branches were energized. On 01/12/2015, 110/22kV-25MVA Dien Loc substation and branches under Distribution Efficiency Project (DEP) project was energized. On 09/01/2016, 220/110-2x125MVA Hue 1 (E6) was upgraded from single transformer mode into double transformer mode and its distribution equipment was also upgraded synchronously (total investment cost was 61.2 bil.VND), which ensured stable and safe power supply, partly contributed to socio-economic development, secured defense security for Thua Thien Hue province in the following years. On 16/9/2016, the second circuit of 220kV Hoa Khanh - Hue power line with 82km of length was energized. This is one of the power transmission projects under tier-one energy projects, which was designed to connect hydropower plants located at the west of Quang Nam province and 500kV Da Nang substation in order to supply power to Thua Thien Hue and Quang Tri province. Apart from that, this power line is also for forming connection to A Luoi hydropower plant (at Hung Dien, Binh Dien of Thua Thien Hue province), Rao Quan hydropower plant, Quang Tri Thermal Power Plant. At the end of 2018, 220/110-125MVA substation, 01 110kV feeder bay at 110kV Phong Dien substation, 04 22kV feeders connected to the substation were energized with total investment cost of 159.2 bil.VND, which met the increasing demand of local load, reduced power losses, improved reliability in power supply, contributed to the development of local economy and ensured safe operation. In this period also, the Power Company received 27/36 communes of REII project and returned the loan, with the project scope including: 444.69km; 41,862 meters. From 2013-2018, the Power Company also received Loc Tien commune, Phu Loc district, Thuy Tan commune, Huong Thuy town, Phong An, Phong Son, Phong Dien district…. Along with receiving rural power network since 2009, Thua Thien Hue Power Company has also invested in: (i) 556 projects with the scope of work: 620km of MV power line, 1,004km LV power line, 873 substations with total capacity of 224.85 MVA with total planned capital of 1,094 bil.VND and (ii) 6 other big projects implemented by Central Power Corporation with total planned capital of 827.46 bil.VND, including: (ii.1) the Rural Electricity II project for Thua Thien Hue province (the original project) for LV network financed by the World Bank from 2009-2010 with total planned capital of 114.88 bil.VND; (ii.2) the Rural Electricity II project for Thua Thien Hue province (REII) for MV network financed by the World Bank from 2009-2010 with total planned capital of 35.36 bil.VND; (ii.3) the Rural Distribution project of Thua Thien Hue province financed by the World Bank from 2010-2012 with total planned capital of 143.66 bil.VND; (ii.4) the subproject for upgrading and expanding rural distribution network of Thua Thien Hue province financed by ADB from 2013-2015 with total planned capital of 157.66 bil.VND; (ii.5) the subproject for decrease of emission intensity in electric power supply financed by KfW (KfW2) from 2016-2018 with total planned capital of 170.8 bil.VND and (ii.6) the project of rehabilitation and development of MV/LV power network at districts, cities of Thua Thien Hue province financed by KfW (KfW3.1) from 2019-2019 with total planned capital of 205.1 bil.VND. So far, the power sector has supplied electricity directly to rural households at 143/152 communes, districts and towns, taking up 95.4%, there are 131,571/156,992 rural households directly purchasing electricity from the power sector based on the electricity tariff regulated by the government, taking up 83.8%. After receiving facilities, the power sector always pays attention and spends a lot of investment resources for constructing, rehabilitating, upgrading the power system for rural areas, which contributes to the cause of rural renovation… Average investment rate for power system during 2009-2019 for communes, wards, districts, towns of the province reaches 1.22 billion VND/commune year…
The joy when connecting Kan Hoa-Cu Muc village, A Luoi district into national power system in 2016.
During the course of 30 years of investment and development, so far, Thua Thien Hue Power Company has been managing: (i) 410 km of 110kV power line; (ii) 10 110kV substations with total capacity of 473MVA, which meets the provincial load demand (289MW); (iii) the estimated power sales reaching 1.85 billion kWh (increasing by 32.92 times in comparison with the provincial reconstruction period 1989); (iv) 4,957 km of MV/LV power line (increasing by 5.8 times); (v) 2,371 distribution transformers (increasing by8.72 time) with total capacity of 678.7MVA (increasing by 13.3 times); (vi) 302,963 customers (increasing by 14.52 times); (vii) 152/152 (100%) communes, wards, towns and 99.98% households connecting to power grid. MV power grid has been planned according to N-1 standard which ensures reliable power supply and interconnection between 110kV, 220kV substations. The power company has been operating 110kV remote control center for data acquisition, supervision and remote control of 09/10 110kV substations which have been transformed into unmanned substations. The power company is also the pioneer in expanding SCADA system for MV power grid and has been remotely controlled 195 nodes in the power grid. This system enables remote supervision, control and acquisition of data of equipment operating in the power grid, quick recovery of the grid in case of faults, an increase in labor productivity and minimizes outage period during maintenance. The power company also applies live line technology and bypass technology for MV/LV power grid and utilizes mobile transformers, generators for maintaining power supply to customers during maintenance and efficiently harness power grid database and assets via GIS system.
Author: Hung Son