400 kV OHTL Oradea – Bekescsaba

Short description:

The North-West area of Romania is characterized by power deficit. This area does not cope with the determinist criteria of sizing N-1 elements under operation. Under certain situations (peak of consumption, lack of fuel at the main power plant in the area Iernut TPP) if the OHTL 400 kV Sibiu-Iernut is not under operation a consumption area of about 1000 MW is not supplied representing damages of over 4 mill Euro/incident.
At present it is analyzed the opportunity of performing in Cluj area of a hydro-power plant with storage through high power pumping.
An interconnection line in the West part of Romania connected to the substation 400/110 kV Oradea represents a reserve of the line 400 kV Sibiu-Iernut-Gădălin through the branch Oradea-Roşiori-Gădălin and allows the maintaining of supply continuity in the consumption area Transilvania.

Supplied services:

The design of OHTL 400 kV of 97 km length between the substation 400/110 kV Oradea and the Romanian-Hungarian border:

performance of topometric measurements based on STEREO 70 system.
working out of technical documentation necessary for declaring the public utility investment as national interest investment.
working out of the basic design and technical specifications for organizing an international bid for the line erection.

Main technical characteristics:

OHTL 400 kV Oradea-Bekescsaba will have a length of 97 km, with 2 distinct trunks:

one simple circuit trunk between Oradea and Nădab of 74 km length to be performed of simple circuit steel towers “RODELTA” and “Y”;
one double circuit trunk between Nădab and landmark no.54 of the Romanian-Hungarian border of 23 km length to be performed on double circuit steel towers type DONAU, with a circuit equipped under the first stage.

The line will be equipped with 9 active conductors, three on each phase of aluminum-steel ALOL 300/69 mm2. For a phase formed of three conductors, spacers-dampers will be used.
The line will be equipped with 2 protection conductors all over the section out of which one with optical fibre type OPGW 95 and the other one of steel-aluminum type ACS 95 mm2.
The protection conductors will be connected at the grounding electrode having a resistance of maximum 10 W .
The line insulation will be performed with insulator chains equipped with insulators made of composite materials, of silicone rubber; the shielding of conductors is performed in the fixing places by means of suspension clamps through premoulded windings.
For all towers of OHTL 400 kV the foundations will be cast according to the geotechnical report and the floodability study.
The technical solutions adopted for OHTL 400 kV Oradea-Bekescsaba have in view the reduction of the line negative potential impact on environment by adopting some direct measures included in the investment general estimate (chapters 1 and 2) and some indirect measures included in the basic investment (chapter 4).
The value of direct and indirect measures for environment protection is 37.4 bill Lei (about 5.17/ of the investment value) and includes:

14.6 bill. Lei (arrangements for environment protection);
9.3 bill. Lei (access roads, protection LTc-ROMTELECOM (Telephone Company) and LTc-CFR (National Railways Company);
13.5 bill. Lei (expenses for reducing Corona losses in electromagnetic field).

Estimated technical performances:

The performance of the interconnection OHTL 400 kV Oradea-Bekescsaba offers the following advantages:
A) Safe supply of a large consumption area, of about 1000 MW.
B) Strengthening of the electric branch point Oradea leading to the increase of voltage stability in the area and accordingly to the reduction of power and energy losses.
C) Strengthening of the interconnection network in the West side of Romania and therefore the increase of electric power amount which can be transited between Romania and Hungary leading to higher financial compensations.
D) Improving of reliability and increasing the transmission service quality of both power systems
E) Reserving the existing line Arad-Sandorfalva, increasing the safety degree of fulfilling import/export contracts with the power European market.

Estimated economic efficiency:

Internal Rate of Return (IRR) 25%.
Profitability Index 2.016.
Net Present Value (NPV) 18.77 mill.Euro.
Present return time 6 years.

Client / Location:

The route of OHTL 400 kV Oradea-Bekescsaba is placed in Bihor and Arad counties being oriented towards North-South (for the section Oradea-Nădab), respectively East-West (for the section Nădab-Romanian-Hungary border).

Associated companies:

Fichtner – ROMELECTRO

Start Date / Completion Date:

July 2003
The basic design and technical specifications have been worked out and approved by Transelectrica.

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