Ensuring reliability and repair work

Reliability

Ensuring reliable power supply of consumers is an unconditional strategic priority of Lenenergo. The indicators of reliability are included in the number of key performance indicators of the Company.

In order to improve the reliability of power facilities Lenenergo has been implementing the following programs:
Target program	Implementation of the program	Effect of the program implementation
Installation of reclosers on OTL 6-10 kV (pcs.)	79	Time reduction for elimination of technological failures on power lines 6-10 kV by increasing the efficiency of fault location on power lines
Expansion of glades for OTL (hectare)	1,683	Enhancing reliability, reducing the number of outages associated with falling trees
Replacement of oil switches 6-10 kV	54	Replacement of oil-filled equipment
Replacement of overloaded power transformers and reconstruction of single-transformer substations (MVA)	456	Eliminating the occurrence of overloading of transformers in the N-1 mode. Formation of capacity reserves
Replacement of non-insulated wires with SIW (km)	246	Enhancing reliability
Strengthening of networks 0.4-10 kV on cable grid (MVA)	14	Removal of network restrictions on the possibility of connection to electric networks
Strengthening of networks 0.4-10 kV on cable grid (km)	42	Elimination of not maintainable cable lines
Compensation of capacitive currents (object)	2	Implementation of the Operating Rules requirements

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Dynamics of technological failures (accidents):
Indicator	2012	2013	2014	2014/2013,%
Failures investigated by the commissions of Rostechnadzor	2	1	0	–100
Failures investigated by the commissions of Lenenergo	6,973	6,884	3,941	–43
Undersupply of electricity, thousand kWh	1,833.85	1,824.44	1,463.43	–20
Economic damage, RUB mln	40.883957	35.523572	78.085885	120
Average interruption duration per customer, hours	5.3	5.0	3.4	–32
System Average Interruption Duration Index, p.p.	0.019046688	0.018368519	0.006525026	–64

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Breakdown of tehnological failures (accidents) by organizational grounds in 2014, %

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The main reasons for failures are as follows:

aging, wear of equipment,
previous mechanical damage,
adverse weather conditions.

Repair program

The repair program of Lenenergo is annually developed on the basis of long-term plans schedules of repair of the equipment, analysis of the condition of power lines 0.4–110 kV, main and auxiliary equipment of substations, acts of inspection, instructions of supervisory bodies and identified risks to the reliability of electric distribution networks.

Breakdown of repair costs by main directions and ways of implementation of work in dynamics, RUB mln
Indicator	2012	2013	2014	2014/2013,%
OTL 110-0.4 kV	229	278	361	30
CL 110-0.4 kV	405	571	347	–39
Equipment of substations	442	412	461	12
Buildings and constructions	130	220	170	–23
Other objects	17	19	20	3
Total repair costs	1,221	1,500	1,359	–9
Including by:
economic method	314	342	344	0.6
contract method	907	1,158	1,015	–12

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Dynamics of expenses on repair program on the way of implementation, RUB mln

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Dynamics of expenses on repair program by key directions, RUB mln

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In 2012-2014, there was an increase in financing of repair works of overhead transmission lines and equipment of substations by reducing the funding of repair works of cable lines, buildings and structures, and other repairs. The growth of repair cost of overhead lines was largely due to the transition from 2014 to clearing of glades by the method of continuous mulching. This method is more expensive than usual mechanical cleaning of glades, but it helps to ensure the patency of glades for electrical staff (for operative performance of emergency recovery operations and current maintenance), as well as compliance with the rules of fire safety in the woods.

The volume of renovation of cable lines was due to the achievement of optimum values of the indicator “Damaged cable lines”. According to the results of implementation of the repair program in 2014 this indicator was 150 cable lines that enables to provide the necessary level of reliability of the cable network in St. Petersburg.

The dynamics for 2012-2014 demonstrates both increase in volume of work and its reduction. The amount of equipment to be repaid may increase or decrease in accordance with the long-term schedules.

Actual performance of the repair program in 2014 in comparison with the plan
Name	Unit	Plan	Fact	Execution of the annual plan, %
Substations 35-110 kV	Pcs.	15	16	107
Transformer substations 10/0.4 kV	Pcs.	1,718	1,762	103
Oil switches 35-110 kV	Pcs.	158	160	101
OTL 110 kV	km	585	589	101
OTL 35 kV	km	360	423	118
OTL 10 kV	km	2,268	2,261	100
OTL 0.4 kV	km	1,168	1,184	101
Clearing of glades	hectare	4,145	3,764	91
Total repair costs	RUB mln	1,365	1,359	100

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In 2014, the Company spent RUB 1,358.7 mln on the repair program, including RUB 344.2 mln for repairs by economic method, and RUB 1,014.5 — by contract method. Indicators of the repair program in 2014 were executed for 100% and above. The works on clearing of glades for overhead lines on wood-handicraft were executed completely.