Chapter-2

POWER SUPPLY SECURITY PLANNING STANDARDS

1.       OBJECTIVE

Power Supply Planning is to aim at a least cost generating capacity expansion planning to serve the demand at a specified level of reliability.

2.       POWER SUPPLY PLANNING

Long term power supply planning shall be made based on Load Forecasts prepared pursuant to Condition 19.10 of the Haryana Transmission and Bulk Supply License. The Licensee shall abide by conditions of GRIDCODE in formulating its long-term load forecasts. The planning process shall take into account the existing contracted generation capacity, allocation from Central Sector Generation in the base year and from any future committed project and evolve the net additional requirement of power over the years during the plan period. The planning process shall also consider an extended study period of twenty years beyond the study period of ten years to smoothen out the "END Effects" due to different types of generation capacity at the end of the study period.

 3.       PLANNING CRITERIA

 3.1     Peaking Availability

The peaking availability of existing Hydro Electricity Plants and Thermal Plants shall be in accordance with data furnished by the respective Generating Companies and also as per the Power Purchase Agreements made with respective power stations. Availability from Central Sector Plants shall be taken as allocated by the Government of India. For the new plants, peak availability shall be as per Central Electricity Authority norms or as per the power purchase agreements with the respective Generating Companies.

3.2      Plant Availability, PLF and Outage rate

The following norms for plant availability and PLF shall be used in the simulation studies

The following outage rates for plants shall be used in the simulation studies.

[Note: i) Units commissioned before 01.04.1998 shall be considered as old units.]

3.3        Auxiliary Consumption

Auxiliary consumption in plants for the purpose of planning studies shall be follows:

3.4        Heat Rate

Gross heat rates for the generation units for the purpose of planning studies shall be used as follows:

Note: In case of any difference, the actual heat rate as specified by the Generating Company shall be adopted.

3.5   Secondary fuel oil consumption @ 3.5 ml / kWh shall be taken for coal based plants.

3.6    Economic Parameters

3.6.1 The cost estimate shall reflect economic conditions as on 1st April of the Base Year. The cost shall increase overtime at the rate of general inflation and shall exclude taxes and duties in so far as they are common in the economic evaluation. If the costs are considered to be financial costs, all taxes and duties shall be included

3.6.2   Plant Economic Life

The economic life of Generating plants may be assumed as follows for the planning studies in accordance with Govt. of India notification made under sub paragraph (A) of Paragraph VI of VI Schedule to Electricity (Supply) Act, 1948, from time to time.

3.6.3   Cost of Unserved Energy

Value of unserved energy (i.e. the loss to the economy if a KWh of energy required by consumers cannot be supplied) shall be considered in the economic analysis for the least cost generation expansion plan. Suitable pricing for such power outage costs shall be adopted from available studies applicable to Haryana.

3.7    Evaluation of Planning Studies

3.7.1  Suitable computer aided programming model/ program shall be adopted to arrive at a least cost generation expansion plan.

3.7.2  The economic evaluation shall be carried out in accordance with the guidelines enumerated below

  i.        Set out different generation expansion scenario incorporating available proposals mixed hydro/thermal expansion, only thermal expansion, mixed base/peak generation expansion, in the context of demand forecast.

  ii.         For each scenario, determine through simulation, the timing of new installations during the planning period in order to meet the planning criteria.

 iii.        Simulate the system operation in order to obtain the average annual energy production from each hydroelectric plant and each thermal plant.

 iv.        Compute the cumulative present value cost for the scenario over the planning period incorporating capital costs for new generation and associated transmission, fixed and variable operation and maintenance costs, fuel costs and unserved energy costs.

 v.         Compare the present value cost of each scenario with that of the other to arrive at the least cost scenario.

vi.         Calculate the Long Run Marginal Cost for the least cost scenario as follows:

a.  For each year of the plan period determine incremental cost of generation, transmission, energy requirement, energy generated, unserved energy, incremental net energy generated, loss of load probability in hours, unserved energy percentage.

b.   Work out the incremental cost of generation to the Net Present Value.

c.   Long Run marginal cost in Rs/KWh is = [Total net present value of incremental cost of generation and transmission (Rs.)] / [Incremental net energy generation (KWh)].

4.      POWER SUPPLY SECURITY STANDARDS

To ensure that the generation reserve is sufficient so that the system can meet the load considering  scheduled maintenance of all the units in the system and  forced outage of one largest unit in the system or in the event of non-availability of adequate hydro-electric generation capacity during the dry period, adequate reserve capacity shall be built into the system both for capacity and energy.

4.1     Capacity Reserve

Loss of Load Probability (LOLP) of 2% shall be used for planning models. This shall mean that for 2% of the time of the year (i.e., up to 175 hours/year) there is a probability that the system demand exceeds the available capacity. The required capacity would be adequate to meet the power supply security standards. However, optimal LOLP may be calculated for the Haryana System.

4.2   A contingency reserve margin equal to 5% of the system peak load, besides normal reserve margin corresponding to 2 % LOLP and 0.15% ENS shall be planned to take care of fluctuations in the availability of Hydro Electric generation during the critical period of February to June of a dry- year, and to account for outages of units, power station equipment, non-availability of Central Sector share in order to maintain security and integrity of the system.

4.3     Energy Reserve

"Energy Not Served'' shall be limited to 0.15% of the average annual energy demand.