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5th year peak load from consumer survey

Short answer

Electrified consumers are 70% of potential; monthly consumption grows 5% yearly for 5 years (×1.276). Daily energy = monthly / effective days; peak per consumer = daily/(24×LF). Class peak × contribution factor yields contributions. Summing gives a 5th-year peak of 17.1 kW.

From the initial survey of particular load center, the following data has been obtained.

Consumer classPotential consumerAvg. monthly consumptionNo. of effective days/month5th year contribution factor to peak5th year load factor
Domestic10030 kWh301.00.25
Commercial2030 kWh250.50.30
Non-commercial5020 kWh200.10.25

Assuming consumption growth factor of 5% in each year for each class and electrification coverage factor by 5th year is 70% for all, determine 5th year peak load of the load center in kW.

The 5th-year peak load of the load center is the sum of each consumer class's own peak, multiplied by its contribution (coincidence) factor to the system peak.

Method

For each class:

  1. Consumers electrified by the 5th year: N5=coverage×Npotential=0.7NN_5 = \text{coverage}\times N_{potential} = 0.7N.
  2. Monthly consumption per consumer in the 5th year, with 5% growth per year compounded over 5 years:
E5=E0(1+0.05)5=1.27628 E0E_5 = E_0(1+0.05)^5 = 1.27628\,E_0
  1. Daily energy per consumer:
Ed=E5effective days per monthE_d = \frac{E_5}{\text{effective days per month}}
  1. Peak demand per consumer, using the load factor:
Ppeak=average demandLF=Ed24×LFP_{peak} = \frac{\text{average demand}}{LF} = \frac{E_d}{24\times LF}
  1. Class peak =N5×Ppeak= N_5\times P_{peak}. Its contribution to the load-center peak = class peak × contribution factor.

Domestic class (sample)

N5=0.7×100=70E5=30×1.27628=38.288 kWh/monthEd=38.288/30=1.2763 kWh/dayPpeak=1.276324×0.25=0.2127 kWClass peak=70×0.2127=14.890 kWContribution=1.0×14.890=14.890 kW\begin{aligned} N_5 &= 0.7\times100 = 70\\ E_5 &= 30\times1.27628 = 38.288\ \text{kWh/month}\\ E_d &= 38.288/30 = 1.2763\ \text{kWh/day}\\ P_{peak} &= \frac{1.2763}{24\times0.25} = 0.2127\ \text{kW}\\ \text{Class peak} &= 70\times0.2127 = 14.890\ \text{kW}\\ \text{Contribution} &= 1.0\times14.890 = 14.890\ \text{kW} \end{aligned}

All classes

ClassConsumers by 5th yrMonthly kWh in 5th yrDaily kWhPeak per consumer (kW)Class peak (kW)CFContribution (kW)
Domestic7038.2881.27630.212714.8901.014.890
Commercial1438.2881.53150.21272.9780.51.489
Non-commercial3525.5261.27630.21277.4450.10.744

5th-year peak load

Ppeak,5=14.890+1.489+0.744=17.12 kWP_{peak,5} = 14.890 + 1.489 + 0.744 = 17.12\ \text{kW}

Answer: the 5th-year peak load of the load center is about 17.1 kW. If the survey year is counted as year 1, so that growth applies for only 4 years, the result is 17.12/1.05=16.3117.12/1.05 = 16.31 kW.

✓ Answer checked by Claude Opus 5.5 (high effort)

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