https://www.vultr.com

The Everywhere Cloud

Deploy an instance.
Accelerate your application.


Generation - Scenario 1

By -
This post is inspired by Problem 36, Chapter 17 (Power Plant) of "Textbook-Reviewer in Electrical Engineering, 1st Edition" by Professional Electrical Engr. (PEE) Marcialito M. Valenzona.

SITUATION

An existing power plant has a maximum demand of 20MW. With a load factor of 55% and a capacity factor of 50%, what is its present reserve capacity?


ANALYSIS

1.) Average demand:

Load factor is the average demand over the maximum demand for a given operating period.

LF = demand,avg / demand,max
0.55 = demand,avg / 20MW
demand,avg = 20MW * 0.55
demand,avg = 11MW

2.) Maximum capacity:

Capacity factor is the average demand felt by the plant over the plant's maximum installed capacity.

CF = demand,avg / capacity,max
0.5 = 11MW / capacity,max
capacity,max = 11MW / 0.5
capacity,max = 22MW

3.) Reserve capacity:

Reserve capacity is the difference between maximum capacity and maximum demand.

capacity,rsv = capacity,max - demand,max
capacity,rsv = 22MW - 20MW
capacity,rsv = 2MW

CONCLUSION

The present reserve capacity of the power plant is 2 MegaWatts.

Note:

Load factor is different from (but related to) demand factor.

Demand factor is the maximum demand for a given operating period over the total connected load (including those not presently energized).

LF = demand,avg / demand,max
DF = demand,max / load,total

Comments

Post a Comment

Popular posts from this blog

Standards - Note 3

By -
Image
WIRE AMPACITIES, INSULATORS, AND IMPEDANCES Below are some useful tables pertaining to ampacities, insulators, and impedances of various wires. These are derived from the 2017 Philippine Electrical Code [ or the 2017 National Electrical Code ], but are rearranged in a manner that is easier to interpret and understand. 1.) Allowable Ampacities of Insulated Conductors in Raceway. The areas, ampacities, and insulation types of the following tables are based on 2017 PEC Table 3.10.2.6(B)(16) [ or 2017 NEC Table 310.15(B)(16) ]. 1.1.) Copper Wire Ampacities --------------------------------------- |  Copper  |  Insulation Max Op. Temp | --------------------------------------- |   Area   | 60degC | 75degC | 90degC | |   mm^2   |  Amps  |  Amps  |  Amps  | --------------------------------------- |    2.0   |    15  |    20  |    25  ...
Read more

Standards - Note 4

By -
Image
RACEWAY SIZES (CONDUIT AND TUBING) 1.) Raceway Sizing There are three options for sizing raceways according to 2017 PEC Table 10.1.1.1 [ or 2017 NEC Chapter 9 Table 1 ], based on cross-sectional areas: A.) 53% raceway area for 1 conductor (a multiconductor cable is treated as a single conductor [Note 9]) B.) 31% raceway area for 2 conductors C.) 40% raceway area for over 2 conductors 1.1.) Choosing Between Alternatives For future expansion purposes, option (A) is far from practical. This may have use in very specific installations that are assumed to be not needing any expansions, but upgrades will definitely happen and option (A) will eventually become a bottleneck. Option (B) for 2 conductors having a smaller area than either option (A) for 1 conductor or option (C) for over 2 conductors may seem nonsensical, but it actually does make sense. Having 2 conductors usually means 2 live wires supplying loads that may require an equipment grounding conductor ...
Read more

Faults - Scenario 4

By -
Image
This post demonstrates how to estimate the kiloAmpere Interrupting Capacity (kAIC) rating of the first circuit breaker at the secondary side of a transformer using the Infinite Bus Method. The method assumes infinite supply from the primary side with negligible line impedances. Below is a modified version of Example D13 (Available Short Circuit Current)  in Appendix D of the 2017 Philippine Electrical Code (PEC). SITUATION Two adjacent buildings are supplied by two different distribution transformers. One transformer is single-phase rated 100kVA, 230V with 2.5% impedance. The other is three-phase rated 100kVA, 230V line-to-line and also has 2.5% impedance. What minimum kAIC ratings are needed for the first circuit breakers down the line of each transformer to safely interrupt the maximum symmetrical fault currents? ANALYSIS 1.) SINGLE-PHASE TRANSFORMER LOAD-SIDE SUB-CIRCUIT Base Power, 1ph: S,base = 100kVA Base Voltage, 1ph: V,base = 230V Impedance, ...
Read more