--- title: "T/F: loop arrangement in urban area economical" subject: "Transmission and Distribution System Design" chapter: 5 key: "semester_8/transmission_and_distribution_system_design:tf-loop-urban-economical" source: https://www.bctengineer.com/q/semester_8/transmission_and_distribution_system_design/tf-loop-urban-economical site: BCT Engineering --- # T/F: loop arrangement in urban area economical Transmission and Distribution System Design · Chapter 5: Electric Power Distribution - Asked in: 2077 Chaitra, 4 marks - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_8/transmission_and_distribution_system_design/tf-loop-urban-economical - Whole chapter: https://www.bctengineer.com/md/semester_8/transmission_and_distribution_system_design/chapter-5 ## Question State and justify whether the following statement is TRUE or FALSE: The loop arrangement of distribution feeder in urban area is relatively economical than rural area. ## Short answer TRUE. Loop feeders require extra conductor and switches; in urban areas, high load density and short distances to close the loop result in low cost per kW served, while improved reliability and voltage regulation justify the investment. In rural areas, long distances for few loads make loops uneconomical. ## Answer **TRUE.** A loop (ring) feeder needs extra conductor to close the ring and extra switches to sectionalize it. Its cost is justified by the load it serves and the reliability it adds. - **Urban area:** the load density is high and the load points are close together, so the extra length needed to close the loop is **short**. The added cost per kW served is small. Urban consumers (commercial, hospitals, offices) also lose a lot from outages, and the loop reduces outage time and losses (current flows from both sides, so the voltage drop is lower). The extra cost is therefore quickly recovered. - **Rural area:** the loads are small and scattered over long distances. Closing a loop may need many extra km of line for a few kW of load, so the cost per kW is very high. The value of the energy saved from shorter outages is low. A simple radial feeder is more economical there. | Point | Urban | Rural | |---|---|---| | Load density | High | Low | | Extra length to close the loop | Short | Long | | Cost per kW of the loop | Low | High | | Value of reliability | High | Low | So the loop arrangement is relatively more economical in urban areas than in rural areas. ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. The statement that a loop feeder is relatively more economical in urban areas than in rural areas is: A. False, because urban areas have scattered loads B. True, because the extra cost of the loop is small per kW served in urban areas C. False, because loops are cheaper than radial feeders everywhere D. True, because rural areas need no reliability Answer: B. In dense urban areas the extra length to close the loop is short, so the added cost per kW is small. (Key point: Verdict) 2. Why is closing a loop costly in a rural area? A. Load points are far apart, so many extra km of line serve few kW B. Rural loads are very large C. Loops need no switches in rural areas D. Rural voltage is always higher Answer: A. Scattered small loads over long distances make the cost per kW of the loop very high. (Key point: Extra length to close loop) 3. What additional benefit helps recover the cost of an urban loop quickly? A. Outages become longer B. Urban consumers lose little from outages C. Loop reduces outage time and losses because current flows from both sides, and urban outages are costly D. Loop removes the need for any protection Answer: C. Commercial and critical urban consumers lose a lot in outages, and two-side feeding lowers voltage drop and losses. 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