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Design a Power Plant Electricity Allocator

Design a class-level system modeling a power plant that distributes electricity to multiple neighbourhoods, each with a stated demand, subject to the plant's total capacity.

1. Problem Statement

Design a system that models a power plant with a fixed electricity capacity distributing power to a set of neighbourhoods, each with a stated demand. The plant may not have enough capacity to fully satisfy all demands simultaneously. How would you design this?

2. Live Coding Format

Work in the provided coding workspace while explaining your decisions to the live interviewer. Validation may use inline tests, examples, comments, or a verbal walkthrough.

3. Key Focus Areas

  • 1
    PowerPlant / Neighbourhood entity decomposition
  • 2
    Allocation policy clarification when demand exceeds capacity
  • 3
    Capacity tracking and over-demand handling
  • 4
    Add/update/remove neighbourhood demand
  • 5
    Allocation query: actual delivered vs requested

4. What Strong Candidates Should Demonstrate

  • Model a constrained resource (total capacity) distributed across consumers (neighbourhoods with demand).
  • Clarify and choose an allocation policy — rather than assuming one — and implement it consistently.
  • Separate plant-level capacity tracking from neighbourhood-level demand representation.
  • Validate allocation correctness with concrete numeric examples.

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Practice this problem in the live coding workspace while the interviewer probes your clarification, implementation, trade-offs, and validation.

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Core Concepts

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Object-Oriented DesignResource AllocationClass Modeling

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