H‑Infinity

The concept design stage sets the direction for the entire project. A well-executed electrical concept study defines the system architecture, identifies key equipment and layouts, establishes compliance requirements, and provides accurate cost estimates — all before detailed engineering begins. This is where we prevent costly redesigns downstream by getting the fundamentals right upfront.

01What is Initial Concept Design?

Initial concept design is the first formal engineering activity that translates project requirements into a workable electrical system architecture. It includes:

System Architecture

Define the overall electrical structure — voltage levels, source configurations, distribution scheme (radial, ring, or grid), and earthing approach.

Equipment Selection

Identify major equipment types (transformers, switchgear, generators) with preliminary ratings and specifications.

Layout Planning

Propose preliminary layouts for substations, switchrooms, cable routes, and equipment locations based on site constraints.

Cost Estimation

Develop Class 3 or Class 2 estimates (±15% or ±10%) to support project feasibility and investment decisions.

02Why Concept Design Matters

The concept design phase is where you have the most flexibility and the lowest cost to make changes. Decisions made here typically lock in 70–80% of total project cost:

▸Cost Certainty — An accurate concept estimate prevents budget overruns during detailed design and procurement.
▸Risk Mitigation — Early identification of site constraints, regulatory hurdles, and technical challenges avoids expensive rework later.
▸Stakeholder Alignment — A clear concept document gives owners, operators, and regulators a shared understanding of what's being built.
▸Regulatory Approval — Many jurisdictions require a completed concept/feasibility study before detailed design or construction permits can be issued.

03Our Approach

Our concept design process is iterative and collaborative, working closely with project stakeholders to develop an optimal electrical architecture:

1. Requirements Review

Analyse the project basis of design, electrical load profiles, site conditions, utility interconnection requirements, and regulatory framework.

2. Option Comparison

Develop 2–3 alternative electrical system architectures and compare them on technical merit, cost, constructability, and operability.

3. Preliminary Design

Develop single line diagrams, equipment schedules, preliminary layouts, and cable route plans for the selected concept.

4. Cost & Risk Assessment

Prepare engineering cost estimates and identify key risks with mitigation strategies for the concept phase.

04Scope of Concept Design

Our concept design deliverables provide everything needed to move to detailed engineering:

▸Single Line Diagram (SLD) — Preliminary SLD showing all voltage levels, sources, and major distribution paths.
▸Equipment Schedule — Preliminary specifications for all major equipment with ratings and quantities.
▸Layout Drawings — Preliminary sketches showing substation and switchroom locations, cable routes, and equipment spacing.
▸Load Summary — Consolidated load list with diversity factors, demand factors, and total connected/kW demand.
▸Cost Estimate — Class 3 estimate with equipment, materials, labour, and contingency breakdown.
▸Concept Report — Comprehensive document covering all above with recommendations and next steps.

05Standards & Compliance

✓IEC 60364 — Electrical Installations in Buildings

✓IEEE 141 — Red Book (Power Distribution)

✓ISO 15686 — Building Life Cycle Planning

✓AACE RP 18R-97 — Cost Estimate Classification

06Why H-Infinity

We've delivered concept designs for projects ranging from small commercial buildings to large industrial complexes and offshore platforms. Our concept studies don't just describe what's being built — they explain why each decision was made and what the alternatives were, giving you the confidence to proceed to detailed engineering with full clarity.

Initial Concept & Planning Design