DEWA Load Schedule & Load Calculation Requirements

What Is a DEWA Load Schedule and When Is It Required

A DEWA load schedule is the quantitative backbone of every electricity supply application in Dubai: a table, backed by drawings, in which you declare the total connected load (TCL) of the installation, the maximum demand (MD) expected after diversity, and how that load is distributed across phases, distribution boards and final circuits. DEWA uses it to size the service connection, the metering arrangement and, on larger projects, the transformer or substation provision.

You need one for every new connection, every supply upgrade and every temporary construction supply that will convert to permanent — villas, towers, commercial and industrial buildings, warehouses, and fit-outs that increase a tenancy’s connected load. The schedule goes through the DEWA e-services portal inside the design approval package and is reviewed before any NOC or supply approval is issued.

The governing documents are the DEWA Regulations for Electrical Installations 2017 — BS 7671 with Dubai amendments — and the Dubai Building Code 2021, Part G. The network is 230/400V, 50Hz, TN-S at the point of supply. Every figure on the schedule must reconcile with the single-line diagram, DB schedules and floor plans; an internally inconsistent package is the fastest route to a review comment and a two-to-four-week resubmission cycle.

TCL vs Maximum Demand: Definitions and Diversity Factors

TCL is the arithmetic sum of every rated load in the installation — equipment, sockets, light points — in kW or kVA. It is an inventory figure. Maximum demand is the highest load you reasonably expect simultaneously, and it is the number DEWA actually sizes the service cable, main breaker and transformer on. MD is always below TCL; diversity explains the gap.

Diversity factors reflect that not every load runs at full rating at once: lighting in empty rooms is off, compressors cycle, domestic kitchen appliances rarely run together. DEWA expects the MD calculation to show a diversity factor per load category — lighting, small power, air conditioning, water heating, motors, lifts — with a stated basis. Factors from recognised practice (IET guidance, the BS 7671 On-Site Guide) are accepted; one unexplained global factor across the building is not.

The chain reviewers expect: per-circuit load → per-DB load → per-DB MD after category diversity → building MD after inter-board coincidence → service size. Every step must be traceable. Aggressive AC diversity is the classic trigger: cooling dominates in Dubai, and an unexplained 0.4 factor on the chiller plant will earn a comment.

• TCL — sum of all nameplate loads, per phase and per board.
• MD per DB — category loads times stated, defensible diversity factors.
• Building MD — sum of board MDs with an explicit coincidence allowance.
• Service rating — main breaker and cable on building MD plus a declared spare margin.

Documents and Drawings That Must Accompany the Load Schedule

The schedule never travels alone. A submission package includes the single-line diagram from service intake to final DBs with breaker ratings and cable sizes; a DB schedule per panel listing every circuit with load, breaker, conductor and earth-fault protection; architectural plans marking panels, metering rooms, risers and major equipment; and the written load calculation with the diversity logic spelled out. Projects that trigger a dedicated substation add the substation layout, ventilation, access and civil coordination drawings; fit-outs add the landlord NOC and the tenancy’s existing sanctioned load.

Two consistency rules catch more applicants than any technical error. Equipment counts must match the drawings — if the ceiling plan shows 240 downlights, the lighting line cannot assume 200. And the metering arrangement on the single-line diagram must match the category your connected load falls into, because metering requirements change at defined load thresholds.

• Single-line diagram, intake to final DBs, with protection ratings.
• DB schedule per panel: circuit, kW, breaker, conductor, protection.
• Plans: panel and metering room locations, risers, major equipment.
• Written calculation: TCL, per-category diversity, MD, phase balance, spare capacity.
• Fit-outs: base-build approval reference and existing tenancy load.

Load Thresholds That Change the Rules (PF correction 0.95 lagging, sub-metering ≥100 kW, chiller/motor limits)

Several DEWA requirements are dormant below a given load and mandatory above it. Know where the thresholds sit and state clearly which side your project is on.

Power factor first: DEWA Regulations require the power factor at the point of supply to be maintained at 0.95 lagging or better. Commercial and industrial installations with chillers, pumps, lifts or large motor groups almost always need automatic capacitor banks — with detuning reactors where harmonics are present. State the design PF, the kVAr compensation and the bank’s stage arrangement on the schedule.

Metering second: new connections fall under DEWA’s smart metering regime, and sub-metering is expected at substantial connected loads — the commonly applied threshold is 100 kW and above — so major load groups or tenancies can be metered separately. In multi-tenant buildings this drives the whole metering architecture. Declare the metering hierarchy on the single-line diagram, not in a covering email.

Motors and chillers third: DEWA Regulations restrict direct-on-line starting above defined motor ratings, so significant motor loads need soft starters or VFDs. District cooling versus on-site chillers changes the load picture fundamentally — a district-cooled building shifts its largest load to chilled-water pumps and AHU fans, and reviewers expect to see that reflected.

• PF ≥ 0.95 lagging at the supply point — state design PF and capacitor bank kVAr.
• Sub-metering expected at 100 kW connected load and above — show the metering hierarchy.
• DOL starting restricted above defined motor ratings — specify soft starter or VFD.
• Declare district cooling vs on-site chillers; show the resulting largest load group.

The 6 Most Common Load Calculation Rejection Reasons

Review comments on load schedules are remarkably consistent. Six causes account for most rejections. First, inconsistent totals: the summary TCL does not match the DB schedules, or the single-line diagram shows a different main breaker than the MD implies — generate the summary from the DB schedules, never by hand. Second, unjustified diversity: a blanket 0.5 across all categories, or AC diversity that assumes half the cooling plant is off in August — use per-category factors with a stated reference.

Third, missing power factor treatment: no design PF, no capacitor bank, or kVAr sized on nameplate motor load instead of corrected MD. Fourth, phase imbalance: single-phase loads lumped on one phase of a three-phase board — balance circuits across L1/L2/L3 and show per-phase totals. Fifth, metering mismatches: the load crosses a threshold (sub-metering at 100 kW and above, or a supply category change) but the diagram shows the old arrangement. Sixth, no spare capacity narrative: a main breaker sized to exactly the MD, or spare ways not reflected in the schedule — state a margin, typically 10–25% depending on building type and expansion plans.

Fit-Out Load Upgrades

Fit-outs are where load schedules go wrong most often, because the designer inherits constraints they did not create. Every tenancy sits inside a building whose total load was approved at base-build stage; your application is judged against the remaining allocation, not against what the riser could physically carry.

Start before design: get the tenancy’s sanctioned load and the landlord’s confirmation of spare capacity at the floor DB or metering point. The fit-out schedule then declares the incremental connected load — lighting, small power, supplementary AC, server loads — and the tenancy’s new MD. If the increment exceeds the existing allocation, the application escalates: DEWA may require a supply upgrade, pulling in the landlord, the base-build consultant of record and sometimes a building-level load restudy.

Reuse base-build drawing numbering so reviewers can trace your DBs to the riser; state which existing circuits are retained, modified or abandoned; never treat spare capacity in a landlord panel as yours — it belongs to the building’s approved MD. Restaurants, gyms, clinics and data-heavy offices are the classic escalation cases: dense process loads, low real diversity. Justify their diversity factors as carefully as the base numbers.

Verify your design against the regulation

Load schedule review is a compliance exercise: every declared figure exists because a DEWA regulation, a Dubai Building Code provision or a supply condition requires it. The designers who clear review in one cycle can trace every number to the requirement behind it — and check that trace before the reviewer does.

That traceability is what SparkProof is built for. Ask whether your diversity basis, PF correction, metering arrangement or fit-out upgrade path complies, and it answers with citations from the DEWA Regulations for Electrical Installations 2017 and the Dubai Building Code — actual clause text, not paraphrase, including which side of each threshold your declared load sits on.

FAQ

Frequently asked questions about DEWA load schedules and load calculation requirements in Dubai.

Frequently asked questions