Solar Calculator UAE — What kW System Does Your Villa Actually Need?

Sizing a UAE rooftop system is the same arithmetic everywhere: monthly units divided by the units each installed kW produces in a month. The catch is that the second number is the one nobody in this market publishes. DEWA publishes its slab tariff and it publishes irradiation — "about 2100 kWh/m2 for Dubai" a year at the optimal south-facing 24° tilt — but irradiation is what falls on the roof, not what reaches your meter.

So the generation field below starts EMPTY. DEWA’s own FAQ tells you where to get the number: ask your provider "how much your new system will produce on an annual basis". Divide that by 12 and by the system kW, type it in, and the calculator works. Until you do, it prints nothing — which is the honest state of a UAE sizing question, not a bug.

Every field below is editable, and every default carries its source and date on the field itself — the defaults are a starting point, not a claim about your bill. We sell no hardware and take no installer commission; see how we verify.

5 fields on this page ship blank, on purpose

No source we can cite publishes these figures for UAE, so the fields start empty rather than pre-filled with something plausible. The calculator prints no result until you supply your own.

  • Units per month per installed kW — No UAE authority publishes a per-kW monthly yield. DEWA publishes irradiation, not output — "about 2100 kWh/m2 for Dubai" a year at the optimal south-facing 24° tilt — and its own FAQ tells you to ask your provider "how much your new system will produce on an annual basis". Put that contractor figure in here, divided by 12 and by the system kW. Everything below stays blank until you do.
  • Installed cost per kW — low (AED) — UAE rooftop solar is sold by quotation. The only figure DEWA publishes is dated by DEWA itself — "(Q2 2021) typical system costs are in the 4,500-5,000 D/kWp range for small ‘villa-size’ systems" — and a five-year-old band is not a 2026 default. Type the per-kW figure from your own quote.
  • Installed cost per kW — high (AED) — Same reason as the low figure: quote-only market, no current published band.
  • Price of one panel (AED) — No verified public AED price exists for a Tier-1 550W-plus module — that segment is sold by distributors who publish nothing. Consumer retail publishes smaller panels; check /ae/prices/solar-panels for the dated rows we do have and type the price from your own quote.
  • Usable kWh per panel per day — Follows from the yield figure above, which no UAE authority publishes. Ask your DEWA-enrolled contractor for the annual production estimate on the exact panel you are quoted, and divide by 365.

No result yet — generation per installed kW has no published figure for this market, so there is nothing to calculate from until you type your own. That is deliberate: a number we invented would look exactly like a number we verified.

How this calculator works — the actual arithmetic

  1. Generation: it uses whatever you type into the "units per month per installed kW" field. There is no UAE default because DEWA publishes irradiation ("about 2100 kWh/m2 for Dubai" a year at the optimal south 24° tilt), not delivered output, and its own FAQ directs you to your provider for the production estimate.
  2. System size = monthly units ÷ your generation figure, rounded up to the nearest 0.5 kW.
  3. Battery = (monthly units ÷ 30 ÷ 24) × backup hours × 1.25. The 1.25 covers depth-of-discharge and round-trip losses.
  4. Cost: only if you supply a per-kW figure. DEWA’s single published band is dated Q2 2021 by DEWA itself, so nothing is pre-filled — see what a UAE system actually costs.

Why there is no worked example on this page

There is no worked example on this page, and that is deliberate. A worked example reproduces the calculator’s own defaults, and the two defaults this calculator needs — generation per kW and installed cost per kW — do not exist for the UAE in any source we can cite. DEWA’s only published cost figure is dated by DEWA itself: "(Q2 2021) typical system costs are in the 4,500-5,000 D/kWp range for small ‘villa-size’ systems". A five-year-old band is a historical note, not a 2026 default, so it is quoted here and used nowhere.

The one figure this page will commit to is the tariff, because DEWA publishes it: 0.230 AED/kWh for the first 2,000 units a month, then 0.280, 0.320 and 0.380, plus a fuel surcharge of 0.060 AED/kWh in August 2026.

Sources for this market’s defaults

What this calculator does not know

  • It cannot see your roof. Orientation, tilt and shading decide the yield, and DEWA states the favourable orientation in the UAE is south at about 24° — a flat Dubai roof with a compromise layout will not hit the optimum.
  • It cannot see the capacity cap. Installed capacity under Shams Dubai "cannot exceed the applicable share of the Total Connected Load" per Section 2.2 of the Connection Conditions, and DEWA may impose a lower limit for grid reasons. Your enrolled contractor calculates yours; this calculator does not know it.
  • Dust is not a footnote here. DEWA warns that dust accumulation "reduce sensibly the efficiency of the panels" and recommends frequent cleaning — a soiling loss the arithmetic above ignores entirely.
  • It sizes for units, not for credits. Because DEWA credits surplus rather than paying for it, a system meaningfully larger than your annual consumption banks credit you may never spend.

Frequently asked

What size solar system do I need for a villa in Dubai?

Divide your monthly DEWA units by the units each installed kW produces per month on your roof. We do not print a default for that second number because DEWA publishes irradiation rather than output — its own FAQ tells you to ask your provider how much your system will produce annually. Put that figure in and the calculator sizes the system.

Is there a limit on how much solar I can install in Dubai?

Yes. Under Shams Dubai the installed capacity cannot exceed the applicable share of your premises’ Total Connected Load, as set out in Section 2.2 of the Connection Conditions, and DEWA may impose a lower threshold for grid-integration reasons. Your DEWA-enrolled contractor calculates the limit for your connection.

What does DEWA charge per kWh?

DEWA publishes a residential slab tariff: 0.230 AED/kWh for 0–2,000 kWh a month, 0.280 for 2,001–4,000, 0.320 for 4,001–6,000 and 0.380 above 6,000, plus a fuel surcharge of 0.060 AED/kWh in August 2026.

Why does this calculator show no cost estimate?

Because UAE rooftop solar is sold by quotation and the only installed-cost figure DEWA publishes is one it dates itself to Q2 2021. A five-year-old band is a historical note, not a 2026 default, so the cost fields are blank until you type the per-kW number from your own quote.

Guides that explain the numbers

Shams Dubai net metering, explained

How DEWA credits a surplus unit — and why it never pays cash for one.

The DEWA solar connection process

Three stages, six steps, and the enrolled-contractor requirement.

What a solar system costs in the UAE

Verified AED component prices, and the installed total nobody publishes.

Products this applies to

UAE panel prices (dated survey)

Every AED row we have, with the date it was observed.

UAE battery prices (dated survey)Inverters sold in the UAE

Run these next

Solar battery payback calculator

What a battery saves under Shams Dubai — and why, at a 1:1 export credit, the honest answer is nothing.

Net metering vs net billing calculator

What a Shams Dubai system is worth a month, split between the units you use and the units you bank as credit.

All calculators · How we verify a number · Corrections log