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IESCO Solar Calculator: Islamabad & Rawalpindi Net-Billing Audit

Engineered for Islamabad and Rawalpindi consumers under Islamabad Electric Supply Company (IESCO), featuring clean air clearance and 5.1 PSH.

5.4 Peak Sun Hours / Day Coastal haze • High year-round sun 0.78 summer derating (temp & dust) factored

Electricity Usage

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STEP 1

Monthly Bill Amount:

Rs.

Quick Presets:

Estimated Grid Units: ~780 units

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Household Appliance Load:

1.5-Ton Inverter AC

750W continuous @ 26°C Econ

Daily Running Hours:

1.0-Ton Inverter AC

550W continuous @ 26°C Econ

Daily Running Hours:

Ceiling Fans

55W (14 hrs/day)

Inverter Refrigerator

150W continuous

Deep Freezer

180W continuous

1.0 HP Water Pump

1100W (1 hr/day)

LED Lights & TV / Wi-Fi

150W (6 hrs/day)

Calculated Total: ~780 Units

Estimated Grid Bill: ~Rs. 48,000

Top Energy User: 1.5-Ton Inverter AC (58% of bill)

Rooftop Structure Type

Grid Meter Phase

Night AC Battery Storage

Run inverter AC during night loadshedding

Inverter ACs Running at Night 1 AC

Night Backup Required 8 Hours

Battery Chemistry

2026 Solar Impact Audit

-87% Bill Drop

Current Utility Bill

Rs. 48,000

Progressive tariff slabs

New Post-Solar Bill

Rs. 6,200

Residual grid charges

Monthly Net Cash Kept In Pocket: +Rs. 41,800 / month

Recommended System Architecture

Calibrated for Tier-1 580W N-Type Bifacial TOPCon Modules

ENGINEERING SPEC

Solar Array Capacity

6.4 kW

Rated DC capacity

580W Panel Count

11 Panels

580W Bifacial TOPCon

Inverter Sizing

6 kW Hybrid

48V Pure Sine Wave

Required Roof Space

308 sq ft (~1.4 Marla)

Clear unshaded south/south-west exposure

Structure Rating

12-Gauge Galvanized

130 km/h wind certified

Night AC Battery Bank: 2x 5.12 kWh LiFePO4 (51.2V 100Ah)

Optimal for continuous AC loads. 4,000+ deep cycle lifespan (approx. 10 years).

Financial Returns & Net-Billing Payback

2026 NEPRA MODEL

Estimated Turnkey Capex

Rs. 9.5L – 10.7L

Tier-1 Hardware & Labor

Monthly Savings

Rs. 46,947 / mo

Slab avoidance

Payback Period

~1.8 Years

55% annual ROI

5-Year Net Profit

Rs. 18.0 Lakhs

Cumulative net savings

2026 Net-Billing Energy & Tariff Balance

Solar Self-Consumption

~35% Solar Offset

Displaces top progressive retail slabs

Grid Export Credit (NAEPP)

~533 units (Rs. 11,460)

Wholesale credit @ Rs. 21.50/kWh

Net Post-Solar Bill

Rs. 15,977 / mo

Residual bill to local utility

2026 Net-Billing Calibrated: Direct daytime consumption immediately displaces top progressive slabs (~Rs. 45-60/kWh). Exported daytime solar is credited at the wholesale NAEPP rate (~Rs. 21.50/kWh), protecting payback horizons.

Budget Alternative: Daytime "Slab-Breaker" Setup 55% Lower Capex

If hybrid storage exceeds your upfront budget, install a smaller daytime system without night batteries:

Array Sizing

3.5 kW (6 panels)

Estimated Capex

Rs. 4.1L – 4.6L

Monthly Savings

Rs. 29,170 / mo

*Skips expensive batteries. Runs your household and ACs on solar during the day, dropping your grid consumption below 200 units to qualify for base tariff slabs.

Contractor Quotation Validator

Have a quote from a local installer? Verify if you're being overcharged.

BS DETECTOR

Quoted Size (kW)

Quoted Price (PKR)

System Scope

Solar Potential in Islamabad & Rawalpindi (IESCO)

Consumers in Islamabad sectors (F, G, E, Bahria Town, DHA) and Rawalpindi benefit from lower airborne particulate matter compared to central Punjab, ensuring higher solar yield per installed kilowatt.

Regional Grid Utilities

LESCO (Lahore) GEPCO (Gujranwala) PESCO (Peshawar)

Explore Solar Sizing Guides & Cost Breakdowns (Pakistan 2026)

Detailed engineering specs, monthly unit yields, 580W panel counts, and turnkey cost breakdowns by system capacity:

3kW Solar System →

5–6 Marla homes running fans, lights, fridge, & 1 inverter AC. ~350–420 units/mo.

5kW Solar System →

10 Marla homes running 2 Inverter ACs + household load. ~600–750 units/mo.

10kW Solar System →

1 Kanal residences with 3–4 ACs & net-metering. ~1,250–1,500 units/mo.

15kW – 20kW Systems →

Commercial plazas, schools, clinics, & large joint families. ~2,000–3,000+ units/mo.

Solar Panels for AC Guide Lithium LiFePO4 Battery Guide Contractor Quotation Validator Free Embeddable Calculator Widget

Frequently Asked Questions (Solar Sizing & NEPRA Tariffs)

How long does IESCO net-metering take in Islamabad?

IESCO net-metering typically takes between 4 to 8 weeks from the date of application submission by an AEDB-accredited installer to bidirectional meter commissioning.

What is the solar irradiance in Islamabad & Rawalpindi?

Islamabad enjoys clean atmospheric clearance with an average of 5.1 Peak Sun Hours (PSH) per day, resulting in exceptional yearly kilowatt-hour generation.

Does CDA allow elevated solar structures in Islamabad?

Yes, the Capital Development Authority (CDA) permits rooftop solar mounting structures provided they adhere to height restrictions and do not violate building setback bylaws.