Don’t Guess—Get It Right from Day One
Let me ask you something: Would you ever buy shoes without knowing your size? Probably not. Yet when it comes to solar systems in Pakistan, many people make that exact mistake. They jump in without understanding what Size solar System they actually need.
And guess what happens? Some overspend massively on oversized systems. Others go too small, ending up disappointed when the lights still go out during load shedding. I’ve seen it happen countless times—and that’s why I wrote this guide.
So, if you’re serious about switching to solar, let’s walk through how to size your solar system the right way.
Step 1: Know Your Energy Usage Like the Back of Your Hand
First things first: Grab your last 3 to 6 electricity bills. You’re looking for the number of units (kWh) consumed each month.
Let’s say your average monthly usage is 600 units. That’s about 20 units per day. You’ll need to generate around 20 kWh of electricity daily to cover your consumption — this becomes your target output.
Formula to estimate system size in kW:
Daily kWh usage ÷ Average sunlight hours/day
In Pakistan, we get around 5.5 sunlight hours/day on average. So:
20 kWh ÷ 5.5 = ~3.63 kW system
That means a 3.5 to 4 kW system would roughly match your usage. Sounds simple? It is — but only if you take time to calculate.
Step 2: Factor in Panel Efficiency and System Losses
Not all panels are created equal. A panel rated at 500W doesn’t give you 500W every hour. You lose energy due to:
- Temperature (hotter panels are less efficient)
- Dust and dirt (hello, Karachi air!)
- Inverter losses and wiring
That’s why experts recommend oversizing your solar system by 15–20%.
So, for that 3.5 kW system we calculated above, plan for around 4.2 kW to account for efficiency loss. This helps you avoid unpleasant surprises on cloudy days or dusty weeks.
Step 3: Plan for Current + Future Load
This is a mistake I made personally. I sized my solar system for my current load, but didn’t think about adding an AC later or expanding to a two-story home.
If you’re planning to install new appliances, EV chargers, or expand your home, size your system with a growth buffer.
Real-life example:
I recently helped a family in Lahore who had a 5 kW system installed 2 years ago. Today, they’ve added another floor and two ACs — now they need a 10kW upgrade. It would’ve been cheaper to install a larger inverter and prepare for expansion from day one.
Step 4: Consider Battery Storage (or Not)
If you’re going for a hybrid or off-grid system, don’t forget battery sizing. This is crucial if you want power at night or during load shedding.
Rough estimate:
A 5 kW hybrid system typically pairs well with a 7.5–10 kWh battery bank for basic nighttime needs (fans, lights, Wi-Fi).
But batteries are expensive, so get a professional to help optimize usage vs. cost.
Step 5: Get a Site Assessment — Not Just Quotes
Solar isn’t one-size-fits-all. Your roof angle, local weather, shading, and even your wiring setup matter. That’s why I always recommend getting a professional site audit before installing anything.
A good solar consultant will:
- Inspect your roof and shade levels
- Check your breaker box and wiring
- Evaluate your daily usage profile
- Suggest right-sized inverters, batteries, and panel brands
It’s like having a tailor measure you before stitching your suit — accurate, personal, and reliable.
Common Mistakes to Avoid (Seriously, Don’t Do These)
- Guessing system size based on your neighbor’s setup
- Buying a huge system just for “extra savings”
- Ignoring net metering and overproducing without benefit
- Skipping energy-efficient upgrades that reduce load
- Choosing the wrong inverter size (future upgrades become harder)
Conclusion: Size Smart, Save More
Getting solar is one of the smartest moves you can make in Pakistan right now — but only if you size it right. A mismatched system either burns your budget or leaves you powerless when you need it most.
And here’s the deal — you don’t have to figure this out on your own. We offer free consultations, tailored assessments, and fully optimized systems to make sure your investment gives the best returns, now and in the future.
Thinking of going solar? Let’s make sure you size it right from day one.
Contact us now for a custom Size Your Solar System consultation.
Also, if you’re curious about what actually affects your solar output, don’t miss our linked guide: Solar Panel Efficiency: What Factors Really Affect Performance?
