When considering commercial solar for your business, one of the most common questions we hear at Next Generation Solar is:
“Do I have enough roof space for it to make a difference?”
The good news is: you probably do. But how much you’ll need depends on the size of your system, your business type, and your energy goals. In this guide, we break it down by kilowatt (kW) requirements and typical roof space needed to help you understand what’s possible for your site.
How Much Space Does 1 kW of Solar Require?
As a general rule of thumb:
✅ 1 kW of solar panels requires around 6 - 7 square metres of roof space.
So, for example:
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50 kW system = approx. 300–350 m²
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100 kW system = approx. 600–700 m²
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250 kW system = approx. 1,500–1,750 m²
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500 kW system = approx. 3,000–3,500 m²
This assumes a pitched or flat roof with minimal shading and panels installed at optimal spacing. Our team will always carry out a full site assessment to maximise usable space.
System Size by Business Type (Typical Ranges)
| Business Type | Typical System Size (kW) | Approx. Roof Space Required |
|---|---|---|
| Small Retail or Office | 10–30 kW | 60–210 m² |
| Medium Warehouse | 50–150 kW | 300–1,050 m² |
| Car Dealership | 75–200 kW | 450–1,400 m² |
| Large Factory / Logistics | 250–500+ kW | 1,500–3,500+ m² |
| Multi-Site Organisation | 100–1,000+ kW total | Varies per site |
These figures will vary based on your energy usage, roof shape, and site constraints. Some businesses may use a combination of roof-mounted and ground-mounted systems where space allows.
Learn more about our Commercial Solar Solutions.
Flat vs Pitched Roofs
Most commercial buildings whether they’re warehouses, dealerships, or industrial units are ideal for solar due to their large, often flat roof areas.
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Flat roofs: Panels are installed at a fixed tilt using ballasted systems. These may require more spacing between rows to avoid shading, slightly increasing total area needed.
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Pitched roofs: Often more efficient for solar if correctly oriented, requiring less space overall for the same kW output.
Not sure what’s suitable? Our free assessment will evaluate your roof type, material, and capacity.
Should You Fill the Whole Roof?
Not always. At NGS, we design systems based on your actual energy usage, business hours, and long-term goals not just how much space you have.
In fact, oversizing a system may not always yield extra returns unless:
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You plan to add battery storage
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You want to supply EV chargers on-site
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You’re participating in export schemes like Smart Export Guarantee (SEG)
Example: Dealership Case Study
A leading UK dealership group partnered with NGS to install a 166 kW rooftop system, covering around 1,000 m². The system:
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Offset more than 40% of annual electricity usage
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Reduced carbon emissions by 29 tonnes/year
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Delivered ROI within 6 years
Learn more in our Dealership Solar Projects.
Ready to See What’s Possible?
Even if your roof isn’t huge, modern high-efficiency panels can produce more energy in less space than ever before.
With rising electricity prices and growing pressure to cut emissions, investing in solar is one of the smartest ways to future-proof your operations. And it starts with one question:
How much space do you really need?
Let us help you find out.
