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No Of Solar Panels

How many solar panels do you need?

If you’re considering making the switch to clean, renewable solar energy for your home, you may be asking: “How many solar panels do I need?”

It’s true there is no one size fits all answer so here we’ll cover some of the basics to give you an idea of how many solar panels you’ll need to make the most free electricity.

First things first, why go solar in the first place?

The two biggest reasons people choose to go solar is firstly it’s the eco-friendly choice. Solar power is 100% renewable, generates no greenhouse gases and will never run out.

Secondly, solar power can save you big bucks on your electricity bills as you’ll not be drawing as much if any energy from the grid. Plus, with various tax credits and incentives available, getting solar installed in your home could be cheaper than you think. Check out our latest guide to the grants available and see if you could be eligible HERE .

Let’s get back on track, how many solar panels should you get?

Well, this depends on several factors, including your energy consumption, the amount of sunlight your area receives, and the size of your roof (or the available space for ground-mounted panels).

How many solar panels do you need? What to consider

1. Energy Consumption: The Biggest Factor

The number of solar panels you’ll need primarily depends on your household’s annual energy consumption. The more electricity you use, the more panels you’ll need to offset that usage.

Average UK Home: Consumes around 2,900 kWh of electricity per year, requiring about 10 solar panels (a 3.5kW system).

Smaller Homes (1-2 bedrooms): Use around 1,800 kWh annually, needing 5-8 panels (1.75-2.8kW system).

Larger Homes (4-5 bedrooms): Use up to 4,100 kWh per year, requiring about 16 solar panels (5.6kW system).

2. Solar Panel Output

The output capacity of the solar panels also matters. Most residential panels in the UK are rated between 300-400 watts. For example, a 350W panel can generate approximately 265 kWh of electricity per year under ideal conditions.

3. Roof Characteristics

Your roof’s orientation, tilt angle, and available space can impact the number of panels you can install. South-facing roofs angled at 30-40 degrees get the most optimal sunlight. Shading from trees or buildings and limited roof area can reduce the number of panels possible.

Contact Warma UK and we’ll conduct a professional assessment of what your roof is capable of.

4. Budget Considerations

Larger systems with more panels come with a higher initial investment but offer the biggest payback.

5. Other Factors

Additional factors like solar batteries for energy storage can impact your decision on system size. Your personal motivations (environmental, financial, etc.) also play a role in determining the optimal system size. 

Want to maximise your savings? Get in touch with Warma UK for expert advice on solar systems and grants! Click on the link below to check whether you are eligible for a free solar panel grant along with insulation and heating.

See if you're eligible for free solar panel grant

See if you're eligible for free solar panel grant

Number of Solar Panels Based on Household Size 

Household Size  

Annual Energy Use  

Solar Panels Needed (350W)  

Solar Panels Needed (450W) 


1-2 People  

< 2,000 kWh  

2-6 panels  

2-4 panels 


2-3 People  

2,000 – 4,000 kWh  

6-11 panels  

4-6 panels 


4-5 People  

4,000 – 6,000 kWh  

11-16 panels  

7-9 panels 


5+ People  

6,000 – 8,000 kWh  

16-21 panels  

10-15 panels 


Remember, these are rough estimates from Energy Saving Trust. Your actual solar panel requirements could be higher or lower depending on your specific energy usage patterns, the system’s performance, and other site-specific factors. Need a more accurate estimate? Schedule a consultation with Warma UK! 

Roof Space Required for Solar Panel Systems 

System Size  

Number of Panels*  

Roof Space Required 



4 – 5  

8 – 10 m² 



6 – 8  

12 – 16 m² 



8 – 10  

16 – 20 m² 



10 – 13  

20 – 26 m² 



13 – 16  

26 – 32 m² 


*Assuming 350W – 450W panels which are typical for residential installations in the UK. 

A few key points on roof space requirements: 

  • The roof space needed is directly proportional to the system size (kW capacity) and number of solar panels. 
  • As a general rule of thumb, each solar panel requires around 2m² of roof space. 
  • For an average 3-bedroom house needing a 3kW system, around 16m² (8 panels) of roof area is required. 
  • A 4kW system with 10 panels would need 16-20m² of roof space. 
  • Larger homes may require 5-6kW systems taking up 20-32m² of roof area. 

However, it’s important to note that the actual roof space available can vary significantly based on the specific roof dimensions, orientation, tilt angle, and potential shading issues at the property. 

How Solar Batteries can help you save even more! 

Installing a battery storage system alongside your solar panels can significantly enhance your energy efficiency.  

A typical home battery system can store anywhere from 4kWh to 15kWh of electricity. This allows you to store excess power generated during the day for use during peak hours or at night, reducing your reliance on the grid. For instance, a 10kWh battery can power an average UK home for about 10 hours on stored energy alone. 

In addition, you can sell any excess power back to the National Grid via the Smart Export Guarantee (SEG). The SEG ensures you get paid for every unit of electricity you export, rates vary so check with your supplier to make sure you’re getting the best deal. 

Want to explore solar battery options? Warma UK can help you design the perfect solar system with battery storage! Call us on 01874 442 861 and let us show you how we can supply and fit a solar battery solution for a lot less than you think! 

How Can Warma UK Help You? 

At Warma UK, we can help you every step of the way with your solar installation. Our team will assess your specific situation and provide a tailored recommendation. Plus, we assist in securing solar grants, making the transition to solar power more affordable for you. 

Why Choose Warma UK? 

  • Expert Assessment: We evaluate your energy consumption, roof characteristics, and budget to recommend the ideal solar system for your home. 
  • Solar Grants: We help you access available grants and incentives to reduce your upfront costs. 
  • Professional Installation: Our team ensures a smooth and efficient installation process. 
  • Ongoing Support: We’re here for any questions or maintenance needs after installation. 

Ready to make the switch to solar? Contact Warma UK today for a personalised consultation and take the first step towards a greener, more cost-effective future! 

See if you're eligible for free solar panel grant

See if you're eligible for free solar panel grant

Athira Harish

Athira Harish