So you’ve decided that you want to install a solar panel system in your home and now you’re wondering just how many panels you need. There isn’t one answer to this question as each household will have different requirements, different budgets and a different amount of space to work with.
The first question to ask yourself is what your goals are.
Do you want your solar panels to provide all of your energy needs or just to provide a proportion of it?
Are you looking to reduce your carbon footprint and go completely off grid?
Are you hoping to make a return on your investment by reducing your energy bills and selling your excess energy back to the National Grid?
If you are looking to go completely off grid you will need a much larger system than someone who’s only goal is to simply reduce their energy bills.
Once you have decided on what your end goals are it is best to consult with a professional solar installer who would be able to come to your home and perform a full solar evaluation.
The size of your household will also be a key factor. A family of three would need a much smaller system, such as a 3kw system, than a family of six who would require at least a 6kw solar installation.
What’s your daily energy usage?
Working out your daily energy usage is a great place to start. By taking the monthly usage in kwh from one of your current energy bills you will be able to divide this by 30 days and work out your average daily requirements. This will help you decide on a suitable sized system.
A 3kw installation using 250W panels would need 12 panels.
A 6kw installation using 250W panels would need 24 panels.
There are many different brands of solar panels but the average size of one panel is around 1.6 square metres.
How many hours of daylight will you have to generate energy?
Where you live in the country and the amount of daylight hours can also affect the size of the system you require. The South of the country typically receives more sunlight and daylight than the north of the country so would need a smaller system.
Remember solar panels do not work at their maximum capabilities at all times.
The seasons and weather plays a massive part in how much energy they can collect and convert.
Your solar system will still work in the winter but it will generate a lesser amount than in the heat of the Summer so you may want to go for a larger system to offset this.
How much roof space do you have?
Another factor to consider is how much roof space you have for your solar panels. Using our average panel size above, a 3kw installation would need roughly 19.2 square metres of roof space and 38.4 square metres for a 6kw installation.
If you do not have the roof space you can install solar panels at ground level, these would work best when facing a south west or south easterly direction at an angle of 20-50 degrees. Ground level solar panels not facing this direction will collect and convert considerably less energy.
Once you have decided on what your end goals are it is best to consult with a professional solar installer who would be able to come to your home and perform a full solar evaluation. They will be able to help you decide on what size system would suit your needs and your budget.