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Calculating the Number of Solar Panels Needed for Your Business Premises

The most accurate answer to “how many solar panels does my business need?” is probably “how long is a piece of string?” That is to say, the answer really does depend on a range of factors! No two businesses are identical in their energy needs, and each will use energy in a different way.

Exact answers are not easy to come by, simply because a detailed and thorough consultation with a commercial solar panel expert is the only way to understand which solar panel system will work best for you. With solar power, there is no one-size-fits-all. Nevertheless, in this guide, we’ll look at factors to consider when estimating the number of panels required.

The factors influencing the number of panels needed

Many business owners immediately think of the size of their business premises, but this isn’t the only thing to bear in mind. There are four main factors influencing solar panel number:

  • The size of the roof (or area where panels can be installed)
  • The size of each panel
  • Your electricity consumption size

 The profile of your consumption e.g. 9 to 5 or 24/7/365. Other things like your business niche and nature of the premises certainly matter, but to a lesser degree than the above. Cost is also a significant factor, and determines to a large extent the type of panel you’re willing to invest in. This in turn influences the size and type of the panel, since more expensive, more efficient panels are typically smaller.

What it ultimately comes down to is how much energy your business requires, and how best to supply this given the parameters and limitations in place. To assess the impact of each of these factors, you’ll need to conduct a detailed professional assessment, which takes into account both your energy profile and your business premises.

Start with how much energy you are already using

According to solar power experts Mypower, solar energy is around 60% cheaper than grid-supplied, so it’s more than worth it for any business. It’s tempting to imagine that all you have to do is try and squeeze as many panels as possible onto the roof you have, but it’s a lot more complicated than that. A good place to begin is to appraise your current energy usage. Try to understand exactly how much energy you use (monthly and over a 12 month period) as well as the times of day where your demand is heaviest. Your electricity bills can provide plenty of useful data. For those with solar panels already installed, Mypower offers a solar PV monitoring system which provides a holistic view of how solar PV is benefitting your business.

Calculate how much energy you could generate

Naturally, the other part of the equation is to determine how much energy your premises is capable of generating via solar panels. This is where expert advice is non-negotiable. How much energy each panel generates depends on its size, the kind of panel it is, where exactly it has been installed (i.e. the angle, pitch and elevation), the region of the country and daylight hours received, panel age and how well the solar array has been installed.

A smaller, more efficient panel can generate more energy than a larger, less efficient one, but  can be more expensive. On the other hand, a better quality panel installed incorrectly and in a poor location may perform worse than a cheaper panel that is in the optimal location. Finally, many business owners are not aware of the option to only partially supply their electricity needs with solar – i.e. even a small solar PV system can offset energy costs. Sitting down to carefully juggle all these variables takes time and sometimes, compromise.

Choose the panels that work for you and your business

There is no “best” type of solar panel – what works well for one company will not work as well for another. Solar panels come in all shapes, sizes, types and price points. Panels usually have outputs ranging from 270 to 410 watts, and are predominantly either monocrystalline or polycrystalline (the former usually more expensive but more efficient).

For businesses with only limited roof space, solar PV installers usually recommend a smaller number of high-output panels. It’s also possible for those businesses with bigger roof areas to install more panels than they need, if they want to capture and store excess energy in batteries to later sell back to the national grid.

The number of panels your unique business will need depends on a number of factors, not least of which is your budget! Solar panels are environmentally friendly, incredibly long-wearing and promise to help you make enormous savings in the long term. But it’s worth taking the time to understand the very best solar PV system for you, so you can ensure you’re getting the most from your panels from day one.

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