How many solar panels does my business need?
How many solar panels does my business need?
29th October 2019

It’s a question our experts often get asked here at the Low Carbon Energy company, and to be honest the answer varies, depending on a couple of different factors which are specific to your business. While you’ll probably find it difficult to get any exact answers without a detailed consultation with an expert, it can be helpful to familiarise yourself with these factors in advance. This way, you can have at least a rough idea of what’s involved by the time you’re ready to start the installation of your commercial solar panel system in earnest. We’ll explore the biggest ones below!

The 4 biggest key factors

You don’t need specialist knowledge to guess that the size of your premises is one of the biggest determining factors in our process, but it’s certainly not the only one. In almost all cases, the number of solar panels your commercial solar panel system needs will depend on the following factors:

  • The electricity consumption within your premises
  • The local yield (i.e. daylight hours)
  • The size of your roof
  • The size of the panels

In many ways, your industry and the nature of your business can make a difference too, but only to the extent that it influences the construction and requirements of your premises. For example, a law firm will often naturally be less energy-intensive than a manufacturing or industrial facility, so in most cases it will need fewer solar panels.

It’s not a hard and fast rule though – hypothetically, a reasonably small manufacturing facility might need fewer panels than an exceptionally large law firm. It’s just a part of why we’ll always base our key decisions first and foremost on the buildings and environment, rather than solely the nature of the business.

Our process for determining solar panels

When you approach us for our services here at Low Carbon Energy, we’ll always start by conducting a detailed assessment of your premises and energy profile, so that we can supply and install the best possible system that works for you. Here’s a broad overview of our process.


1. Analyse electricity consumption

Contrary to what some people first assume, designing an effective solar solution isn’t just a case of filling every available space on the roof. The best solar panel system isn’t the one that’s largest – it’s the one that’s most efficient.

At Low Carbon Energy, we’ll review your existing energy consumption via electricity bills, half-hour data or any other consumption data that you might be able to provide. We’ll use this to review your ‘load profile’ – basically, how and when you use the electricity. This enables us to design a system that best suits the specific requirements of your business, giving you the best returns on investment.

2. Calculate the level of electricity generated

Solar energy is generated from daylight rather than sunlight. So if you’ve ever asked: do solar panels still work on cloudy days, the short answer is very much yes! (We’ve explained the full details why in the linked article.)

When we make our calculations, we use dedicated software which accounts for 20 years of geographical data, and we also consider the location, pitch and elevation of the roof, and the array layout. All this data ultimately gives us a very accurate estimation of what we can expect to be generated, which we use as a starting point to determine the basis of your solar PV system.

3. Finalise the type of solar panel being used

Solar panels obviously come in a wide variety of sizes and outputs, and like most other providers, we don’t use a one-size fits all. Instead, the exact size of the panel used is always determined by the customer’s specific requirements. Panel sizes can vary from anywhere between 270 watts to 410 watts, and typically the larger the wattage/output, the more expensive the panel.

Once we have all the required information to hand, we’re then in the perfect position to select the size of panel that best suits your system. For example, if your business has limited roof space but a large energy consumption, the best option would often be to select a large output/wattage panel. This enables us to maximise the available roof space, effectively meeting the energy demands within your premises.

How much do commercial solar panels cost?

This is another of the biggest questions! Just like the number of solar panels though, it’s difficult to give a definitive answer without a proper consultation, since the final figure depends so much on the specifics of your business and premises. We’ve done an entire post on this, but essentially many of the same factors apply – it all comes down to how much energy you’ll consume, and the necessary capabilities your solar PV system will need to offset this.

money for solar

As well as the actual installation, the cost of solar panels also encompasses all the design, project management, administration and other costs. We lay all of these out for you during the consultation, so when you get a price for your system, you can be sure there’ll be no sudden surprises further on down the line!

What’s more, we offer all the specialist expertise, equipment and labour in-house right here at Low Carbon Energy, and for decades we’ve been using these to deliver solar PV systems for customers across a range of sectors. With over 30 years of combined experience, you can count on us to be able to create you a system that’s tailored specifically for your premises, providing maximum efficiency and return on investment. Feel free to give us a call today on 01282 421 489 to see how we can help you take the first step towards cheap, green, unlimited energy.

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