If your business operates across multiple sites, solar can look like a straightforward opportunity. You have several buildings, multiple electricity bills and plenty of unused roof space. Surely the answer is to put solar panels on as many sites as possible? If we’re honest, it is rarely that simple.
When we talk to businesses about multi site solar, one of the first questions we hear is: “Which site should we start with?”
For businesses with offices, warehouses, retail locations, manufacturing facilities, care homes, agricultural buildings or other commercial properties across the country, the best starting point is not necessarily the biggest building or the site with the largest electricity bill. It’s best to review how each site uses energy, what the building can support and how solar fits into the wider energy strategy. So, if you are considering solar across multiple business premises, where should you begin?
Start with your energy use, not your roof
It is tempting to start by looking at satellite images and identifying which buildings have the largest roofs and while roof space matters, it is only one part of the picture. The first step in a multi site solar strategy should be understanding how each location uses electricity.
For example, a site operating seven days a week with refrigeration, machinery, lighting or other continuous loads will have a very different solar opportunity from an office that is largely empty at weekends. This matters because solar generation is greatest during daylight hours. The more electricity your business can use while the panels are generating, the more value you get from the system.
For each site to understand the best place to start, you’ll want to review:
- Annual electricity consumption
- Half-hourly or interval energy data, where available
- Operating hours
- Seasonal changes in demand
- Current electricity costs
- Existing or planned equipment
- Available roof or ground-mounted space
- Any restrictions on the building or site
- Future plans for the property
Look for the sites with the strongest solar opportunity
Once you understand how each site consumes energy, you can start comparing the potential for solar. A strong candidate will have high daytime electricity consumption, a suitable roof and a long-term plan to remain in the building. For example, imagine a business has ten locations; one site has a huge warehouse roof but relatively low daytime electricity consumption and another has a smaller roof but operates energy-intensive equipment throughout the day. The second site will provide a more attractive starting point because a greater proportion of the electricity generated could be used. This is one of the reasons a portfolio-wide approach is so important.
With multi site solar, you are not just asking, “How many panels can we fit?” You are asking, “Where can solar make the biggest difference to our energy use?” That difference can change how a project is prioritised. We are on hand to help you understand all of the nuances of your energy use to ensure the deployment is strategic and helps you yield the best savings from the very beginning.
Your biggest electricity bill is not automatically your best site
High energy consumption needs to be considered but it should not be used as the only measure. A site with a very large electricity bill may also have high demand outside solar generation hours. If much of its electricity is consumed overnight, for example, the economics of solar will look different. Equally, a site with a smaller annual consumption could have an excellent daytime load profile and a well-positioned roof.
Don’t overlook the building itself
Before committing to a solar installation, the building and roof condition also needs to be assessed. Commercial and industrial buildings can vary considerably in age, construction and condition – so a large roof does not necessarily mean it is ready for solar panels. The condition and construction of the roof, its orientation and shading, access for installation and the available electrical infrastructure all need to be assessed before a design is generated.
For older buildings, roof condition is particularly important. If a roof is likely to need significant work in the near future, it will need to be addressed before installing a solar PV system. There is an option to install solar at the same time as roof improvements with retrofit services, which can make the cost of both elements more competitive.
There will also be planning considerations, structural requirements and any electrical constraints to investigate. This is another reason why a site assessment across all sites should come before deciding where to invest first.
Consider what is happening at each site in the future
A solar system is a long-term investment and can have a lifecycle of around 30 years, so your business plans over this time matter. Perhaps one warehouse is due to expand. Maybe another site is being considered for relocation. You could also be planning to introduce electric vehicle charging, heat pumps, refrigeration or additional production equipment. These changes will naturally affect electricity demand considerably.
A multi site solar strategy should therefore consider not only what each building consumes today, but what it is likely to consume in the years ahead. There is little value in designing a system around today’s electricity use if you already know that the site is going to change significantly next year.
Think about battery storage separately
Solar and battery storage are often discussed together, but they solve different problems. Solar generates electricity during daylight hours. Battery storage can provide additional flexibility by storing electricity for use later. For some sites, solar alone may be the appropriate starting point. For others, a battery could form an important part of the wider strategy that makes a significant difference. As above, this also depends heavily on how the site operates.
If a business generates more solar electricity than it can use, battery storage will help shift some of that energy to a later period. There are also other potential considerations around electricity tariffs, demand and how the site interacts with the wider electricity network. The important point is not to assume that every site needs the same solution and no matter how many sites you have, we will always take a bepsoke approach to each site.
Start with a portfolio assessment
For businesses with multiple premises, we believe the first step is a portfolio assessment rather than immediately commissioning ten separate solar projects. This allows you to put your sites side by side.
You can identify which locations have:
- The strongest solar potential
- The highest daytime electricity demand
- Suitable roof space
- Fewer technical constraints
- Strong potential for future energy demand
- Opportunities for battery storage
- The clearest route towards reducing grid electricity use
From there, you can create a sensible rollout plan. Perhaps three sites are suitable for immediate development, while several others need further investigation. Another site might be better suited to solar after planned building works. That is never a problem and it is exactly why portfolio planning is essential.
A phased approach can make sense
For many businesses, installing solar across every location simultaneously is practible. A phased approach can allow you to start with the sites where the opportunity is clearest, learn from those projects and then apply that knowledge to the rest of the portfolio. This also supports internal planning.
Managing a solar project across multiple locations involves stakeholders, budgets to approve, operational considerations to manage and potentially different requirements at each property. Starting with a defined group of priority sites can make the process more manageable. It also allows your business to build a longer-term energy plan rather than treating each solar installation as an isolated project.
Don’t forget grid connection requirements
Electrical infrastructure is another important consideration for multi site solar. The amount of solar you can install at a particular site isn’t determined solely by roof size. The existing electrical infrastructure and local network capacity will also influence what is possible. Therefore, we’ll review grid connection requirements early in the process. This is particularly important for larger commercial solar projects, where connection requirements can become more complex. Understanding these considerations early on will help avoid surprises later too!
So, where should your business start?
If your business operates across multiple locations, there is no universal answer to which site should come first. The right starting point is the site, or group of sites, where solar makes the most sense when you consider the whole picture. That means looking at energy consumption, daytime demand, roof suitability, building condition, operational requirements, future plans, electrical infrastructure and the potential role of battery storage.
Most importantly, look at your properties as a portfolio. Multi site solar does not need to mean installing identical systems on every building. The smarter approach is to create a strategy that recognises the differences between your sites and build a solution based on their individual energy use, roof space and condition. Start with the strongest opportunities and have a rollout plan so you can benefit from solar across your portfolio in both a timely and sensible timeframe.
Take the first step with your site portfolio
If you are considering solar across multiple business premises, you do not need to have the entire plan worked out before starting a conversation. At Harvest Green Developments, we believe the best conversations begin with understanding your business, your buildings and how you currently use energy. From there, we can help identify where solar could fit within your wider energy strategy and which sites may be worth investigating first.
Because the question is not simply “Can we put solar on our buildings?” It is “Where can solar deliver the most meaningful value for our business, and how do we build from there?” For a business with multiple locations, that is where a good multi site solar strategy begins.
