Onsite renewable energy in commercial buildings

The energy use and carbon impact of buildings has come into sharp focus as we deal with a combination of energy price spikes and net zero goals.

This has led to a growing need to manage energy consumption more actively, and where possible onsite generation. Luckily there is an existing array of technologies which can help with these thorny issues.

What are the technologies that can help commercial buildings reach net zero goals?

Solar PV can provide onsite generation for buildings, and if well maintained, can last for 25 years. Solar installations provide a consistent source of energy generation, offsetting electricity previously consumed from the grid. Thanks to subsidies in previous years and a continually growing manufacture base for solar panels, the costs of equipment have come down consistently. As a result, the returns and paybacks for onsite renewable energy has continued to improve. There are a few options of how it can be installed:

• Rooftop solar – Best for large clear roofs e.g. warehouse, logistics, industrial units, medical centres, shopping centres, supermarkets.
• Car port solar – Car ports require large car parks e.g. out of town offices, park and ride, shopping centres.
• Ground mount solar – Using the same technology as in larger solar farms, ground mounted solar installations can be located on land adjacent to a building or site.

Alongside solar, there are complementary technologies which should be considered together to maximise the savings and carbon emission reductions:

• Energy efficiency – Efficiency measures such as lighting, controls and metering considered alongside solar can reduce demand, costs and carbon emissions.
• Heating – This includes heat pumps as well as larger heat networks which increase heating efficiency and ideally provide electrification.
• Battery storage – On a building level to date it has been challenging to get the numbers to stack up unless energy security or very ambitious carbon targets are considered.
• Electric vehicle charging – Although most electric vehicle charging will happen at home, workplace, roadside and destination charging will be needed.

What are the challenges of getting these technologies installed on listed buildings and how can these be mitigated?

Rightly, there are restrictions and additional hurdles when considering development at listed buildings or similar sites. In order to deliver renewable technologies for these buildings it is useful to consider how these can be delivered in a way which mitigates the visual impact as much as possible. For solar panels, this often includes making use of parapet walls or similar to conceal installations. For heat pumps, screens which are in keeping with the building and surroundings can be used to hide the outdoor plant which is needed. Planners generally want to encourage deployment of these technologies but need to feel that visual impact has been properly considered and a solution provided.

Does gas still have a place in heating buildings?

In order to decarbonise heating it is necessary to move away from gas boilers and assess the feasibility of heat pumps installation where possible. As the electricity grid continues to decarbonise, the emissions from electrical heating sources will reduce, as it has done to date.

There are challenges in installing and using heat pumps. For larger systems, the issues most often arise in buildings which have small electrical supplies, no space for internal equipment or have a more intermittent occupancy profile which can result in low temperatures or high costs. In some cases, gas boilers can provide top up or back up heating for heat pump systems to help reach peak temperature and manage costs in the short term.

What are the risks of battery storage systems?

Although battery systems are generally safe, there have been reports of fires resulting from battery equipment which can occur. Ensuring that the systems are installed and maintained correctly over their lifetime by an accredited and experienced installer helps to reduce this risk. Installing batteries in more remote, well-ventilated areas helps to cool the batteries and reduce the areas impacted if an electrical fault occurs.

What are the paybacks for these types of technologies? 

Paybacks naturally have a range depending on technology deployed, the system size and how complicated the project was to deliver. Lighting improvements can pay back in 3-4 years, solar PV systems can pay back in under 10 years for medium or large rooftop schemes. With other technologies like heat pumps or battery storage we would need to complete a feasibility based on the particular building to advise.

Does the weather mean that solar does not perform very well in the UK?

Solar PV performs well in the UK, generating renewable energy wherever it is installed across the country. As you would expect, panels do generate more in southern regions compared to the north. The pitch and orientation of the panels can be optimised to maximise generation, but also need to take into consideration the existing structure and orientation of the building in question. Ensuring panels are cleaned once a year, especially next to busy roads or near the coast, is important to ensure any build-up of dirt is removed to ensure generation is as estimated.

How can we address concerns about the Chinese supply chain in our procurement?

The Sheffield Hallam report into forced labour highlighted issues in the solar panel supply chain which need to be taken seriously and considered in the procurement process. There are particular manufacturers named in the report which should be avoided in the first instance.

During procurement it is important to highlight this issue to contractors through a well-designed tender, this will help to ensure that contractors engage with their supply chain to provide assurances and documentation from their supply chain wherever possible. Some contractors are aware of this issue and have already adjusted their equipment suppliers to minimise exposure to forced labour concerns.

Carter Jonas are keeping tabs on other manufacturing routes in the US and Europe who may provide future capacity with an audited supply chain.

Carter Jonas case studies 

We have acted on behalf of Yorkshire Water Services to analyse half hourly consumption data and undertake planning / grid feasibility studies across their portfolio, to identify and prioritise the development of solar PV schemes with a private wire to the treatment works. More than 50 sites have been reviewed and deemed commercially viable for development. 

Working with the Crown Estate, Carter Jonas managed the project feasibility and delivery phases of solar farm and wind project at neighbouring farms. This project was complicated by the joint venture between the tenant and the Crown Estate, which required careful problem solving to allow the project to proceed in a way that worked for both parties. We have since continued to manage the ongoing energy payments in relation to the solar and wind installations.

About Carter Jonas

Our team can provide consultancy advice relating to solar PV and these complementary technologies.  In terms of particular services, the team is experienced in providing a range of feasibility, enabling service including grid applications, tendering, project delivery and introduction / referral services depending on the client's needs.

We understand that not every company has the capital available to be able to install these systems themselves. We work with partners to provide flexible funding solutions to allow technologies to be installed so that the site owner or tenant can still benefit from a reduced energy rate.

Get in touch with one of our experts today to discuss your requirements.