GUEST COMMENT The five steps to boosting energy efficiency in warehousing

UK warehousing is one of the fastest-growing sectors in the economy. Between 2015 and 2021, the number of warehousing units increased by 32%, and there was a significant growth in larger units of over 90,000 m2, driven by the move to online retailing. High-street stores and supermarkets are also expanding online offerings, while digital-only sellers are booming. As a result, the ecommerce sector expanded warehouse occupancy by 614% over the six-year period.

With this growth there must be greater efforts to reduce carbon impact, writes James Harman, business development manager for corporate sales at Mitsubishi Electric.

In fact, data from the British Retail Consortium shows that the retail sector is responsible for approximately 215 megatons of CO2 emissions every year in the UK, making it the sector that contributes the most to greenhouse gas emissions.

The size, design and operation of warehouses has also meant it can be challenging to make them more efficient, but new warehouses are increasingly being designed with energy efficiency in mind, and retrofitting existing warehouses should also be a priority.

To achieve a low-carbon warehouse – regardless of its size or type – facilities teams can follow these five key steps to boost energy efficiency:

Step 1: Auditing buildings and HVAC equipment to establish a baseline
Knowing where a retail warehouse is starting from is crucial when putting in place an energy reduction strategy. Billing information will provide the annual consumption of electricity and gas in the building, establishing a baseline to start tracking savings. Large warehouse operators that have a regular programme of service and maintenance should ensure checks on the warehouse heating, ventilating, and air conditioning (HVAC) equipment are included.

For smaller retail facilities, it is equally important to check on this equipment to confirm that HVAC systems are running effectively, as inefficient operation can lead to higher energy use. For example, if the air conditioning system has had to be repaired repeatedly, or if temperatures are fluctuating, it may need to be overhauled or even replaced. Wear and tear on the equipment is one of the earliest signs that heating and cooling systems are malfunctioning around the warehouse.

Additionally, businesses often change working or occupancy patterns, meaning that spaces are used differently. It is crucial to check that the timings for heating and cooling equipment reflect the schedule accurately to avoid operating them when they’re not needed.

Auditing equipment is not simply about performance and functionality; it is about ensuring we have the correct information on what is in the warehouse. It is easy for information on equipment to be lost over time. Understanding exactly what models of cooling or heating technology are used, how old they are, and when they were checked for the last time will be very valuable in establishing a new and more energy efficient programme.

Step 2: Setting a specific target for energy efficiency
Many new warehouse developments are adopting BREEAM certification to demonstrate sustainability credentials. The BREEAM scheme is helpful to building owners and designers because it provides clear guidance on design requirements to achieve a rating of ‘Good’ or ‘Excellent’.

However, for existing buildings, finding a benchmark to aim for is currently more challenging. For example, no ‘Net Zero’ schemes are presently designed specifically for warehouses. The lack of targets for warehousing is a real obstacle in the retail sector’s transition to net zero.

One place to establish an energy performance target with an existing building may be its Energy Performance Certificate (EPC). Commercial buildings are required to have an EPC rating, and this requirement can significantly impact a warehouse’s leasing value. Without this rating, a building cannot be sold or leased. So, we could use EPC ratings to set an initial target for energy efficiency.

The law currently sets a minimum EPC rating of E, but this is expected to rise to a C rating by 2027, and a B rating by 2030. Research shows that 78% of industrial and logistics properties have a rating of C or D.

Step 3: Prioritising investment into improvements
A further benefit of using the building EPC as the basis for energy efficiency targets is that the assessment includes recommended improvements. The recommendations are listed as ‘High’, ‘Medium’ or ‘Low’ impact, which can help identify the most impactful steps.

The changing requirements for EPC ratings are a strong argument for improvements to achieve the new minimum standards in retail. It’s also important to note that rising energy costs will reduce the payback periods for investments in efficiency. This highlights the importance of tracking energy use ‘before’ and ‘after’ improvements. Energy cost savings can be invested in further improvements or technology to maintain energy efficiency, such as building controls.

Another example of such improvements is the move to heat pumps to provide simultaneous energy efficient cooling and heating to warehouses of all sizes. Heat pumps can also be used to provide renewable hot water.

Ventilation is also another area to look at as mechanical ventilation with heat recovery (MVHR) can help reduce energy consumption. MVHR extracts stale air from a building – which would otherwise we be lost to the atmosphere – and supplies filtered air to the space. By reusing recovered heat, significant energy is saved in the system.

Step 4: Getting employees engaged in finding energy savings
Making energy efficiency part of the retail business strategy is an excellent way to achieve better outcomes. Businesses that engage staff at all levels of the organisation to raise awareness of the importance of the energy-saving objective can reach their target faster. For example, building an ‘Energy Efficiency Team’ of staff from across the business can help drive change and improvements. Asking staff for energy-saving ideas around the business allows for the identification of areas that might otherwise be missed.

Good practice should become a part of everyday working operations. For example, encouraging employees to turn off lights, heating and cooling in empty offices is simple but effective to avoid having equipment operating when not required and improve energy efficiency. It is also important to discourage wasteful behaviours such as leaving computers on overnight or using portable heaters, which consume significant amounts of energy. The Energy Saving Trust recommends using internal business communications to inform staff about why saving energy and reducing carbon is important.

Step 5: Focusing on maintenance and monitoring to save energy in the long term
Service and maintenance are critical to managing the carbon footprint and energy use of a warehouse in the long term. Engaging with the in-house or external maintenance team will help them understand the goals and ensure that they incorporate energy-focused servicing as part of their work.

Simple maintenance checks on filters in vents or air conditioning outlets can reduce the pressure on fans, which are significant energy users. Checking external air conditioning units every month to ensure the area around them is clear of leaves and other debris will retain good airflow, which is better for energy use and indoor air quality within the warehouse.

Retail businesses, small and large, should monitor energy use closely. Looking at energy bills can help identify unusual patterns of energy consumption that can then be addressed to cut waste.

Warehouses and logistics centres are some of the most vital parts of the UK economy today – supporting retailers and online sellers with fast, efficient delivery to their customers. There is growing pressure on warehouse owners and managers to meet higher targets for energy efficiency. Recent energy price rises increase the incentive to reduce energy waste wherever possible. The sector also has much potential to adopt renewable and low-carbon technologies. As the retail supply chain looks to reduce its carbon footprint, warehouses will have to play their part.

James Harman, business development manager for corporate sales at Mitsubishi Electric

Read more in the DeliveryX Warehousing Report 2023, as well as examining the sizable opportunity in warehouses to start retailer’s sustainability journey, the wider report also looks at labour shortages across the sector and the roll out of technology in warehouses.