Distribution centers and warehouses have always been focused on efficiency. In the past, that mostly meant investments in automation to shave seconds off order fulfillment times. Today, rising energy costs and a push for supply chain sustainability have made energy efficiency and carbon neutrality a top priority for the warehouse industry. 

According to The U.S. Energy Information Administration (EIA), the commercial sector accounted for 18% of energy use in the U.S. in 2020, making commercial buildings a prime target for efficiency improvements. In some regions, government regulation may be on the horizon for distribution centers: starting in 2022, Southern California warehouses will be required to take steps to mitigate or offset air pollution from their facilities, as well as emissions from trucks moving goods to or from their location.

What Is a Green Warehouse? 

There is no single measure of efficiency that makes a building “green.” Instead, certifying organizations like LEED (Leadership in Energy and Environmental Design) consider the entirety of a building’s design, from the energy consumption of its HVAC system to the environmental impact of its site location. Certification is awarded based on the sustainability of the building's overall design. 

According to the U.S. Green Building Council, as of May 2021 there were 1,571 LEED certified warehouses and distribution centers operating globally. Whether you strive to earn this certification or simply want some benefits of sustainable practices, here are six tips to help make your warehouse more green.

1. Aim for HVAC Efficiency

Warehouses can be energy hogs when it comes to heating and cooling. The building has a lot of surface area to radiate away heat in the winter, and thin-skinned metal walls are a poor insulator. Investments in HVAC efficiency are a win-win: they can shrink your facility’s carbon footprint and cut energy costs simultaneously.

• Invest in insulation: Preventing heat from escaping the building is one of the simplest ways to cut your warehouse’s energy consumption. According to the prefab construction broker Metal Building Price Guide, investments in insulation of metal warehouses can pay for themselves within two years.  
• Mind the gaps: Open gaps in the loading dock can be incredibly wasteful. According to Plant Engineering Magazine, leaving the hinge gap around a trailer’s swing-open style doors unsealed will create a 2.5-square-foot opening to the outside. That’s like leaving a window open all winter. Dock seals can limit the warm air that escapes the loading dock.
• Circulate stagnant air: Warm air rises, so it’s common for a multi-story warehouse to be chilly at ground level, where most of the workers are, and broiling on the unoccupied mezzanine level. Don’t allow warm air to collect at your warehouse’s roof. High-volume low-speed fans can get the stagnant layer of warm air moving, pushing it back to ground level where it’s needed. In the summertime, Plant Engineering reports that these fans can create a light breeze that will reduce the building’s heat index by as much as 11 degrees, creating up to 30% savings year-round in HVAC costs.
• Automate thermostats: Programmable climate controls can make your HVAC system more efficient by turning down the thermostat at night or on weekends when the facility is empty. A smart HVAC system that divides the warehouse into zones can minimize heating and cooling in unoccupied spaces while maintaining comfortable temperatures where workers are present.
• Electrify the heat: Finally, a good way to cut your facility’s carbon footprint is to stop burning natural gas for heat. In all but the coldest environments, heat pumps are typically more efficient than gas furnaces. According to energy consultants Schneider Electric, a heat pump will reduce your building’s carbon footprint in many climates, even if 100% of the electricity powering the system comes from a natural gas fired plant. 

Electric heat comes with some drawbacks: heat pumps are expensive, and they are not efficient in extremely cold climates. If converting the entire warehouse to heat pumps is prohibitive, consider installing ductless mini-split units to heat smaller areas like break rooms and offices, which you may want to keep warmer than the rest of the warehouse.  

2. Look at Your Lights

 A study in the journal Energies found that lighting is the second biggest category of energy consumption in warehouses in most cases, after heating and cooling. Investments in lighting efficiency can make your facility more sustainable.

• Replace old lighting technology: Replacing incandescent and fluorescent lighting fixtures with high efficiency LEDs or metal halide bulbs is a straightforward way to cut energy consumption. According to Energy Star, LEDs are 90% more efficient than incandescent bulbs and, unlike fluorescent lights, they produce virtually no wasted heat.  
• Add automatic controls: Another advantage of LEDs is their near-zero warmup time, which makes them suitable for use with occupancy sensors that can turn the lights off when workers are not present.   
• Aim light where it’s needed: Warehouses can also cut lighting bills by optimizing their bay lighting fixtures. Make sure your lights are illuminating the ground level of aisles, and not scattering light across the tops of storage racks. 

3. Electrify Handling Equipment

Propane- and LPG-fueled forklifts expand your facility’s carbon footprint twice: not only do they emit carbon pollution, but their exhaust fumes must also be vented and exchanged with cold outdoor air, adding to your HVAC costs. The American Conference of Governmental Industrial Hygienists recommends an additional 5,000 cubic feet per minute (CFM) of fresh air circulation for every 60 horsepower LPG or propane forklift operating inside the building. That’s a lot of air to heat in the wintertime. 

Switching to electric forklifts can directly reduce your facility’s emissions. According to Manufacturing.net magazine, switching to an electric forklift directly eliminates over 120,000 pounds of carbon dioxide pollution for every 10,000 hours of use. Electric forklifts also offer lower lifetime operational and maintenance costs, creating potential long-term cost savings. 

4. Turn Off Idling Trucks

The EPA reports that a truck idling at a loading dock burns a gallon of diesel every hour, releasing plant-warming carbon dioxide, smog-creating sulfur dioxide and fine soot particles that can cause lung and heart damage among loading dock workers.

Instituting a “no-idle” policy can help eliminate these unnecessary emissions. Idle Free California recommends that companies institute formal policies and practices that guide driver behavior to reduce idling. They also recommend requiring trucking contractors to equip vehicles with auxiliary power units and fuel-operated heaters, which reduce the need for idling. 

5. Install Green, Reflective or Photovoltaic Roofing

A bare warehouse roof is a missed opportunity for energy efficiency. Alternative roofing materials can make your roof a platform for renewable energy and carbon absorption.

• Skylights: Translucent skylight panels can admit natural sunlight, cutting your lighting costs. 
• Solar panels: Rooftop solar panels generate green electricity. According to Commercial Construction and Renovation, rooftop solar is a great investment that can really help lower operating costs for commercial properties, In most cases, the initial investment pays for itself between 3 and 7 years of using the panels. 
• Cool roofing: Reflective “cool roof” material reflects solar heat away from the facility. The Department of Energy reports that reflective roofing materials can lower the roof temperature by 50 degrees or more during intense sunlight, cutting down on cooling costs. 
• Green roofs: Covering the building with a green roof can yield sustainability benefits. According to the nonprofit Green Roofs for Healthy Cities, covering your building’s roof with plants can reduce cooling costs by 75% in temperate climates and absorb as much as 90% of summertime stormwater runoff.

6. Look Into Landscaping

The grounds around your warehouse can be designed for sustainability. A sea of asphalt is inherently inefficient: it absorbs heat in the summer, creating a “heat island” effect that can raise the ambient air temperature, according to the Lawrence Berkeley National Laboratory. Planting trees in unused spaces will help absorb heat and cast shade on hot days. 

Get more tips and insight on sustainable practices for your facility.