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Top 5 Energy Efficiency Tips for Repurposing Buildings

Written by Michael Tobias | 4/29/21 2:00 PM

Many commercial buildings are being repurposed to offer high demand services, which include warehousing and data center infrastructure. In the case of hotels and offices, repurposing into apartments is also a viable option. In all these projects, building owners have an excellent opportunity to improve energy efficiency.

Each property is unique, and an energy efficiency measure that works for a nearby building may be ineffective for you. However, there are energy efficiency measures that work in most commercial buildings, and they are recommended very frequently by energy consultants.

A building repurposing project is an opportunity to improve energy efficiency. Get in touch for professional energy modeling services.

In this article, we will discuss 5 energy efficiency measures that are recommended by experts when repurposing a building. By implementing them, you can reduce power and gas bills permanently, while lowering the environmental footprint of your building.

1) Upgrading to LED Lighting

LED lighting is one of the most popular energy efficiency measures for buildings, and there are many reasons for this. LEDs normally save 30-50% when replacing fluorescent bulbs, they save over 60% when replacing HID bulbs, and savings exceed 80% when replacing halogen or incandescent lights.

In addition to being more efficient than older lamp types, LEDs have simple maintenance needs and a long service life. While an HID bulb is normally replaced in under 10,000 hours, and most fluorescent bulbs last less than 20,000 hours, a service life of 50,000 hours is typical for equivalent LED lamps.

Upgrading to LED lighting is also a relatively simple project. Since LEDs consume less power than the lamps replaced, the existing wiring will have more than enough capacity for them. Unless the wiring or its insulation have been damaged, there is no need to replace circuits. There are also LED retrofit kits that can be used with existing fixtures, replacing only lamps and internal connections.

2) Upgrading to NEMA Premium Motors

Electric motors have many applications in buildings, and they are used by equipment and appliances of all sizes. In a large commercial building, the motors that drive ventilation systems and water pumps can have a very high energy consumption.

  • A simple way to reduce ventilation and pumping costs is by upgrading to NEMA Premium efficiency motors.
  • They can be selected with the same physical dimensions as the motors they replace, ensuring they are compatible with the existing bases and equipment. 

The exact savings achieved by a NEMA Premium motor depend on the application and operating schedules. However, a large facility can save thousands of dollars per month when all motors are upgraded.

3) Upgrading Insulation and Improving Airtightness

Many buildings have high electricity and gas bills due to a hidden form of energy waste: uncontrolled heat movement through the building envelope. This takes the form of heat gain during summer, and heat loss during winter.

  • Heat gain and heat loss waste energy because they force HVAC systems to work harder. 
  • Air conditioners must provide additional cooling to compensate for the extra heat gained during summer, and space heating systems are equally affected by heat loss during winter.

An efficient building envelope has good insulation and airtightness. Heat movement across walls and other elements exposed to the exterior is minimized, while air movement is fully controlled by ventilation systems and openable windows.

4) Upgrading Air Conditioning Equipment

In many commercial buildings, air conditioning is by far the highest energy expense during summer. The operating cost can be especially high with warm and humid weather, since the AC system must also remove large amounts of air humidity. A building repurposing project provides an excellent chance to replace air conditioning equipment.

  • The exact savings of an AC replacement will depend on the building schedule and external factors like the weather, but savings of over 30% are commonly achieved.
  • When replacing very old AC units, even savings of over 70% are possible.

Keep in mind that you may need to change the air conditioning system layout. For example, if an office building with a central AC system is converted into an apartment building, you will need an independent AC system for each dwelling.

5) Upgrading Space Heating Equipment

Just like air conditioning is the top energy expense in summer, space heating can have a high cost during winter, especially in places with very cold weather. An adaptive reuse project also gives an excellent opportunity to upgrade heating equipment, a procedure that would be disruptive when the building is operating normally.

A building owner can decide to go 100% electric with an efficient heat pump system, which eliminates the need to burn heating fuels onsite. If the building continues to use combustion heating, a natural gas boiler with a high Annual Fuel Utilization Efficiency (AFUE) offers the lowest operating cost and environmental impact.

Conclusion

When an adaptive reuse project changes the purpose of a building, owners also have the opportunity to reduce energy bills. Many upgrades that would be disruptive when there are tenants can be completed without bothering anyone. Energy efficiency is also a selling point when a repurposed building has tenant spaces for rent. If two buildings are similar but one of them has a superior energy efficiency, the benefit of paying lower energy bills will attract tenants.