MEP CA AB 1103

Reduction of Energy Use in Commercial Buildings

A building is not a thing, but a set of systems. As with any system, it can be difficult for observers to identify how each facet impacts the whole. A building owner or manager looking to reduce their energy footprint may have a tough time identifying where their electricity, natural gas, and other fuel sources are going, particularly in a building with no sub-meters. What follows is a general look into how commercial buildings operate in the United States, geared toward helping Property Owners, Managers, and occupants understand how their decisions and habits affect the overall energy footprint.

The most crucial time period for a building in terms of its energy efficiency is the design phase. With a pre-existing building you already have a set threshold of how well your building can perform given the technology and infrastructure it was constructed with. This does not, however, mean that you are unable to create positive change. There are a number of measures you can put in place and alterations that can be made to building operation to significantly decrease its energy footprint.


The most important step in improving your building's performance is tracking its present energy consumption. You cannot optimize what you are not measuring. If you are not measuring you are not optimizing.Benchmarking and ENERGY STAR are a fantastic way to track utility use for your building as a whole. According to the EPA, buildings that earn an ENERGY STAR award use about 35% less energy than other buildings of a similar type. Sub-metering your building will give you a more precise look into where energy usage is going within the envelope of your building. This can uncover problem spaces within the building (either energy intensive tenants or inefficient/defective equipment) and allow you to target the areas that need it most. If these measures are still insufficient to identify where and why you are using too much energy, an Energy Audit is a great option.


Alterations to a building's standard operations have the potential to drastically decrease a building's energy consumption. Installing an Energy Management System or Building Management System can be expensive, but it will allow your engineer to keep better tabs on the building's infrastructure and even remotely shut down equipment that is running unnecessarily.

There are also plenty of simple and inexpensive measures one can take to reduce energy use. Keep your ventilation system unobstructed by stacks of paper, filing cabinets, and other office supplies to reduce the amount of energy it takes to pump air by up to 25%. Considering that HVAC systems account for approximately 52% of energy use in commercial buildings nationally, small steps can provide much-needed reduction. Adjusting thermostats can also have a significant impact, in extreme cases reducing energy consumption by up to 50%.


Lighting is another area where one can reduce excess energy usage with minimal effort. According to a recent survey light levels in 50-60% of work places are higher than necessary. Turn off lights when they are not required or when natural light is sufficient, and you can cut between 10-40% of your lighting expenses. Implement a regularly scheduled lighting maintenance program to make sure your lighting efficiency is up to date. High efficiency lighting systems can save as much as 50% of your lighting costs. You can also install occupancy sensors to ensure lights do not stay on when they are not needed.


Often times the energy usage from office equipment is dictated by the whims of occupants. This means information and education are key to combating unnecessary energy expenditure on equipment that is not in use. Setting computers to go into sleep mode after 5 to 20 minutes of inactivity can save $20-$75 per year, per computer. In a large office building those savings can rack up fairly quickly. Also, make sure your tenants are unplugging electronics like cell phones and laptops once they have been fully charged. Adapters and cords plugged into outlets draw energy even if they are not charging.

An additional step that can be taken is to perform a nighttime equipment audit. Have someone inspect the building after hours to see what equipment is unnecessarily left on all night. Then you can make sure that those who close down the building are aware that these items are being left on so that they can add shutting them down to their office closing routine.

In conclusion, cooperation, conversation, and education are key to reducing commercial building energy consumption. Make sure your tenants, building operators, and other staff, are aware of the part they can play and encourage them to work as a team to make necessary changes.

Contact MEP today for questions about Sustainable Commercial Building Engineering Design, ASHRAE Level I & II Energy Audits, ENERGY STAR, AB-802 Benchmarking and LEED at 310-782-1410.