3 Tips To Optimize Building Operations For Winter Weather December 1, 2015 | Kelia Cowan

Insights from Lee Dunfee, Cushman & Wakefield’s Senior Vice President of East Engineering Operations.
 
Welcome to December! Although winter technically doesn’t start for a few weeks, winter weather has already started. With mornings and nights dipping into the 30s – or well below that, if you’re in Chicago – it’s time to optimize building operations for the best efficiency.

Adjusting operations for the winter months is important for two reasons:

 

1. Excessive electric, water, and gas waste can be easily avoided.
2. A few key areas of building operations are often overlooked.

 

Here are 3 features to help you keep your buildings operating smoothly and at maximum performance.

 

1. Drop The Thermostat – Nighttime Setbacks

Lee Dunfee, Cushman & Wakefield’s Senior VP of East Engineering Operations, said that less than half of building operators he has spoken with understand how their nighttime setbacks function. Dunfee emphasized that this is one of the most important tools going into the winter months.
First, you need to know how long your building takes to recover in the morning. This is a bit different for every building, depending on system type, age, and use. Consider how long both the air and the items in each space – desks, chairs, filing cabinets, and appliances – will take to reach the desired temperature.

When the building is unoccupied, set the thermostat about 8-10 degrees lower than the occupied temperature. If using more advanced strategies with occupancy sensors, you may consider three different settings:

1. Set the occupied temperature to 72 degrees Fahrenheit,
2. The unoccupied setting, based on information from the sensors, at 69 degrees Fahrenheit,
3. And set a nighttime temperature at 64 degrees Fahrenheit.
Before you touch that thermostat dial, develop your building’s nighttime setback strategy at the beginning of the winter to better prepare for colder times. Be sure to consider:

1. What is the sequence-of-operation for your nighttime setback?

2. Has your team tested the function of the nighttime setback to confirm it is operating properly?

3. Is your nighttime setback temperature suitable for a proper building recovery?

There is an important balance to “strike” with nighttime setbacks with heavy consideration on efficiency, occupant comfort, and freeze protection.

 

2. Protect Your Pipes – Freeze Protection Steps

The winter months demand a delicate balance between cutting energy costs and avoiding frozen pipes, which would be a much bigger and more expensive problem. With a well-planned energy reduction strategy, building operators can drop their consumption while incorporating freeze protection.

In the image below, you can see a chart of a building’s kW consumption (green line) over the course of a week last January. If you look by the arrows over Monday and Tuesday, you will notice the building’s energy consumption did not return to baseload (in this example, about 250-300 kW) on Monday night. Why?

Well, if you look at the temperature (blue dotted line), you’ll see that it was actually expected to drop from 40 degrees on Monday to 3 degrees on Tuesday!

 

WinterBuildingSchedule

Many building engineers will decide to run buildings at night before a cold day, especially when it’s the first shock of the season. However, this decision must be made on a case-by-case basis.

Dunfee explains, “Some buildings have trouble heating on colder winter days, especially when temperatures drop into the 20s for a daytime high. As soon as you reach temperature extremes, building operators often start thinking about operating their buildings overnight.”

Running the building at night will both support freeze protection for your pipes and can increase tenant satisfaction. However, as tenants become acclimated to the colder weather, they may not notice a drop in nighttime temperature, but you will notice savings on your energy bill! Shared spaces, such as vestibule areas and lobbies, loading docks, stairwells, do not need to be excessively heated during the winter, especially in entryways that are constantly letting in cold air. Readjusting the temperature is a great way to avoid excessive costs in non-tenant spaces without any loss in tenant satisfaction.

 

3. Adjust Your Schedule – Building Ventilation

Although ventilation requirements seem counterproductive to efficient operations, there are ways to optimally schedule operations to prevent wasted energy.

Dunfee suggests delaying the start of your ventilation with an economizer during the building’s warm-up recovery time. No occupants in the building means no one will notice the cold air entering the building – instead, tenants will just enjoy the refreshing, crisp air you let in before their arrival. Ventilating the building while starting it up simultaneously will waste a significant amount of energy because the heating system is fighting the outside elements. Plus, the building will take much longer to reach its ideal temperature. Sometimes, it’s actually better to start your building a few hours early, so it can completely warm up before you start introducing outside air into the building, making it easier for the building to recover.

Each building varies greatly, so strategic winter operations must consider the individual building’s needs. However, you can certainly investigate what your ventilation schedules are, why they work that way, and how you can adjust your operations for optimal winter efficiency.

Want to quickly pass these tips along to your team? Start the conversation by asking them these questions:

 

1. Is your building’s HVAC system ready for winter operations? Does it need to be tested and calibrated before the winter?

2. What is nighttime setback schedule? Has this strategy been optimized for winter?

3. Is your building prepared for freeze protection?

4. When is your building being ventilated? Is the schedule optimized for the cold months ahead?
 

Lee Dunfee and Samantha Dubrow contributed heavily to this post.
 

 

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About The Author

As the Digital Marketing Specialist at Aquicore, Kelia Cowan manages the company’s content and events, including the company blog, social media channels, resources, email marketing campaigns, webinars, and conferences. Simultaneously, she fields questions on how to “properly” pronounce her name.

Previously, Kelia was the Marketing and Communications Fellow at Cleantech Open Northeast, where she focused on digital content and event coordination. As an undergraduate student, she worked in various communication roles at Dana-Farber Cancer Institute, The Green Party of Aotearoa New Zealand, and Energy Excelerator. Kelia left the paradise of Honolulu, Hawai’i, to attain a B.S. in Journalism and a B.A. in Environmental Analysis & Policy from Boston University.