BAS Schedule Control: Simple but Best

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Almost all buildings, in particular hospitals, have a Building Automation System (BAS). It’s is like the brain of a building. BAS controls most HVAC devices, such as pumps, fans, boilers and chillers. It is an interconnected, centralized system of both hardware and software, like a central nervous system. BAS provides lots of benefits, including the ability to control your building from anywhere and improved energy management. It automates all your heating, cooling and air flow needs with minimum interference.

BAS

Quite a lot operators, supervisors and facility managers leave the fans and pumps running continuously. This might seem like a good idea  … the system works all the time and users would not complain any more. But this is not a good practice as the constant use will wear out motors, belts and pumps before their time. Maintenance cost will rise and the utility bill will rise even higher.

Like people, building systems need a break. The best way is to check how people use a building, and see if we can schedule control changes for the area. If an area is only used some of the time, say during business hours, we know we can power down HVAC units after hours.

We have to make sure the unit could be turned on when needed. For example, if the air handling unit is set to unoccupied mode, it does not supply any conditioned air to the space, but it will restart when the space temperature drops below the unoccupied heating setpoint or unoccupied cooling setpoint. Only when there is a good backup plan can users feel comfortable and support these energy-saving scheduling initiatives.

With schedule control, devices will run for less time. Usually we can turn it off over the weekend. Even if we need to run the unit 12 hours a day, from 7am to 7pm, we could still save 65% on the electricity of the motor. The savings grow when we factor in gas for heating or electricity for cooling.

Below is a simple trend chart for a unit.

As the unit was running continuously before, the electricity consumption was 170,792KWh annually.

E-SF1before

After we implemented a weekday schedule, the power consumption dropped to 60,830 KWh. The users did not feel any difference.

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Schedule control on an HVAC device is a straightforward and most efficient way to save energy. It could also extend lifetime of the equipment itself. That’s saving 2 ways … a real no-brainer.

 

 

You down with DCV at KDT? Yeah you know me!

Whether you want to send a car to space or implement an energy project, you must measure and track results! One of the biggest things we do here at the Energy and Environment team is to measure and track project results because it gives us real world information that we can use to accurately evaluate similar projects in the future. This post is about the recently completed demand controlled ventilation (DCV) project at the Krembil Discovery Tower (KDT). This project follows in the footsteps of similar projects that we worked on with UHN Research at the Princess Margaret Cancer Research Tower (PMCRT). Since we had such good proof of concept results from PMCRT, it made for a much easier decision to proceed with the project at KDT. Let’s take a look at the project and results!

Here’s a preview of the savings for those that don’t have time for all the details:

  • Electricity Demand Savings: 310.6 kW (equivalent to about 630 window AC units)
  • Electricity Consumption Savings: 1,433,353 kWh (equivalent to 161 typical Canadian houses annual consumption)
  • Natural Gas Savings: 418,343 cubic meters (794 tons of CO2, equivalent to taking 169 cars off the road)
  • Utility Cost Savings: $241,337
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Krembil Discovery Tower (Image Source)

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District Cooling Retrofit at Toronto General Hospital – Saving Money While Improving Infrastructure

District Cooling Retrofit at Toronto General Hospital – Saving Money While Improving Infrastructure

Toronto General Hospital is undergoing a major retrofit of its central chilled water plant, one that will fundamentally improve the system’s capabilities and dramatically reduce electricity costs.  The plant is essential to services at the hospital, providing chilled water to equipment and ventilation.  It cools operating rooms, equipment for MRI and CT scans, servers, rooms with -80ºC freezers, the cyclotron, as well as all the clinics, patient rooms, and offices throughout TGH’s two million square feet.  The new system will save the Continue reading

Grizzlies, Mountains, and Sustainability! Reporting from the CHES Conference

Grizzlies, mountains, and sustainability! Earlier this week, I had the opportunity to attend the Canadian Healthcare Engineering Society (CHES) annual conference, hosted in beautiful Vancouver. The theme of this years conference was sustainability in healthcare. This theme refers to both systemic sustainability and environmental sustainability, with the goal to preserve health care services as well as the natural environment so that you’ll be able to get a timely appointment for your tennis elbow injury suffered during a round of frisbee golf and so that grizzlies can continue to survive in their natural habitat.

UHN had great Continue reading

Little Choices for Little Futures

Being a new Dad has given me a lot to think about, but you probably already knew that. Like in this picture perhaps. I used to just put on a jacket and go outside, now….. I make a hundred decisions before I go out the door. “Stroller or carrier? Is she warm enough, can she breathe, is she still breathing, do we have the diaper bag, are there actually diapers in the diaper bag, how long will we be gone, wait where are we going?”.  Those are my immediate concerns, but what about the future?  What about long term?

What about in 30 years when my daughter is my age?  (insert nervous gulp here)

Kara Month 2 - 7

Will we be Continue reading

T8: Retrofit Day

Come with me if you want to saveYes, I am from the 90s when Terminator 2: Judgement Day was the coolest thing since sliced bread.  Since then, Continue reading

What do you love? The best Trash we were Talkin’ in 2015

Ah, end-of year lists. Love ’em or hate ’em, it’s fun to see the cream of the annual crop rise up. Thanks to the power of analytic tools, we know what you’ve been reading (or not), so this list is entirely on you. Here we go, looking back at our top stories (which you can jump right into with the click of a pic). They’re grouped thematically, not numerically, and it really says a lot about you, our lovely readers. Speaking of cream…

You care a lot about energy conservation (and donuts and contests) …

 

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Ever wonder how many donuts equates to the energy used by leaving your computer on during the weekend? Mmm … donuts. We also chose our #NameMyTLC winner: “Turn it Off Before You Go-Go”

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