BAS Schedule Control: Simple but Best

allan-brain-on-building.jpg

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.

e-sf1after

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.

 

 

Mike at Home: The Sequel

When Ontario is giving out free smart thermostats, you know it’s time for a blog! Most of my recent blog posts have been about projects at UHN, so this time I’m going to change it up and talk about a couple of neat technologies I’m using at my apartment to save energy. Both of these savings ideas were mentioned in my previous Mike at Home Blog, but these new technologies really help to put those ideas into practice in a convenient way. There are many ways to save energy at home, even if you are a renter like me!

Smart Thermostat

I already had a programmable thermostat which was helping to save energy, but I wasn’t able to maximize savings for a couple of reasons. One way I typically try to save power is by setting back the thermostat if I’m away for a weekend or longer vacation, however this often led to an uncomfortably cold temperature for a few hours upon return. When energy savings lead to discomfort it can be difficult to maintain the energy savings behavior and I may have been less consistent in doing the temperature set back as a result. With my old thermostat on the fritz, I took the opportunity to upgrade to a web-connected thermostat.

TH1120RF-40001

New Thermostat (source)

Continue reading

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
urbantoronto-9929-35158

Krembil Discovery Tower (Image Source)

Background

Continue reading

The Sixth Sensor – I See Live People!

Looks like I might be starting a trend referencing old 90’s movies on the Talkin’ Trash blog. This time, with Halloween fast approaching, we are taking a spookier turn as we look at the recent stairwell lighting project at TRI University Centre.

6th sense quote

If you want to hear something really scary, Continue reading

UHN: A Medical Innovator, But Also An Energy Innovator

My previous blog described a unique energy conservation project at UHN’s Princess Margaret Cancer Research Tower (PMCRT). With innovative contaminant sensing technology, we were able to convert our research lab exhaust system from constant flow to variable flow, which significantly decreased loading on the exhaust fan motors. As described in the blog, this change produced a reduction in electricity peak demand (kW) of 38.5% and reduction in overall annual electricity consumption (kWh) of 42.7%.

We thought this was a Continue reading

Say Hi to Allan, our new Building Control Specialist

allan-wu Continue reading

Savings at PMCRT will Blow You Away!

mars_banner2014-700-x-385

Princess Margaret Cancer Research Tower. Photo Credit

Next in our list of exciting energy endeavors, this blog will discuss huge savings realized by a retrofit to the laboratory exhaust system at the Princess Margaret Cancer Research Tower (PMCRT). The lab exhaust system has been converted from constant speed to demand controlled to ensure more efficient operation. I’ll get into all the super interesting details below, but the best part is the savings so I’ll start off with that. Continue reading