Category: Tech Tips

Energy Management Case Study: Retro-Commissioning Service Cuts Energy Use

Two prominent grocery chains in the Upper Midwest are reducing their energy use and cutting energy cost by retro-commissioning their stores. The chains have done so with the help of SINGH360, a service provider that specializes in working with grocery chains, and the PowerScout 24 power meter.

The retro-commissioning process identifies opportunities to improve energy efficiency for stores that have been in operation for several years. The process is valuable because such stores tend to become less energy efficient with time, says Abtar Singh, president of SINGH360.

Strack and Van Til, a 37-store chain in Indiana and Illinois, recently hired SINGH360 to retro-commission 16 locations. As part of that process, the company upgraded system controllers to the latest software version. They put the energy-management system (or EMS) for each store on a network so that they can check and manage them remotely. They also implemented a system to control store lighting on an Energy Management System.

“In the last four months we’ve seen savings of 8% to 12% on average,” says Don Erminger, director of energy and maintenance. “Before the project, we expected a payback of two years. But after our first four months, we now think we’ll achieve full payback in 12 to 14 months. That’s twice as fast as we first projected, thanks to opportunities SINGH360 identified.”

Coborn’s, a 54-store chain headquartered in St. Cloud, Minnesota and operating in six states across the Midwest, recently retro-commissioned its first store. In addition to reducing energy costs and improving environmental sustainability, the company also benefited from addressing many maintenance issues, says Chris Braun, refrigeration project manager.

With the opportunities SINGH360 identified, plus a 75% utility incentive from Dakota Electric, the company expects payback in less than six months, Braun says. The project also identified added capital projects that could cut the company’s energy use by 20% to 25% during retro-commissioning, he says.

Such utility rebates often make retro-commissioning even more attractive.

Xcel Energy (http://www.xcelenergy.com/), an electric and natural gas utility that serves customers in eight states, provides attractive incentives for its customers. “Recommissioning can be a good way for supermarkets to save energy,” said Renae Wrich, Xcel Energy recommissioning program manager in Minnesota. “As an incentive for supermarkets to take action, we offer rebates to subsidize the cost of identifying and implementing energy-saving HVAC and refrigeration projects,” She said. Xcel offers recommissioning rebates in Colorado and Minnesota.

SINGH360’s retro-commissioning process is especially tailored to the needs of supermarkets, says Abtar Singh, president.

“We always involve a three-person team. They include a commissioning engineer, a refrigeration technician, and an electrician. They use a mobile app we developed to make the process thorough and consistent.

A DENT PowerScout 24 was used to submeter the mains, lighting, HVAC, refrigeration compressors, and condensers. The submetered data helped in three ways during the retro-commissioning:

  1. To quantify energy savings achieved during retro-commissioning
  2. To identify anomalies and help determine that lighting and HVAC were operating on the proper schedule
  3. To find optimum operating control parameters for the refrigeration system using the metered data

“The building owner uses that same data to protect their savings by continuous monitoring,” says Singh. “We selected the PowerScout because it provides easy installation and provides a rich set of data, such as voltage, current, and power factor.”

Each store takes about three weeks to recommission, Singh says. “First we dial in remotely to analyze the store’s energy management system (EMS). We prepare a game plan. Then our team spends a week in the store diagnosing and fixing problems. While we’re on site, we also fine-tune the EMS.”

“Then we further adjust the EMS remotely and monitor its performance to verify the changes are producing their intended effects,” Singh says.

“We create an issue list so the store owner can hire a refrigeration contractor to fix any problems that go beyond the solutions we provide. We also identify additional energy projects and initiatives that can further reduce energy consumption.

“Finally, we issue a commissioning report. The report summarizes the work we’ve done. It identifies and recommends new opportunities for savings. And it forecasts likely savings from the recommended projects.”

About SINGH360 Inc.

SINGH360 (www.singh360.com) specializes in facility management. The principals have worked with the supermarket industry for 20 years, providing objective counsel that helps operators find and implement the best solutions to energy and maintenance challenges. The company’s solutions often incorporate the latest technologies. Services range from building-envelope assessments to complete design of mechanical and electrical systems (including HVAC, lighting and refrigeration systems) for new and existing buildings. The company help organizations set priorities for efficiency projects based on sustainability goals, speed of payback, and the return on investment. For more information, contact Abtar Singh, abtar@singh360.com or 651-605-1093.

Save Time + $$$ on Your Next Project: FREE Energy Metering Guide!

As an energy manager, you know one of the fastest ways to start saving on building and equipment costs is to perform an energy audit to identify savings opportunities. Unfortunately, that is sometimes easier said than done. Not only do you need to figure out the right metering equipment for your project, the installation itself can be tricky, too…

Did you know that one of the easiest ways to save money on your next audit was to simply be organized about the installation itself? A little planning can mean the difference between having the correct equipment before the site visit and multiple trips to a site to correct costly installation errors.

Multiple Site Visits = Time and $

For your next metering project, stay organized! The DENT Engineering Team has assembled a step-by-step Metering Project eBook to help you with your next project. Whether you’re facing your first metering project or you’re an experienced auditor, you’re sure to find useful planning information for your future projects. Don’t let important project details slip through the cracks – use the handy checklists in the guide to stay on track. 

Stop Overpaying the Power Company: Energy Audits are Key to Savings

Most companies want to decrease their energy consumption, either for financial reasons, or to be active in reducing their carbon footprint, or both–but some of them aren’t sure where to begin. When the only measure of a facility’s energy usage is the bill customers receive at the end of the month, they may feel their facility is more like the proverbial black hole: power goes in, business happens inside, but it’s not clear exactly how much energy is used where and when. Factory owners may want to know where the heavy usage is inside their plant–how much consumption is used to operate compressors, chillers, pumps, lighting, etc. Office building owners may want to break out the energy consumed in their HVAC vs. lighting systems.

To get an accurate breakdown of energy consumption, a common method is to conduct a short-term energy audit. In an audit, monitoring devices are installed for a period of time to measure all the circuits that are responsible for the overall energy usage of the facility. The resulting data are recorded, demonstrating what areas are consuming the most power. By comparing the consumption of these with industry averages, it’s possible to identify areas where energy can be saved. For example, lighting energy usage that is higher than typical for a business of its size could mean that the facility has unnecessarily high illumination levels or lights in use when not necessary.

When starting an audit, there are many areas of a building that need to be investigated for potential savings. A good building energy audit will indicate how to reduce your energy costs by 10% to 40%, depending on the building. Energy audits typically focus on the following areas within a facility:

  • Lighting Systems
  • HVAC Systems and Controls
  • Compressed Air Systems
  • Renewable Energy Applications
  • Electric Motors and Drives
  • Process Systems
  • Steam Systems
  • Heat Recovery
  • Building Envelope Upgrades

A variety of tools are part of every energy auditor’s toolkit. These items may include an infrared camera, digital pressure and flow gauges, a gas leak detector, a carbon monoxide detector, a combustion analyzer, a moisture meter, and others.

But to determine if there has been a reduction in energy consumption, a recording power meter is also required. For example, the DENT ELITEpro XC, can capture kWh/kW energy and demand data as well as many other relevant energy parameters for diagnostics and monitoring on three-phase or single phase systems. The ELITEpro XC is also ideal for capturing baseline energy consumption before any changes are made to an energy program. This baseline information is crucial in determining the success of any program.

In many cases, a load study can last for a month or more. If a recording power meter is not already part of your toolkit, or if the study is a one-time event, the smart choice may be to rent this equipment instead of purchasing.

DENT Instruments has a network of authorized distributors around the United States, some of which provide equipment rentals. If your next project is short term, give the distributor in your area a call for rental pricing. In addition to the equipment, they are a fantastic resource for advice on how to get started with your measurement project.

HERE ARE THE DENT AUTHORIZED DISTRIBUTORS WHO RENT EQUIPMENT:

        HANOVER TECHNICAL SALESMain Office: Virginia800-304-9043sales@hanovertechnical.comWebsite: http://hanovertechnical.com/
     PANEL COMPONENTS & SYSTEMS (PC&S)Main Office: New Jersey800-523-9194Bill Renshaw (ext 19): bill@pc-s.comRon Aloisio: raloisio@pc-s.comWebsite: http://www.pc-s.com/
 LAKELAND ENGINEERINGOffice Locations: Minneapolis (HQ), Denver, Kansas City, Omaha1-855-544-0321meck@lakelandengineering.comrkucksdorf@lakelandengineering.comWebsite: https://shop.lakelandengineering.com/brands/dent-instruments
 PQ TESTING & RENTALSMain Office: Florida407-421-0846pqtesting@yahoo.comWebsite: http://www.pqtesting.com/

Selecting a Power Meter: Find the Right Tool for the Job

“I need a meter.”

This is where the majority of customer conversations begin at DENT. When you learn that your project includes metering or logging energy consumption, it’s clear that you’ll need some piece of equipment to make that happen. Here’s a list of questions to help you decide which DENT meter is the right one.

QUESTION 1: HOW LONG WILL YOUR PROJECT LAST?

Is your project a 30-day load study or will you permanently be installing a meter within your building? The answer to this first question often dictates which meter is best for you.

If your answer is a 30-day load study, an energy audit, or a measurement and verification (M&V) project, the ELITEpro XC is a solid choice. The ELITEpro XC is portable and can be easily moved between panels or to a new location at the end of one project. This is why it’s often the best choice for a temporary study.

On the other hand, if you plan on permanently installing a meter for building submetering, tenant submetering, or demand response, the PowerScout 3037 or PowerScout 24 will be more suitable. The PowerScout is hard-wired into the panel (as opposed to connecting with croc or alligator clips), making it less portable than the ELITEpro.

QUESTION 2: HOW DO YOU WANT TO COLLECT THE DATA?

The ELITEpro and PowerScout instruments handle data collection in two different ways. How data is collected will likely have a large impact on which meter you decide to use.

The ELITEpro has 16 MB of on-board, non-volatile memory for data storage. Data is recorded as the metering session continues and, once the session is complete, the user can download the data from the meter using a USB cable, over Ethernet, or Wi-Fi (depending on meter configuration). Data is downloaded from the meter using a program called ELOG. Once downloaded, the data can be analyzed using ELOG or can be exported to Excel.

If you prefer walking up to the logger, connecting a laptop, and downloading your data, then the ELITEpro is the right choice.

By comparison, the PowerScout does not have any on-board memory for data collection. Instead, data is sent from the meter via Modbus or BACnet communications to a separate data logger or building automation and controls system. The PowerScout can use either BACnet IP or MS/TP protocol or Modbus TCP or RS-485 protocol for sending commands or retrieving data.

If your preference is to interface with the meter through your building automation system or via a remote dashboard display, the PowerScout is right for you.

QUESTION 3: HOW MANY PHASES DO YOU NEED TO MEASURE SIMULTANEOUSLY?

Are you measuring single or three-phase loads? How many of each do you wish to monitor simultaneously?

With the ELITEpro or PowerScout 3037, you can measure single phase loads or one three phase load. The PowerScout 24 allows for up to 24 single phase or 8 three-phase or a combination of single and three-phase using any mix of CTs.

If you require on-board memory (ELITEpro), but need to measure more than one three-phase load at a time, using multiple ELITEpros may be your best option.

QUESTION 4: DO YOU REQUIRE REVENUE GRADE ACCURACY?

The PowerScout 3037 is a revenue grade meter with accuracy of 0.2% or better (ANSI C12.20-2010 qualified Class 0.2). The PowerScout 24 is revenue grade with accuracy of 0.5% or better (ANSI C12.20-2010 Class 0.5).

The ELITEpro accuracy is better than 1%, which is ideal for energy audits, load studies, and M&V work.

QUESTION 5: WHY CAN’T I JUST USE A SMARTLOGGER INSTEAD OF AN ELITEPRO OR POWERSCOUT?

Actually…you can, under certain circumstances. But it’s important to understand what the SMARTloggers were designed for and their limitations.

SMARTloggers are time-of-use loggers. They are designed to give you run-time information for a load. There are four different “flavors” of SMARTlogger:

  • CTlogger: Has an external CT for using on energy-consuming devices with a power cord
  • LIGHTINGlogger: Has an internal photo-sensor for measuring on-time of lights
  • MAGlogger: Measures on-time for motors (or anything generating a magnetic field)
  • CONTACTlogger: Has dry contacts for monitoring closures (such as with a door or switch)

Take the LIGHTINGlogger, for example. If you have the LIGHTINGlogger installed in your light fixture, it’s going to sense when the lights turn on and off. It will record that information with a time and date stamp. Once you download the data from the logger using SMARTware, you will see the on/off transitions for the light. Maybe your light was turned on at 12:38 AM and turned off at 12:58 AM. It’s easy to see exactly how long your light was on. Here’s a sample of the data output:

All SMARTloggers work in the same manner, but are designed to monitor other types of loads, as outlined above.

What happens when you want to know how much energy your light was consuming. The logger itself doesn’t tell you this information without doing some post-processing. You can set the connected load’s kW in SMARTware software to make an estimate on energy consumption.

This is the real difference between the SMARTloggers and a true power meter, such as the ELITEpro or PowerScout: The SMARTloggers will only be able to give you an estimate on energy usage based on the time a load is on multiplied by how many kW you input in the software. If your question is, “How long has my pump been running?” and not “How much energy is my pump consuming?” then the SMARTlogger is an excellent choice.

QUESTION 6: I’M STILL NOT SURE WHICH METER TO CHOOSE. HELP!

Give DENT Instruments a call and we will help you find a solution for your project. Also, be sure to download our  FREE Metering Project eBook for time & money-saving tips for your next project. The eBook also features multiple checklists to keep you project on track.

Using the CTlogger to Monitor an Appliance

When performing a measurement of a plug load using the DENT CTlogger, one of the two conductors in a typical appliance cord must be isolated to get a reading on the logger. This is because the two conductors are carrying current in opposite directions—thus the magnetic fields cancel each other out. Splitting the two conductors in an appliance cord can leave an unsightly and possibly hazardous condition.

Now you can use the TOU-PA Wall Plug Adapter. Unplug the appliance, plug it into the TOU-PA and plug the TOU-PA in the wall. One leg of the circuit comes out of the side for easy clamping with a CTlogger. This is a safe, easy, and effective way to use your CTlogger with any plug load.

FEATURES

  • Easily measure current draw of a plug load without splitting any wires
  • In-line Male and Female grounded plug with loop for quick connection of the DENT CTlogger
  • Easily move between plug loads for load surveys

TO ORDER A PLUG ADAPTER, CONTACT DENT INSTRUMENTS.

What Happens to the ELITEpro XC During a Power Outage?

One question that we’re frequently asked is this: “What happens to my ELITEpro XC during a power outage?”

The ELITEpro XC Portable Power Data Logger has 16 MB of non-volatile memory. It’s a line-powered device, which means that it’s powered by the L1 to L2 voltage under measurement.

During a power outage, the meter ceases to be energized because it’s powered by the voltage in the panel under measurement. Although the logger stops recording, the built-in memory means the logger maintains all its records and settings. Once power is restored, the meter will continue to record.

There is a feature in ELOG software to help with this scenario called “Fill Missing Records.” This feature detects gaps in the time sequence of the data and fills the missing records with 0 values. This feature is useful any time there are gaps in the time stamp records.

If you have any other technical questions, please do not hesitate to contact our Tech Support department at techhelp@dentinstruments.com or by clicking the Support button below.