Energy

HVAC Advances

Using innovation to enhance efficiency and occupant comfort

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Not only has HVAC technology undergone changes yielding greater efficiencies, but the way building owners and operators are able to leverage the changes to improve the bottom-line and occupancy comfort is seeing a boost.

“These days, we are starting to see HVAC solutions taking the Facilities as Strategic Assets approach,” says Dan Diehl, CEO, Aircuity. “Vendors and end-users who adopt this approach view facilities as strategic assets that must be managed to drive the success of the core business.

“Their goal is to manage the design, maintenance, operation, and retrofitting of buildings to measurably improve business—not just building—outcomes. This is one more rung up the value stack from solutions that leverage data and analytics to provide guaranteed service level agreements, in which the customer pays a variable fee based on verified outcomes achieved and sustained.”

One driving factor, says Diehl, is the WELL Building Standard, a performance-based system for measuring, certifying, and monitoring features of the built environment that impact human health and wellbeing, through air, water, nourishment, light, fitness, comfort, and mind.

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It is managed by the International WELL Building Institute, a public benefit corporation focused on improving human health and wellbeing through the built environment.

Diehl notes that with the rise of the standard and the recent COGfx Studies, “we are seeing end-users looking for HVAC solutions that help improve the indoor environmental quality for occupants in addition to just saving utility dollars,” says Diehl.

In the COGfx (cognitive function) study, researchers at the Harvard University T.H. Chan School of Public Health’s Center for Health and the Global Environment, SUNY Upstate Medical University, and Syracuse University studied the effects of improved air quality with primary support from United Technologies and its UTC Climate, Controls & Security business.

They found that an improved indoor environment doubled participants’ scores on cognitive function tests. Employee cognitive performance scores averaged 101% higher in green building environments with enhanced ventilation compared to a conventional building environment.

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“The payback for improved indoor environmental quality far outweighs the investment, considering that more than 90% of the costs associated with a building are related to the people who work within it once construction is completed,” notes John Mandyck, United Technologies Chief Sustainability Officer.

The double-blind study evaluated the participants’ cognitive performance in a laboratory setting simulating those found in conventional and green buildings as well as green buildings with enhanced ventilation.

Of the functional domains studied, the largest improvements in test scores occurred in the areas of crisis response, information usage, and strategy, with crises response scores 97% higher for the green environment and 131% higher for the green environment with enhanced ventilation and lower carbon dioxide levels compared to the conventional environment.

The results suggest that indoor environments can have a profound impact on the decision-making performance of workers, a primary indicator of worker productivity, says Dr. Joseph Allen, assistant professor of exposure assessment science at the Harvard T.H. Chan School of Public Health, director of the healthy buildings program at the Center for Health and the Global Environment at Harvard Chan School, and the study’s principal investigator.

Solutions that optimize ventilation based on multiple parameters are capable of impacting employee productivity, a company’s bottom-line, and in turn, a company’s mission, Diehl points out.

“These solutions also allow building managers and owners 24/7 access to view intelligent data on IEQ so facility managers and building owners know exactly what is going on within the office building,” he says. “This helps ensure a healthy and safe working environment and data can be used to proactively address issues.”

In 2012, Michigan State University (MSU) created an energy transition plan targeting a 65% greenhouse gas emission reduction through energy efficiency initiatives and increased use of renewable energy sources by 2030.

After laboratory facilities were identified as the largest energy users on campus, MSU formed a cross-functional Safe Sustainable Lab Committee, the objective of which is to balance safety and energy efficiency while working towards university targets.

The first goal of the energy transition plan was to improve the physical environment through assertive investments in energy conservation measures.

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In 2008, Ingenuity IEQ introduced MSU to its channel partner Aircuity in 2008 through an installation in MSU’s food science and human nutrition building. Aircuity offers an intelligent building platform designed to significantly reduce energy costs and improve the indoor environmental quality for occupants.

As a demand control solution, Aircuity optimizes ventilation rates through its technology that is designed to lower operating costs, protect occupants, and reduce energy use by as much as 60 percent for commercial, institutional, and lab building owners.

Seeking to engage a solution that impacts safety and energy efficiency and based on several prior Aircuity installations that had already created measurably improved campus environments, the university chose the company for an integrated design approach for the Safe Sustainable Labs Concept.

MSU’s airside program now consists of 268 lab installations in seven buildings that have yielded more than a half million in annual savings. The ROI on the various lab installations has ranged from 1.5 to 5.3 years.

MSU’s Environmental Health and Safety (EHS) personnel have the ability to closely monitor events occurring in the space.

“EHS regularly monitors the Aircuity dashboard to get a quick look at many laboratory environments, something we couldn’t do without contaminant sensing,” points out Dave Erickson, senior industrial hygienist for the EHS office.

“We can see and verify air change rates increase in response to contaminants generated in laboratories where normal operations regularly and continuously generate low levels of VOCs. We also use the dashboard to scan for high peaks of VOCs, particulate, or CO2 in unexpected locations and follow up with a site visit. In one case, we found an incubator leaking CO2. Another application of the Aircuity dashboard is investigation on problem calls.”

In 2013, MSU’s Anthony Hall was selected as a showcase project in the US Department of Energy’s Better Buildings Challenge. The 317,200-square-foot building houses the Department of Animal Science and the Department of Food Science and Human Nutrition as well as the university’s Meats Lab and Dairy Store.

A blend of more than 10 carefully selected energy conservation measures, including Aircuity, was installed in the building with an expected annual cost savings of $536,000. Aircuity was installed in 8.7% of the building and yielded about $128,000 in annual energy savings, one-quarter of the total energy savings derived.

In addition to lab spaces, MSU has implemented Aircuity in other campus buildings. In 2016, Aircuity was installed in the vivarium area located in C Wing of the Clinical Center which functions as an animal holding area. Aircuity has reduced air change rates from 10 to 4 ACH.

As with all Aircuity installations, the ventilation is increased at times when an event is detected and additional air is required. As a part of the Safe Sustainable Labs design concept, Aircuity provided EHS additional means to closely monitor the labs while the energy saved through Aircuity is helping the university to meet its energy transition plan GHG and energy reduction targets.

The university plans to expand its airside program with installations in additional lab buildings.

In Ontario, Canada, the existing two-pipe chiller system in the Sheraton Centre Toronto­—a 443-foot-tall, 1.5-million-square-foot building—had only allowed for either heating or cooling.

The deteriorating system was not providing the ability to heat and cool rooms independently. A replacement system was required to integrate with existing building controls and comply with CSA B52 refrigerant limitations.

The Sheraton Centre Toronto Hotel consists of two main buildings—the 43-floor Queen Tower and the 11-floor Richmond Tower. The two buildings share a common lobby and a connecting concourse at the second-floor level.

The hotel underwent an extensive $120 million renovation of the entire property, including all 1,373 guest rooms, suites, conference rooms, and public areas.

A Daikin VRV system was chosen to address the HVAC challenges. The decision was based on the system’s ability to operate in heating and cooling modes simultaneously between guest suites.

The Daikin VRV system also operates at lower sound levels, and provided a competitive total installation cost compared to other options.

Daikin VRV air-cooled heat recovery systems are designed to provide simultaneous heating and cooling from a single outdoor condensing unit to multiple indoor fan coils and have an extended heating capacity operating range down to -13°F (-25°C) as standard.

The unit is engineered and optimized for Total Cost of Construction and Life Cycle Cost and part load efficiencies are optimized using dedicated all-inverter compressors and inverter fan motors.

This allowed engineers to design air-cooled VRV systems without any backup heating as long as the condensing unit’s size met the heating load at the design temperature.

The heating design temperature used on this project was -4°F.

At the Toronto hotel, the existing two-pipe fan coil system was replaced with Daikin VRV water-cooled heat recovery systems. Three Daikin VRV water-cooled systems with two condensing units each were installed for every two floors to provide approximately 20 tons of heating and cooling per floor.

Ten Daikin VRV air-cooled heat recovery condensing units also were installed on the roof for 54 of the guest suites.

The refrigerant piping layout is similar for both the water- and air-cooled systems. Each pair of condensing units forms one system, offering redundancy. Each system contains three refrigerant lines installed above the hallway ceilings with a tee off into each guest suite.

The lines are connected to a small single-port branch selector box installed next to the fan coil in the bathroom ceiling. All suites are retrofitted with 8-inch-tall slim duct fan coils, with precisely balanced direct drive fan assemblies.

The installation fits above the ceiling just outside the tub/shower area.

There is a second level of heat recovery on the water-side with the Daikin VRV water-cooled systems.

Daikin partnered with INNCOM to integrate with the hotel’s existing building management system. The joint development included the installation of INNCOM thermostats wired to VRV indoor units via a PC-RTD adapter.

The adapter provides INNCOM thermostats with eight points to monitor and control the indoor units in each suite without the loss of Proportional Integrated Derivative control or system efficiencies.

Thermostats in each suite react to the rental and occupancy status of the suite.

The combined technology of INNCOM and Daikin VRV provide cooling and heating only when and where it is required.

The combined INNCOM energy management and Daikin VRV Heat Recovery systems are designed to maintain a quiet, comfortable room temperature while ensuring maximum operation and efficiency are fully achieved.

Both 12-ton and 14-ton dual module systems along with single port branch selector boxes with Refnet piping joints keeps refrigerant charge low and in compliance with CSA B52 refrigerant limitations.

For the air-cooled systems, a refrigerant riser from the roof-mounted units serves each system’s respective floor.

In the Queen tower, existing storage room areas on each floor were converted to small mechanical rooms. In the Richmond tower, ice machine rooms were remodeled to allow space for both the ice machine and a mechanical closet. The mechanical closet houses the stacked VRV water-cooled condensing units.

The hotel’s existing condenser water lines—which run from the basement mechanical room to the roof-mounted cooling towers—are used to feed the VRV water-cooled condensing units on each floor.

The equipment used included:

  • 136 VRV-WIII water-cooled heat recovery condensing units
  • 10 VRV III air-cooled heat recovery condensing units
  • 1,380 indoor Slim Duct concealed units
  • 35 indoor wall mounted units
  • 1,380 branch boxes
  • 1,373 INNCOM Honeywell thermostats
  • 1,373 PC-RTD INNCOM interface adapters
  • 35 BRC1E73 Navigation Remote Controllers
  • 8 DMS502B71 DIII-NET BACnet interface
Credit: Entic
A remote energy center

The team included general contractor Gillam Group of East York, mechanical contractor Modern Niagara of Toronto, and consulting engineer M & E Engineering of Concord—all from Ontario, Canada.

The ability for building owners and operators to manage the properties with remote cloud-based services based on high-level analytics is bringing increased efficiencies to HVAC systems, points out Jorge Hernandez, director of energy services for Entic.

Entic’s cloud-based technology provides a subscription model for the use of operators and owners, offering them the ability to see, predict, and prescribe corrective action year-round. The operational intelligence is extended through energy-consuming systems including HVAC, lighting, and water using wireless sensors, computational analytics, and data science.

What Entic offers is a differentiator in the amount of data the company has amassed over time and how it is integrated into a facility through sensors to produce analyses, says Hernandez.

Data is turned into actionable insights through data collection via BMS and Entic sensors, which leads to system detection visuals and analysis of device performance over time and at a glance and helping to establish prioritization of issues.

Diagnoses are derived from correlating symptoms and identifying the causes and the impact. Prescriptive measures are delivered and recommended actions are tracked, all of which is designed to lead to avoided energy costs.

All processing requirements are performed by Entic’s cloud-based platform. Its dashboards are accessed via any web browser, mobile device, or tablet. Unlimited text, phone, and email alerts are set to customer-defined fault classifications and excess energy usage thresholds.

The smart technology provides data that identifies the location of equipment inefficiencies, which can prompt a building operator to do resets to such areas as air temperature or chilled water—“those factors operators aren’t thinking about on a regular basis or they know nothing about,” notes Hernandez.

Entic has created a number of internal studies based on various building applications that enable the company to prescribe data-based changes that are historically successful and sustainable, he says.

The cloud-based system is of benefit in that “it could become cumbersome for the onsite staff where they have to maintain the server, keep backup, and all of those things that nobody thinks about with the HVAC equipment,” says Hernandez, adding that the benefit is especially useful to buildings with antiquated systems.

There are buildings that “don’t necessarily have in-house expertise” in the way the Entic system presents the data offering information on where a system is in real time and where it needs to be to derive better efficiencies, Hernandez says.

Costs are attached to identified items such as the air handler, chiller, cooling tower, or pump. The system informs building operators about forgotten overrides, Hernandez says. The system’s dashboard offers the ability to scale and demonstrate the results in making the data relevant to the space. It has derived an 8–12% energy reduction across the company’s portfolio, he adds.

End-users appreciate the scorecard provided from an enterprise level that drives initiatives on data-based decisions with favorable ROIs, which may come in less than two years, Hernandez says.

Within the first year of implementation at the Park Avenue Tower in New York City, building operators saw a 787,000 kWh or 16% reduction in electricity consumption, a 16% reduction in electricity costs of $149,500, a $2.98 million asset value creation based on a 5% cap rate, and 90% resolution on prescriptions issued by Entic.

“I have no spend on any prescriptions to date,” says Anthony Muoio Jr., chief engineer at Park Avenue Tower. “Resolutions have been at no cost by either making adjustments to our operations in house or having our vendors assist during routine maintenance.”

What he sees as the biggest challenge in the HVAC space is when maintenance costs are cut out, says Hernandez, adding that the lack of maintenance is the leading cause of inefficiencies.

Through leveraging data that emanates from analytics into formulating maintenance plans, building operators avoid the surprises that come with the utility bill, he adds. BE_bug_web

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