Commercial Efficiency Trends are Holistic
December 28, 2009
When it comes to efficiency, the savings can exceed the amount of effort it takes to make these changes. It stands to reason that an efficiency-improving system that addresses a commercial mechanical plant as a whole can save much more energy than modifications made to single components.
This is the philosophy being followed through the technology of Optimum Energy HVAC. The company’s technology monitors and tracks the entire HVAC plant in commercial applications, so that components that go outside of their normal parameters set off alarms - letting contractors know about potential efficiency and operational problems before they are apparent to building owners and tenants.
PREDICTIONS“I think over the next three or four years we’re going to see a convergence of IT and BAS,” Rothman predicted. Considering the skill sets that will be required, having a plug-and-play product will be a real advantage.
“Owners are starting to see that HVAC is a controllable aspect rather than a fixed expense,” said Nathan Rothman, founder and CEO of Optimum Energy HVAC. The company works with commercial HVAC contractors to provide energy solutions to their customers. “Buildings are greener, and we’ve seen that green buildings command a slightly higher rent. By running everything slower, the life of the equipment is extended.”
When the company’s services are proposed, “The contractor tells us what’s in that plant,” Rothman said. “We tell him what we think the savings would be, and this is what we believe needs to be done to that plant. Then the contractor figures out his cost to do it. If the customer is ready to move ahead, we want to send an engineer out there - see that what’s reported to be there is there, talk to tenants, and rebalance the air side.”
The timing is right for products and services like this. In addition to the stimulus plan, various clean energy and climate bills currently being debated on the Hill are bringing energy efficiency to the top of public consciousness. Global consulting firm McKinsey & Co. estimates that 40 percent of the pollution reduction needed to prevent catastrophic global warming can be achieved through efficiency improvements alone.
Under that backdrop, Optimum Energy has been following these leading green trends throughout 2009:
• States are increasingly enacting clean energy mandates, driving building owners and consumers to be mindful of their carbon footprints, and, in some cases, especially in commercial buildings, retrofitting buildings for operational efficiency.
• While more and more commercial buildings are retrofitting existing building structures, new buildings are becoming more concerned with operational efficiency and are implementing green mandates.
• A new category of green computing - operations technology - has emerged. This new operations technology category considers the lifecycle of intelligent buildings and how the convergence of operations with information technology (IT) can drive unprecedented improvements in building performance.
• Smart Grid and Demand Response is driving job growth and is realizing increased funding for projects.
HOLISTIC TECHNOLOGYOptimum Energy (a Seattle-based company) has been able to develop its technology as a fusion of IT and building automation systems (BAS). According to Rothman, “By operating HVAC systems at a new level of efficiency, we can reduce electricity usage 30-60 percent.” The products also can reduce water usage, extend equipment life, reduce carbon emissions, and earn LEED points. So far, it has been applied in more than 60 commercial and government buildings.
The technology uses Web-based measurement and verification programs to track usage and performance, Rothman ex- plained, applying the maxim, “Every penny counts.” The programs allow contractors and Optimum Energy to view plant operation in real time. “In all plants we guarantee and verify our results,” he said. The system is said to provide ultra-high-performance HVAC.
The products use kW/ton efficiency measurements. According to Rothman, a typical building’s chilled-water side accounts for 90 percent of the load; 10 percent comes from the hot water side. By improving overall system efficiency, he said, it doesn’t matter if the load increases; the efficiency remains the same.
There are three main products at this time. OptimumLOOP product addresses efficiency readings in the chiller plant and cooling towers. OptimumTRAVE deals with VAV air-handling equipment. And HVAC Performance Assistance deals with measurement and validation for both the LOOP and TRAVE.
PART-LOAD WORLD“This is a part-load industry,” said Rothman. “If I’m a good engineer, I’m designing for the top of the load plus a little extra.” However, 98 percent of the time the system is operating at partial load conditions.
A large part of the products’ efficiency improvements come from more efficient use of variable-speed systems, which are integral to the technology. “We want all variable-frequency drives,” Rothman said. “We want VFDs put on all the pumps and cooling tower fans.
“The way it’s been done over the past 10 years or so, they’ve been putting VFDs on the pumps and fans,” he said. “Then they write code for how they think they can maximize efficiency.” The more efficient way to do it, he said, has to do with the affinity law of physics, which says that if you reduce the speed of an electric motor driving a fan or a pump, you reduce consumption by a factor of three.
The company looks at its technology as being like an orchestra conductor. “Our technology says, ‘OK, if we look at all the equipment operating and look at the load, what is the most efficient way to operate the plant to meet the load? How can we run all these different pieces of equipment to use the least equipment, and change to meet the varying load?’ We’ve developed a number of algorithms that quickly calculate this.”
In addition, the company claims to have very easy installation. “Our software goes into a microprocessor and plugs into the BAS,” Rothman said. “It’s plug-and-play.”
He said the system gets HVAC plants to operate at 0.5 kW/ton - the entire plant, not just the chiller. A measurement verification dashboard trends, collects, and saves the data. It includes indications of how the equipment is operating, and includes measurements that might indicate other performance problems - for instance, that chillers might be fouling, bearings are starting to go, filters are loaded, etc.
“The contractor can see it, and I think we can improve or lessen the roles of the trucks,” Rothman said. “We can diagnose 86 to 96 percent of the problems by looking at the information we provide.” Trucks then can be sent to the jobsite with the specific equipment needed; diagnostics are performed largely with these measurements. The contractor can then address problems before the customer perceives them.
“One of the things that we’ve learned,” he said, “is that when we get these plants running, other problems in the plant are revealed to us and the owner.” For instance, in one case poor cooling in specific sections of a mall were diagnosed as pipes that were too small after the Optimum Energy system was applied. The tenants had been living with the problem for years, and the contractor was “fixing” it with spot coolers. A long-standing problem was resolved for the tenant.
“We’re the last component in the equation,” Rothman said. That being the case, it’s important that the installation can be accomplished quickly and accurately. The technology reaches out to digital signals in the system, gathering operational feedback from VAVs, thermostats, etc.
After the system is installed, clients are notified within five minutes if there’s any type of fault in efficiency or operation. “If a pump goes down,” he said, “we’re going to know immediately. If the efficiency falls, we’re also going to alarm. A dirty filter will show up in the fan operation.
“That’s where our trending comes in,” he said. “Over time we would see degradation in the airflow.” Maintenance is therefore based on actual operating parameters instead of working off of a maintenance schedule. “We have predictive and ongoing maintenance.”
Regarding controls compatibility, “We want to be like Switzerland,” said Rothman; “we want to be vendor neutral. We just want buildings to be better.
“I think the new company coming out of all this is socially responsible,” he concluded. “And the customers save money, so there’s a huge business benefit.”
For more information, visit www.optimumenergyhvac.com.
Publication date: 12/28/2009