Audits and Adaptation
Energy management systems can help you navigate the changing onsite power and efficiency climate.
Monday, November 26, 2012
By Paul Hull
There must be a good reason for changing anything in our business, whether it is private or public, large or small. Advances like computers have succeeded—not because they are cute or clever, but because they have improved our working environment. Not every gadget or gismo created by engineers has been a success, for the same reason. The change must improve our working conditions.
In Kansas City, KS, at the Piper Unified School District, the good change is seen in savings of more than $70,000 per year through an energy efficiency and infrastructure program undertaken by ConEdison Solutions. School officials report $70,834 in annual energy savings achieved through the program, plus $185,667 in non-energy-related savings.
“Every dollar saved goes towards improving the quality of education for the students in our district,” says Steve Adams, superintendent for Piper Unified School District. The district needed to combat space constraints by adding new facilities to accommodate growth, while maintaining the integrity of existing facilities. One part of the program had the high school renovated and expanded with a 30,000 square-foot wing, while other structures benefited from much-needed infrastructure improvements. How can a school district afford such progress? The Piper Unified School District project was funded through an energy services performance contract (ESPC), in which school districts receive energy infrastructure improvements with little or no up-front cost. Under an ESPC, an energy services company (like ConEdison Solutions) guarantees future energy savings to be generated by the improvements. That enables school districts to fund the costs of those improvements based on the savings.
 |
Photo: Honeywell
An energy audit is large in scope and specific to the site. |
Installed in the first phase of this energy-saving project: high-efficiency lighting, LED exit signs, occupancy sensors, an energy management system, rooftop units and upgrades, low-water flow fixtures, a voice-over Internet protocol phone system, a security system, and the football field turf and eight-lane track. The second phase included remodeling work related to the high school addition, such as energy-efficient lighting upgrades with drop ceilings, new HVAC systems, and water efficiency upgrades. Among environmental benefits, the project reduces 691 tons of greenhouse gas emissions annually, equivalent to preserving 4.4 acres of trees from deforestation or conserving 1,458 barrels of oil. That was surely an energy triumph for a Kansas City school district, and an education for us all.
Audits Vary in Scope and Quality
A huge shock for me occurred recently. I was chatting with the engineering and maintenance director for a local institution that has several buildings and many employees. I asked him if he has had an energy audit. Of course he had! A local lighting contractor had checked all their lights and told them how much they could save with new ones from his company. That was the institution’s energy audit. I have since discovered that this is not so rare, so I contacted the Association of Energy Engineers to get some words of wisdom (and consolation!).
“An energy audit can be simply defined as a process to evaluate where a building or plant uses energy, and identify opportunities to reduce consumption,” advises Albert Thumann, P.E., CEM. “Energy Audits can mean different things to different individuals. The scope of an energy audit, the complexity of calculations, and the level of economic evaluation are all issues that may be handled differently by each individual auditor and should be defined prior to beginning any audit activities.”
There is a direct relationship to the cost of the audit, how much data will be collected and analyzed, and the number of conservation opportunities identified. Thus, a first distinction is made between costs of the audit, which determines the type of audit to be performed. The second distinction is made between the types of facility. For example, a building audit may emphasize the building envelope, lighting, heating, and ventilation requirements. On the other hand, an audit of an industrial plant emphasizes the process requirements.
“Before starting the energy audit, it is helpful to have some idea of the scope of the project and level of effort necessary to meet expectations,” says Thumann. “There are three basic types or levels of energy audit, any of which may meet your requirements.”
The basic audit levels, in order of increasing complexity are:
Level I–The Walk-through Audit. The walk-through audit, as its name implies, is a tour of the facility to inspect visually each of the energy-using systems. It will typically include an evaluation of energy consumption data, to analyze energy use quantities and patterns as well as provide comparisons to industry averages or benchmarks for similar facilities. It is the least costly audit, but can yield a preliminary estimate of savings potential and provide a list of low-cost savings opportunities through improvements in operational and maintenance practices. The level one audit is also an opportunity to collect information for a more detailed audit later on if the preliminary savings potential appears to warrant an expanded scope of auditing activity.
Level II–Standard Audit. The standard audit goes on to quantify energy uses and losses through a more detailed review and analysis of equipment, systems, and operational characteristics. This analysis may also include some on-site measurement and testing to quantify energy use and efficiency of various systems. Standard energy engineering calculations are used to analyze efficiencies and calculate energy and costs savings based on improvements and changes to each system. The standard audit will also include an economic analysis of recommended conservation measures.
Level III–Computer Simulation. The level three audit will include more detail of energy use by function and a more comprehensive evaluation of energy use patterns. This is accomplished through use of computer simulation software. The auditor will develop a computer simulation of building systems that will account for weather and other variables and predict year-round energy use. The auditor’s goal is to build a base for comparison that is consistent with the actual energy consumption of the facility. After this baseline is built, the auditor will then make changes to improve efficiency of various systems and measure the effects compared to the baseline. This method also accounts for interactions between systems to help prevent overestimation of savings. Because of the time involved in collecting detailed equipment information, operational data, and setting up an accurate computer model, this is the most expensive level of energy audit but may be warranted if the facility or systems are more complex in nature.
Thumann says there’s another way of looking at levels of energy audits. This originated with Procedures for Commercial Buildings Energy Audits, 2005, ASHRAE, and is another excellent guideline for those wondering whether to audit or not, and how much to have audited by qualified auditors.
Level I–Basic
- Also known as the “one-day” or “walk-through” audit, this approach involves a cursory analysis of energy bills and a brief survey of the building to produce a rough estimate of how efficiently energy is used in the building.
- This level of effort will detect at least some of the “low-hanging fruit” and may suggest other options worthy of more study, but should never be viewed as comprehensive.
- Although this option is easiest, it also produces the crudest results.
Level II - Intermediate
- By investing more effort in the building survey and energy analysis, and by adding some system performance testing, this method provides a breakdown of how energy is used in the building as well as a broader range of savings options including simple capital investments.
- It accounts for the “people factor” and its effect on uncertainty of savings, and also explores maintenance procedures and assesses any impacts savings measures may have on them.
- Many facilities will find this level of analysis to be sufficient.
Level III – Advanced
- Also known as the “investment-grade audit”, this analysis digs into the details of any large capital projects you may be considering as a result of previous, simpler audits.
- Even more detailed data are gathered from field equipment. Extensive test measurements are taken which may include spot measurements and short-term energy monitoring. Possible risks are assessed, and intensive engineering and economic analysis produces reliable estimates of project energy and financial performance with the high confidence needed for major capital projects.
- These audit approaches tend to overlap in practice. All three assess the potential energy savings and initial cost of various energy savings strategies, so in that sense, all are similar. The differences are in your confidence that you’ve truly found all your savings opportunities, the accuracy of the expected savings and initial cost, and how much information you have about the difficulty of the project implementation and the likely persistence of the savings over time. The devil is definitely in the details.
- All level II and level III audits involve collecting general building data (location, size, usage type, energy sources), historical energy use data, and energy systems data (type of equipment in the envelope, lighting, HVAC, service water, etc.) to get a description of the facility. The more detailed the available data are, the more complete this description can be. For example, submetering within a building makes it easy to call out specific end uses or facility areas, and having daily or even hourly consumption data allows you to call out time patterns normally buried within the monthly billing cycle.
- All these data then feed an energy use analysis that lays out how much energy is consumed for each major end use in the building, such as space heating, space cooling, lighting, air distribution, etc. This defines a baseline scenario for future years, if no energy projects are undertaken. A similar analysis can be done with respect to peak energy demand.
- If you’re serious about saving as much energy cost as possible with the quickest payback time and least hassle, take the time to plan your energy projects right. Perform a good energy audit, and assess its results carefully based on the needs of your facility, whether based on annual savings, initial cost, payback time, synergistic comfort benefits to occupants, or recurring maintenance hassle. The rewards are well worth the work.
An absolutely essential element in all energy auditing is that the auditor be qualified to do the work, and not merely a vendor who has new, efficient products to sell for one aspect of your energy usage. The Association of Energy Engineers has developed a certification program for professionals practicing energy auditing: The Certified Energy Auditor (CEA) Program for Professional Certification. In 2006, the CEA and Certified Energy Auditor in Training certifications were developed and added to the impressive portfolio of certifications offered by the Association of Energy Engineers. Rising energy costs and inefficiency in plants and buildings is continually driving the need for trained and experienced energy auditors. The CEA certification is one that identifies professionals as having the required knowledge and experience needed to succeed in the growing field of energy auditing.
The objectives of the program are to raise the professional standards of those engaged in energy auditing, to improve the practice of energy auditors by encouraging energy auditing in a continuing education program of professional development, to identify persons with acceptable knowledge of the principles and practices of energy auditing through completing an examination and fulfilling prescribed standards of performance and conduct, and to award special recognition to those energy auditing professionals who have demonstrated a high level of competence and ethical fitness in energy auditing. (A useful reference would be the Handbook of Energy Audits, Eighth Edition by Al Thumann, P.E., CEM; William Younger, CEM and Terry Niehus, P.E., CEM, and published by the Fairmont Press.)
More Energy Management Successes
One small observation in my research into energy management has been that many of the successes have resulted from simple improvements. The change to motors with variable speeds may be the best example. That means that motors are not running full blast when nobody needs them. I was talking to some building engineers who had improved the efficiency of their sites by using (quite inexpensive) controls that allowed the cooling and heating in three conference rooms to be controlled depending on whether one, two, or three rooms were being used. Simple? Most effective, they said.
The Bank of America Plaza in Columbia, South Carolina, is a 17-story office complex with more than 300,000 square feet of Class A+ commercial office space. It opened in 1989, and in 2006 Cooper Realty Investments took ownership. Cooper challenged Johnson Controls to provide a solution for improving the performance and efficiency of the building, and bringing long-term savings where possible. Within six months, Johnson Controls proposed and initiated a retro-commissioning study to identify potential energy saving measures within the building. Over the next 18 months, Johnson Controls implemented a variety of approved conservation measures resulting in an annual utility cost savings of more than $43,000. Those measures included upgrading variable air volume controls from pneumatic to digital, installation of variable-speed drives on all cooling equipment, lighting control retrofits for the whole building, and upgrading the building controls to a Johnson Controls Metasys building management system.
Using standard Web browsers, the Metasys system communicates and maximizes monitoring and control of all the mechanical and electrical systems in the building. Control sequencing enhancements were accomplished. There, new controls on water heaters and unit heaters that allow off-hour scheduling and control sequencing to reduce energy consumption. The power monitoring initiatives included sub-metering of individual floors and select equipment. “In the past, our building’s HVAC and lights basically ran 24/7,” advises Amy Marthers, property manager at the Bank of America Plaza. “We are now able to better program equipment, based on when the building is actually in use. And we’re able to give tenants some control of their own space during off-hours, which they like.”
A keypad on each floor lets tenants override the preset schedule for HVAC and lighting. Because those billable hours can be tracked and reported, it helps Marthers and Cooper better manage energy costs and justify tenant charge-backs when appropriate. “These capabilities have a positive impact on leasing and tenant retention when our building is compared with others in the area,” observes Marthers. In March, 2010, the cooperative efforts of Cooper, NAI Avant, and Johnson Controls resulted in the Plaza being awarded LEED Gold certification, the first existing building in the state to achieve that honor.
Energy management and sustainability for buildings is not one of those flashes-in-the-pan that fizzle and go cold. The University of British Columbia (UBC) Centre for Interactive Research on Sustainability (CIRS) has been described as a living laboratory for researchers to teach, test, and study the long-term impact of sustainable practices and technologies. The center itself has advanced building controls, sensing technology, and management software from Honeywell. The research facility was built to LEED Platinum and Living Building Challenge certification standards.
“The University’s objective is to influence local, national, and global communities to become more sustainable,” notes Dr. John Robinson, executive director of the UBC Sustainability Initiative. “From the start, Honeywell and our other Strategic Alliance Partners were dedicated building a landmark research center that will impact the direction of eco-friendly products and strategies. The result exceeded our expectations and is a boon to UBC, and the companies and policymakers who have dedicated themselves to building a more sustainable future.”
For the CIRS, Honeywell installed heating and cooling, fire alarm, and security technology, and uses its Enterprise Building Integrator (EBI) to tie these and more than 80 third-party systems into a single interface that help the university operate the center more efficiently and cost effectively. “Research facilities like CIRS are not only going to change how buildings are constructed, controlled, and maintained, but they will produce the next generation of employees for Honeywell and the rest of our industry,” asserts Paul Orzeske, president of Honeywell Building Solutions.
Honeywell EBI is a facility management platform that reduces operating costs by integrating building technologies across a common IT backbone. It will manage the system, and aggregate and report performance data. Researchers will use these metrics to examine how people interact with the technology to optimize the use of energy and other resources. EBI will also help provide a comprehensive view and control of all operations (including lighting, utility metering, and rainwater collection). Honeywell will also help UBC display details on the building’s energy consumption and greenhouse gas emissions on the CIRS website, and a customized dashboard inside the center. Faculty and students in the facility can also access a Web portal to adjust temperature and lighting conditions in their individual offices and laboratories.
“It’s all happening here!” can be honestly claimed by many building owners and managers. Steadily, carefully, inexorably, we are improving the efficiency (and cost of operation) of our buildings. And they don’t have to be huge facilities with hundreds or thousands of employees. Simple improvements like variable speed motors can help even “normal” office buildings and commercial centers, improvements that have been identified as both appropriate and affordable in energy audits by qualified auditors. If there is one word that stands out, it is control. We can control the future efficiency of our properties, and the cost of controls can pay for itself in a surprisingly short time.
Author’s Bio: Paul Hull is a frequent contributor to Forester Media publications.
Advertisement]
|
|