ConstructionPro Week, Volume: Construction Advisor Today - Issue: 16 - 08/13/2009

Commercial Energy Audits, Part 2

 Commercial energy audits can provide an owner, building contractor or management company a solid blueprint of how efficiently energy is used in the building, point out savings options, as well as outline future areas for improvement through energy retrofits. Common energy loss problems can be identified by using a basic walk-through audit. More in-depth audits, with follow-up retrofitting, can lead to even greater energy savings.

A Building's Problem Areas
Typical energy loss problems in commercial buildings are found in three areas: the building envelope, HVAC and the electrical system. "Loss problems [in the building envelope] occur by way of infiltration, conduction and radiation," said Jerry Jackson, industry solutions manager for energy and sustainability at Autodesk.

Poor joint sealings are most often the culprit of unwanted air infiltration. "In essence, it can really be considered additional ventilation," Jackson said. "Conduction happens where a temperature gradient exist on, for instance, either side of a wall. Heat flows from the warm side to the cool side, and commonly, insulation is prescribed to resist such heat flow.  Radiation is the transfer of radiant (sun) energy, which is absorbed by the envelope walls, roofs, etc."

 


HVAC processes can account for roughly 40 percent of the energy used in a building; therefore, it is critical that measures are taken to ensure efficiency. "Loss problems arise from inefficient mechanical units, such as air conditioners and heaters, set points of thermostats and constraints on proper flow of air through the ventilation system," Jackson explained.

 

The electrical system includes lighting, ballasts and building automation controls. "Loss problems take place due to inefficient lighting such as incandescent.  Or in some cases, the density of lighting is [higher] than required by the building," Jackson said.

 

For Johnson Controls, which manufactures auto parts, building efficiency systems and power solutions for a global market, "upgrading the lighting system can help the overall environment and reduce energy usage," said Darryll L. Fortune, the company's director of global public relations for building efficiency. "Johnson Controls experts also look at the utility rate structure to see if there is something operational that can be done to reduce the cost of the utility units," Fortune said.

 

Outdated equipment and equipment ill suited for a facility are the two most common problems Johnson Controls encounters during energy audits. "For example, organizations may have purchased equipment that at the time may have been considered energy efficient," Fortune explained. But over time, situations, operability, needs and equipment efficiencies change. That equipment may be required to perform in an environment and under different environmental conditions for which it is no longer suited, he said. For example, school population changes, factories adjust work hours to accommodate longer or shorter shifts, buildings are sold and partially retrofitted for different purposes. "The equipment may not be capable of adjusting to those conditions," Fortune said.

 

A Major Energy Drainer
Commercial buildings with data centers are also at risk for energy loss. A high availability data center can consume $20 million of electricity over its lifetime. Auditors typically look at just the facility's raw power and heating and cooling expenditures, said Erin Sanders of Acumen Solutions, a business and technology consulting firm based in Washington, D.C.

 

"For a high availability data center, an average of 33 percent of the total power is utilized by IT equipment," Sanders said. To properly audit a data center, you need auditors from two different backgrounds, she said -- one with a facilities perspective that can identify how to lower heat, cooling and power costs, and one with expertise in IT infrastructure and applications to uncover possible energy cost savings from clever or more efficient uses of technology and networking.

 

"Our experience has shown that many data centers operate far below their achievable efficiency. With more focus on the environment, many companies are beginning to track and/or control their carbon footprint," Sanders said.

 

A Network of Efficiency
It is important to note that none of these building components creates energy loss in isolation.  Nor can efficiency be created in isolation. "For example, a highly efficient building envelope can reduce the need for HVAC use. Lighting that produces less heat can help reduce energy consumption, and additionally, operable windows allow natural ventilation potential, reducing the need for air conditioning.  It is the interconnected relationship between the building, its systems and the environment in which it exists that creates complexity," Jackson said.

 

"It is this complexity to which software and the BIM approach is uniquely positioned," Johnson said. "[Building information modeling] enables designers, architects and engineers to accurately analyze and simulate the building, enabling opportunities for efficiency to be made transparent."

 

"With external environmental pressures, new technologies speed the work flow from many weeks to a few days, while expanding green job opportunities, adding operational efficiencies all the while bringing critical performance information earlier in the decision-making process so owners can make proper investment decisions, which help mitigate their risk," Jackson said.

 

"With a model-based approach that has BIM at the core ..., building owners, ESCOs, architects, engineers, energy analysts and contractors can take a pragmatic approach to assessing existing conditions and performing energy analysis early on in the design process to better the life of the building for today and tomorrow," he explained.

Global and Local Perspectives
Environmental legislation, regulations and incentives are increasingly becoming integral to the way the AEC industry does business. Though the United States trails behind Europe in energy efficiency initiatives, we are quickly catching up. And, other countries are joining the cause as well. For example, the Chinese government is increasingly mandating energy efficiency measures through legislative measures. Legislative measures are also in the works in France, the United Kingdom, Germany and Italy.

 

The U.S. House of Representatives has recently passed the American Clean Energy and Security Act (H.R. 2454), a controversial carbon cap and trade program. The bill is now under debate in the Senate. Proposals have also been made to cut greenhouse gas (GHG) emission to 20 percent below 2005 levels by 2020 and 80 percent reduction by 2050. And, plans are in the works to establish a renewable electricity standard reaching 25 percent by 2025.

 

In comparison, the European Parliament has passed the following legislation:

 

    * Zero emissions for all new buildings by 2019
    * GHG emissions cut to 20 percent below 1990 levels by 2020
    * Increase share of renewable energy to 20 percent by 2020
    * Improve energy efficiency by 20 percent 

 

In addition, the Carbon Reduction Commitment is the U.K.'s version of a cap and trade agreement that it hopes to enact. And, there is a push to enact an international climate treaty to replace the Kyoto Protocol by the end of 2009.

 

On a more local level, states are taking up the energy cause. Missouri, for example, gives a $1,000 tax credit to homeowners for professional energy audits and their associated energy-efficiency improvements (with a $2,000 cumulative cap). California, a frontrunner in sustainability issues, currently has the Skinner/Bass Bill (AB 758) working its way through the Senate Appropriations Committee. This bill would require the California Energy Commission to establish a regulatory process that requires existing residential and commercial buildings to implement programs to achieve greater energy savings.

 

Washington is joining the bandwagon, too. The state legislature approved Efficiency First, Bill SB5854. Among other things, this bill focuses on a strategic plan, energy codes and benchmarking that will require residential and commercial construction projects to achieve a 70 percent reduction in energy use. In addition, commercial and public buildings must maintain ongoing records of energy consumption data.

 

New York has established a State Energy Research and Development Authority, which provides energy audits to small businesses looking to make informed decisions about energy-efficiency strategies. This agency also helps customers obtain low-interest loans through the New York Energy Smart program.

 

Energy efficiency programs are gaining footing and popularity. The current assortment of incentives and legislation will only grow as more states develop their own plans to combat energy loss, reduce greenhouse gas emissions, lower state budgets, and plan for an energy-efficient future.

 

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