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- Herausgeber: John Wiley & Sons
- Kategorie: Geisteswissenschaft
- Serie: Sustainable Design
- Sprache: Englisch
Practical solutions for sustainability In this timely guide, one of the world's leaders in advanced building technology implementation shows architects and engineers proven and practical methods for implementing these technologies in sustainably-designed buildings. Because of the very limited time architects are given from being awarded a project to concept design, this book offers clear and workable solutions for implementing solar energy, radiant heating and cooling floors, displacement ventilation, net zero, and more. It provides helpful tips and suggestions for architects and engineers to work together on implementing these technologies, along with many innovative possibilities for developing a truly integrated design. This book also explores and explains the many benefits of advanced technologies, including reduced greenhouse gas emissions, lower operating costs, noise reduction, improved indoor air quality, and more. In addition, Advanced Building Technologies for Sustainability: * Offers detailed coverage of solar energy systems, thermal energy storage, geothermal systems, high-performance envelopes, chilled beams, under-floor air distribution, displacement induction units, and much more * Provides case studies of projects using advanced technologies and demonstrates their implementation in a variety of contexts and building types * Covers the implementation of advanced technologies in office towers, large residential buildings, hospitals, schools, dormitories, theaters, colleges, and more Complete with a clear and insightful explanation of the requirements for and benefits of acquiring the U.S. Green Building Council's LEED certification, Advanced Building Technologies for Sustainability is an important resource for architects, engineers, developers, and contractors involved in sustainable projects using advanced technologies.
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CONTENTS
Introduction
Chapter 1: Sustainability and Energy
Quality of Life Benefits
Finite Fossil Fuel Resources
Greenhouse Gases
Profits and Savings from Energy Efficiency
Site-to-Source Effect
New LEED Version 2009
Per Capita Energy Consumption
Building Energy End-Use Splits, People Use Energy
Carbon Footprint
Funding Opportunities
Chapter 2: Radiant Cooling
History
Introduction
Why Radiant Cooling?
Applications
Radiant Cooling and Historic Preservation
Chapter 3: Displacement Ventilation
History
Introduction
Conventional or Mixed-Air Systems
Difference Between Displacement and Underfloor Air Distribution (UFAD)
Applications
Large Public Spaces (Cafeterias, Dining Halls, Exhibit Spaces)
Chapter 4: Chilled Beams
Principle of Operation and Technology
Benefits of Chilled Beams
Types of Chilled Beams
Chilled Beam Applications
Chilled Beam Use with Underfloor Air Distribution (UFAD) Applications
Chapter 5: Underfloor Air Distribution (UFAD)
Validation of UFAD Designs with CFD Analysis
Impact on Buildings
Chapter 6: Displacement Induction Units (DIU)
Benefits of Displacement Induction Units
History of Induction Units
Applications
Chapter 7: High-Performance Envelope
Engaging and Nonengaging Envelopes
High-Performance Envelope Definition
Most Common Energy Codes: ANSI and ASHRAE 90.1
Glazing Characteristics
How to Exceed the Mandatory Code Performance
Chapter 8: Thermal Energy Storage
Renewable Energy Storage
Conventional Air Conditioning Systems
Nonrenewable Energy Storage
Chapter 9: Solar Energy and Net-Zero Buildings
Net-Zero Step 1: Harvesting Solar Energy
Solar Energy in Net-Zero Buildings
Net-Zero Step 2: Improve Energy Efficiency of the Building and Its Mechanical and Electrical Systems
Net-Zero Step 3: Reduce Consumption
Chapter 10: Geothermal Systems
Introduction
Geothermal Heat Pumps
Types of Heat Pumps
Chapter 11: Cogeneration
Other Applications of Cogeneration
Cogeneration Technologies
Micro-Cogeneration or Combined Heat and Power (Micro-CHP)
Chapter 12: Data Center Sustainability
History of Data Centers
2011: Top Ten Trends in Data Centers
Power Usage Effectiveness (PUE)
Technologies That Can Benefit Data Center Efficiency
Office Building Applications
Air Management in the Data Center
Index
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Copyright © 2012 by John Wiley & Sons, Inc. All rights reserved
Published by John Wiley & Sons, Inc., Hoboken, New Jersey
Published simultaneously in Canada
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Library of Congress Cataloging-in-Publication Data:
Syed, Asif.
Advanced building technologies for sustainability / Asif Syed.
p. cm.
Includes index.
ISBN 978-0-470-54603-1 (cloth); 978-1-118-24121-9 (ebk); 978-1-118-24127-1 (ebk); 978-1-118-25973-3 (ebk); 978-1-118-25980-1 (ebk); 978-1-118-26019-7 (ebk)
1. Sustainable buildings. 2. Sustainable design. 3. Building—Technological innovations. I. Title.
TH880.S94 2012
720’.47—dc23
2011036328
This book is dedicated to my father, S. A. Sattar.
ACKNOWLEDGMENTS
Thank you to my family, Miraj, Azhad, and Rabia for your understanding, support, and patience.
Thank you to my mentors and supporters, M. M. Mohiuddin, Erv Bales, Thomas Gilligo, Marc Lorusso, Peter Flack, Norman Kurtz, Alan Zlotkowski, Lenny Koven, and Paul Bello.
Thank you to my editors, Kathryn M. Bourgoine, Doug Salvemini, and Danielle Giordano.
INTRODUCTION
IT HAS BEEN A HUMBLING EXPERIENCE for me to be part of several high-profile projects in the United States and internationally. Most of these projects had some form of a different approach than conventional systems and almost all of them involved integration between different disciplines of the building design. After completing the projects, some of which were very high profile and received a lot of media publicity, I was approached by building industry professional organizations to speak about the projects. When I did so, it came as a big surprise to me that most people in the industry were not familiar with the new and advanced technologies available. Most people who attended these simple lectures were very curious. The most common question was how they could implement these technologies in their projects. Though most of the technologies were basic, they were different from the conventional industry standards. I saw a great desire in all sectors of the building industry to learn these new and advanced approaches and technologies and implement them in their projects. The problem I saw was that different sectors of the building industry required different levels of information or details about these technologies. It was important for architects to integrate these new and advanced technologies into buildings. The contractors were interested in the availability of materials and products, and in how much they cost, compared to the conventional approach. The owners, building developers, and users wanted to make sure the technologies worked and that the associated costs were justified. A common question: Was the pay back sufficient to offset the savings in energy? The engineers were concerned about the liabilities of trying out new systems and were curious about how to perform the calculations, which they had not been taught, and which were not available in most books or software. To a great degree, I saw that most of the building professionals acknowledged the benefits.
The challenge and opportunity I faced was to write a book that would be beneficial to all sectors of the building industry. The information it contained must not overwhelm any one sector or be too little for another who wants to implement these technologies in their projects. I have tried my best to reach an optimum balance of information, neither too much nor too little. Drawing on my thirty years of experience of working with contractors, construction managers, project managers, owners, architects, end users, and equipment vendors, I have tried to do my best to balance out the information. The other challenge I had was to get this information out as soon as possible. With the ever-increasing demand for sustainability and energy efficiency, time was not there. Almost all projects have some form of sustainability element such as LEED certification, energy use reduction, high-efficiency products, high-performance buildings, and so forth. AIA’s adoption of the 2030 goal to make building carbon neutral by 2030 demonstrates the urgency for the need of this information.
Here’s how it all started: There was—and now is, more than ever—a need in the building industry to reduce energy consumption. This need is driven by several factors, such as sustainability, reduction in operating costs, and the desire to obtain LEED certification. This situation drives the building industry to new challenges to beat the benchmark. The conventional systems in the building industry, especially in the HVAC sector, are so common that they have become the benchmark for measurement of energy, as established by several codes and standards. Any technology that exceeds the benchmark in reducing energy can be considered as advanced and improved. This standard, which establishes that the minimum performance for energy is ASHRAE 90.1, is used by most states in the United States, and by the United States Green Building Council for LEED certification of buildings, and internationally by several countries. Sustainable buildings aspire to reduce energy by 15 to 60 percent more than required by this benchmark. Fifteen percent better than Standard 90.1 is the minimalist approach, prescribed by the USGBC for LEED certification, and can be achieved with relative ease. Sixty percent better than Standard 90.1 is challenging, but can be achieved by incorporating some of the technologies in this book.
The usual systems are so entrenched in the conventional way of doing business that any change is difficult. The entire building industry—the users, architects, engineers, owners, contractors, product manufacturers, and so forth—is so used to working with conventional systems that a change throws them off and can cause difficulties for all. In order to eliminate these difficulties, a new approach—integrated design—is recommended. This new approach of integrated design is holistic and interconnected; it combines the synergies of all parties. It brings together all parties and stakeholders involved from the beginning of the project. This facilitates buy-in by all parties and eliminates surprises. The bigger challenge to new technologies or solutions is less in technical aspects than in the process, because of the technologies’ unknown nature. The unknowns, when discussed up front, will educate and inform all parties involved in the project and make the process easier for all concerned. This can significantly reduce the cost of building. Generally, there is an increase in the cost of anything that is new and not familiar, even if it is much simpler and/or uses fewer materials to build than the conventional method. An integrated approach is strongly recommended for projects where new technologies are to be implemented.
Over the last few years, there has been significant publicity, in the media of the building industry and in the general media, highlighting the need for sustainable and energy-efficient buildings—but a lot still has to be done. Buildings are essential to the life and work of all human beings and benefit us in enormous ways. The environmental impact of buildings has become a significant factor in their design and construction. As per data published by United States Environmental Protection Agency, buildings in the United States use about 40 percent of the total energy produced, consume 68 percent of the total electricity produced, and account for about 38 percent of carbon emissions. The environmental impact of buildings is significant, and any steps taken to reduce their energy and electricity consumption have the dual advantage of both environmental and economic benefits. Any energy or electricity not consumed is money not spent on fuel. Reduction in the operating costs from consuming less energy can only benefit the competitiveness of the business in the global market. This book gives examples of projects that have implemented the new technologies to reduce energy consumption and contribute to the sustainability goals of the buildings.
The sustainable technologies can be evaluated based on their own merits of return on investment and life-cycle costs. Most building systems have a long operating life. In older buildings, systems installed as far back as forty years are still operating. The new energy saving technologies will also have a similar life cycle. The long building life cycle leads to the high rate of return on investment. The payback on advanced technologies can vary from as low as two to as long as twenty years. A yearly cash flow analysis for the life cycle is the best way to demonstrate the rate of return on the investment. Most sustainable technologies support a rate of return due to their long-term use over fifteen to twenty years. Readers are encouraged to investigate these and understand the financial issues prior to working with the technologies. The financial return on investment analysis is the best tool to convince the critics of sustainability.
The technologies are constantly evolving with innovations in construction products and materials, lessons learned from operating, new system designs, and construction means and methods. The technologies in the book are not the end of the line toward sustainability, but only a beginning. Our experience and information gathered will make these systems better and more efficient. These technologies are the first ones to replace the conventional systems. As they get more widespread the costs will reduce and improvements will be made, making them more efficient.
CHAPTER 1
Sustainability and Energy
BUILDING ENERGY CONSUMPTION IS A SIGNIFICANT PORTION of the total energy used worldwide. In the United States, buildings use about 40 percent of the total energy consumed and about 68 percent of the electricity produced. Buildings are responsible for 38 percent of carbon emissions.1 Buildings account for the highest carbon emissions, followed by transportation and industry. Buildings will continue to grow as the population of the world grows. The current world population according to the U.S. Census Bureau is 6.9 billion2, and is projected to grow from 6.1 billion in 2000 to 8.9 billion in 2015.3 The growth in population creates demand for new buildings: residential, educational, commercial (office and retail), health-care, and manufacturing. Growth of the buildings is going to happen, whether we like it or not. These new buildings will increase the demand for energy, increasing the cost of energy. Additionally, the growth of buildings will increase the global carbon emissions.
Figure 1-1 Building energy use according to the U.S. Department of Energy.
Buildings Energy Data Book
Economic development is essential to the social, political, and economic order of the world, and building construction is a big part of the economic development of all the world’s countries. With almost 9 million people employed in construction (per 2008 statistics), it is one of the largest industries. The wages of construction workers are relatively high. The construction industry also creates and promotes small business, as more than 68 percent of construction-related establishments consist of fewer than five people, and a large number of workers in construction are self-employed.4 Economic development and growth will continue to add new buildings. The new buildings present an opportunity to adopt new technologies and reduce the increase in demand for energy, thus containing the cost of energy. Slowing down the increase in energy consumption through advanced technologies also reduces carbon emissions, reducing the impact of development on the environment.
In the 1300s, Arab historian Ibn Khaldun defined or described economic growth as:
When civilization or population increases, the available labor or manpower increases. In turn, luxury increases in correspondence with the increasing profit, and the customs and needs of luxury increase. Crafts are created to obtain luxury products. The value realized from them increases, and, as a result, profits are again multiplied. And so it goes with the second and third increase. All the additional labor serves luxury and wealth, in contrast to the original labor that served the necessity of life.
Versions or parts of Ibn Khaldun’s theory are still valid in modern times, which means that economic development is imminent and ongoing. Construction of new buildings is a big part of economic development and will continue, as a result of:
Growth due to increase in population
Higher rate of growth in the developing countries due to globalization
A very high disparity between the per capita energy consumption and building footprint in developing countries vs. developed countries
Trying to catch up with developing countries puts additional demand above and beyond normal population growth.
New technologies can contribute to slowing down the growth of energy consumption, without slowing down the economic growth that is essential to maintain the world’s social, political, and economic order. The goal of energy savings in buildings is to reduce the rate of growth of energy consumption, while maintaining economic growth. World economic growth is expected to grow 49 percent by 2035, as reported by the United States Energy Information Administration report International Energy Outlook 2010.5
Continuing at this rate of growth and development with the current practices of using energy, which primarily comes from using fossil fuels, has two diametrically opposite forces. On one side is growing more, traveling more, having more space, and brighter and bigger cities. On the other side, there are limited or declining resources. Effectively utilizing resources is essential or soon it will take more than one earth to meet the growing needs for resources. “Soon” is now, according to the Global Footprint Network, an alliance of scientists who calculate that in 10 months, humanity will have exhausted nature’s yearly budget.6
Figure 1-2 World marketed energy consumption in three economic growth cases, 1990–2035.
U.S. Energy Information Administration
Figure 1-3 Shares of world energy consumption in the United States, China, and India, 1990–2035.
U.S. Energy Information Administration
Growth in the developing countries will occur at a much higher rate than in the developed Western world. The U.S. Energy Information Administration has made two forecasts: high economic growth (63%) and low economic growth (37%). With higher growth rates in the developing world or the newly industrialized countries, the median growth of 50 percent is very likely, based on the growth rate and energy consumption growth of India and China. To a certain degree, India’s and China’s energy consumption growth will not put all the pressure on fossil fuels, given their high level of growth in nuclear power plants. According to the World Nuclear Association,7 nuclear power generation has the highest growth in Asia. China, Japan, South Korea, and India are the countries with the largest number of nuclear power plants planned; more than eighty-four nuclear power plants are planned in these countries. The recent tsunami in Japan has exposed the vulnerability of nuclear power generation. The damages from the tsunami are evident, and several countries are reevaluating their dependence on nuclear power. Every country is evaluating whether the benefits are worth the risks. It is too soon to predict (1) the pressures that the increase in demand for energy will put on the prices of clean-burning fossil fuels or (2) the huge environmental impact of growth in conventional coal power plants.
The worldwide economic growth will put intense pressure on energy resources and will increase the demand for energy and fossil fuels. In the current methodology of energy production, energy and fossil fuels are almost synonymous, as currently fossil fuel is the major source of energy. Fossil fuels such as oil, coal, and natural gas account for more than 85 percent of the energy used in the United States.8 The same fossil fuels produce about 70 percent of the electricity. The other 30 percent breaks down as 20 percent from nuclear power plants, 6 percent from hydro power plants, and 4 percent from renewables such as solar and wind power.9 Making improvements to buildings’ energy use and efficiency can generate significant savings in energy and fossil fuel costs. The majority of fossil fuels are a globally fluid commodity that flows to the place of demand or to the highest bidder. The fluidity of the fuel creates a global demand. The increase in demand is much higher in the developing countries.
Potential opportunities exist to make improvements to buildings in the mechanical, electrical, and plumbing (MEP) systems to improve their energy efficiency. There are currently available technologies that are cost effective and can reduce energy consumption by a significant amount. According to guidelines published by the American National Standards Institute (ANSI), the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), and the Illuminating Engineering Society of North America (IESNA), almost 50 percent of energy can be reduced in office buildings.10 The most common standard used the world over, and adopted by most states in the United States is the ANSI/ASHRAE/IESNA Standard 90.1. The same professional organizations that wrote Standard 90.1 have also written design guides on how to achieve up to 50 percent energy savings over their own standards. Clearly, from these publications, there is evidence that there is significant opportunity to reduce energy in buildings. According to the United States Green Building Council (USGBC), a nonprofit organization that promotes sustainability in the building industry, there are potential technologies for existing and new buildings that can reduce energy use by 25 percent and carbon emissions by 30 percent.11 Moreover, there are opportunities to continue with growth and its economic benefits, but reduce the impact on energy resources, fossil fuels, and the environment by adopting the efficient technologies.
However, these technologies are not commonly known to the construction industry, including most design professionals, contractors, and manufacturers of building construction equipment and materials. Most of these new and advanced technologies or design approaches are basic and simple in nature, and easily understandable and implementable. However, they are different from the current popular practices employed by the building design industry, including design professionals, contractors, and building operators. There are a select few professionals, both architects and engineers, who are familiar with and can confidently design these new technologies or mechanical or electrical systems; however, for the majority of the construction industry, these are technologies they have only heard about or read about. The “unknown technology factor” is the biggest barrier to the use of the more efficient and advanced technologies. To a certain degree, the problem is also the need to break an old habit or to change “business as usual.” To successfully implement the new and advanced solutions, there has to be a change in attitude, approach, and practice in the profession. This change is very difficult to bring about in a well-established industry such as the building construction industry, which is a major contributor to the overall economic activity of the United States and the rest of the world. Construction totals to about $800 billion a month, resulting in approximately $9 trillion per year.12 The construction industry is one of the largest and is well set in its systems, practices, methods, and approach. Even a small change in this industry is difficult and takes a long time. However, there are positive trends; many projects that have incorporated advanced sustainable technologies are featured in the press and have received positive publicity with their success. Professional organizations such as the American Institute of Architects (AIA) and ASHRAE are promoting these technologies. Government bodies such as the Department of Energy (DOE) are promoting energy efficiency with several programs such as Portfolio Manager, whereby buildings are ranked by their energy consumption compared to similar buildings. Only five to six years back, the universal answer of builders and designers to the question, “Does it cost more to adopt sustainable technologies?” was, “Yes.” Now, many builders and designers—if not all—can confidently say, “It does not cost more to employ sustainable technologies.” This is a significant shift in position over the last five years. Also, most building owners have voluntarily adopted sustainable technologies to reduce energy use or to be green. Most building owners are designing and operating buildings to USGBC, to obtain LEED certification.
The cost of these new or advanced technologies is not necessarily higher than that of the conventional systems. However, it depends on whom you ask. Professionals who are familiar with the advanced systems will agree that the construction cost is the same, and that if there is an additional cost, it usually is recouped within a reasonable payback period. Professionals who are unfamiliar with these systems will generally believe that advanced technologies cost more, primarily because the “unknown technology factor” raises the cost far higher than the true cost. Some of these technologies do not cost more than conventional systems; they are simply different. Some may cost more for one item, but reduce costs for other items. For example, in underfloor air conditioning systems, the cost of the raised floor is higher, but there is no need to install ductwork and associated accessories such as variable air volume (VAV) boxes and the like. If there are any additional costs, usually they have a very short payback period. The increase in the cost is offset by the energy savings. The payback is calculated with energy analysis and life-cycle cost analysis. Life-cycle cost analysis has not been part of the construction industry; most design professionals are unfamiliar with it. Thus, these professionals are not able to calculate the necessary life-cycle cost or yearly operating cost to demonstrate how payback will justify the expense. Lack of knowledge of or familiarity with new and advanced technologies is limiting. Most in the construction industry tend to stay with what they know and have experience with. This book will demonstrate that the new technologies are basically energy efficient, sound, simple, easy to build, user- and operator-friendly, and cost effective. It will be a small step toward making the entire construction industry familiar with new and different solutions, which will eventually remove the fear of the unknown. This knowledge and awareness in the building construction and operations industry will transform the way buildings are designed, built, and operated.
QUALITY OF LIFE BENEFITS
In addition to their energy and environmental benefits, new technologies improve the quality of life for a building’s occupants. Indoor air quality is one of the major factors that affect the quality of life in buildings. People spend 90 percent of their time inside buildings, making it all the more important to focus on the quality of life a building provides for its occupants. Sick building syndrome (SBS) explains why those who spend a lot of time in a building complain of ill health and discomfort, with no apparent cause. The causes of sick building syndrome are generally:
Advanced systems, in addition to reducing energy use, have better indoor air quality than conventional systems, leading to better health for the occupants. Indoor air quality is just as important as outdoor air pollution—and in some instances more important. Since people spend 90 percent of their time in buildings, indoor air quality is an important factor in their well-being. Most of the conventional systems that are predominant in the building industry do not improve indoor air quality, and in most instances are detrimental to it. The EPA recommends three basic strategies for improving indoor air quality:13
Two out of the three recommendations are systems-related. Improved ventilation can be achieved by increasing the percent of outside air that is circulating in the building. Only from 15 to 20 percent of the total air circulating in a typical building is outdoor air; 85 percent is recirculating air. LEED certification recognizes this, and in their point-based rating system, the USGBC provides means of increasing ventilation and achieving additional points. However, while implementing this process, careful analysis has to be made to evaluate the outdoor air quality level. Some areas in the country, especially urban environments, have high levels of outdoor contaminants. Another common way to improve ventilation is by providing operable windows, enabling building occupants to decide the need for more outside air. Improved ventilation may not necessarily result from an increase in outside air, but from the effectiveness with which the outdoor air is delivered to occupants. The conventional systems really fall short in delivering outside air to occupants effectively. The standard overhead air distribution systems mix pollutants in the air delivered to a space, increasing the parts per million (PPM) of contaminant particles at the occupant breathing elevation. Advanced systems such as underfloor air distribution (UFAD) systems reduce the PPM of contaminant particles.
The most effective way to keep the indoor building environment or air clean is to control the source. The source of the contaminants can be indoors or outdoors. Inside source control is accomplished relatively easily by properly selecting the materials and furnishings that make up the indoor environment. Huge strides have been made in this sector, and most indoor materials are rated or labeled with their potential emission of contaminants. Increasing the outdoor air percentage is another way to control indoor source pollution, as the outside air will dilute the contaminants. Increasing the outdoor air percentage of the circulating air has some limitations, however. Depending on the location of the building, the outdoor environment may be too hot or too cold, requiring excessive energy to heat or cool the outside air. Some regions may have harmful levels of outdoor contaminants, limiting the amount of outside air use. Therefore, a good air-cleaning system is essential. Improvement of the efficiency with which the air-cleaning system captures the contaminants from the circulating air is essential in both conventional and advanced systems. LEED building-rating systems recommend a minimum efficiency reporting value of 13, or MERV −13, for permanently installed mechanically ventilated systems, for circulating both building air and outside air. An air-cleaning system can be detrimental to the overall system, however, because a fine filter or air cleaner requires additional energy. Indoor air quality control is a balance of several variables that include: indoor contaminants, outdoor contaminants, ventilation effectiveness, the outdoor environment, filtration, and the delivery system.
FINITE FOSSIL FUEL RESOURCES
Most of the energy we produce and consume comes from finite resources. About 56 percent of the energy produced in the United States comes from finite resources such as coal (22%), natural gas (21%), crude oil (11%), and natural gas liquids (3%). All the resources are finite and will not last forever. Even coal, the largest energy reserve, is a finite resource.14 The very definition of sustainability, “endure without giving way or yielding,” conflicts with the use of finite resources such as fossil fuels, which will run out eventually. Until alternate nonyielding resources are tapped into, or technologies are developed to fully utilize renewable resources, it is essential to reduce energy consumption by buildings. A 30 to 50 percent reduction in the energy consumption of buildings can lead to a 12 to 20 percent reduction in overall energy use. The ultimate goal is to have all energy come from renewable sources such as wind, geothermal, and solar power. But this will not come about in the immediate or near future. The current focus is on reducing energy consumption by improving the efficiency of building systems, which will accelerate the ultimate goal of relying exclusively on renewable energy.
Figure 1-4 U.S. Primary Energy Production by Major Source (2009).
U.S Energy Information Administration, Annual Energy Review, 2009, Table 1.2 (August 2010)
Figure 1-5 U.S. Coal Resources and Reserves (Billion short tons as of January 1, 2010).
U.S. Energy Information Administration, Form EIA-7A, Coal Production Report (February 2011)
GREENHOUSE GASES
Gases that trap heat from the sun are called greenhouse gases. These gases are essential to life on the Earth in its current form. It is the greenhouse gases that maintain the temperature on the Earth that sustains life. In the absence of the greenhouse gas effect, the temperature of the Earth would be lower by 60°F.
There are several greenhouse gases—the six identified by the U.S. Energy Information Administration and the Kyoto Protocol are:
Figure 1-6 Greenhouse gas effect.
Asif Syed
Figure 1-7 Aggregate Contributions of Major GHG Emitting Countries.
U.S. Energy Information Administration
When sunlight strikes the Earth, some of the energy is re-radiated back into space as infrared energy. All greenhouse gases absorb this re-radiated energy as infrared radiation (heat). The absorbed energy of the greenhouse gases causes heat to be trapped in the atmosphere. Burning fossil fuels leads to the production of carbon dioxide (also referred to as CO2) emissions. Of the listed greenhouse gases, carbon dioxide is the largest contributor to the greenhouse gas effect. Advanced systems reduce the consumption or burning of fossil fuel for energy, thus reducing the production of carbon dioxide. This leads to the reduction of greenhouse gases.
PROFITS AND SAVINGS FROM ENERGY EFFICIENCY
Energy savings have a direct impact on the bottom line of businesses and building owners. Energy saved through conservation measures and efficiency is energy not consumed. The unconsumed or saved energy does not have to be paid for. The savings from energy efficiency are not commonly discussed. Because of the low cost of energy in the past, compared to the overall or total cost of operating a building and business, the energy budget was small compared to the overall budget of business operation. The cost of energy was so small that it did not stand out or constitute an important factor. This is similar to the cost of gasoline for cars—it was not common to calculate the cost of gasoline while using a car. However, the state of the economy after 2007—with a recession second only to the Great Depression of the 1930s—has caused scrutiny on these aspects of business costs. The higher cost of energy prior to the recession and the apparent waste of energy have put the focus on energy savings and the costs associated with energy use. Savings from energy conservation and efficiency are directly related and proportional to energy saved and greenhouse gases reduced. This has been demonstrated at St. John’s University, in New York City, which saved $1,100,000 in operating costs while reducing greenhouse gases by 9,270 metric tons’ equivalents of carbon dioxide.15 St. John’s University has an energy efficiency improvement program and participates in the carbon footprint reduction program called the 3010 challenge. The 3010 challenge is for the educational institutions in New York City who voluntarily participate in the program, to reduce their carbon footprint by 30 percent in 10 years. The 3010 challenge is part of New York City Mayor Michael Bloomberg’s program to reduce the carbon footprint of New York City, called “Plan NYC.”
SITE-TO-SOURCE EFFECT
The amount of energy used in buildings as measured by electric utility meters, natural gas meters, or the measure of fuel oil delivered is not a true representation of the energy consumed by the building. The amount of energy generated at the power plant is much higher. This is especially significant for electricity and is about three times that used at site or in the building. For a 100 watt LED TV, about 300 watts of equivalent fossil fuels has to be burned in the power plant. Site energy is the amount of energy consumption reflected in the utility bills, but it is not the true representation of energy use. The primary form of energy bought at the building site, such as natural gas, comes from a distant location, and losses are associated with it. The most common form of energy used in buildings is electricity, which is considered a secondary form. Electricity is produced by burning a fossil fuel or by a hydro or nuclear power plant, but the most common form of fuel for electricity is fossil fuel. The secondary form of energy electricity is produced in a power plant. Most thermal power plants have only about 30 percent efficiency. So the energy equivalency is much larger at source than at site. In the case of electricity—the most common form of energy—the site energy equivalency is about 3.34.16 The site-to-source factor includes the thermal efficiency losses and transmission losses. For the most common energy uses, the EPA methodology for calculating site-to-source conversion factors is as follows:
TABLE 1-1 Site-to-Source Conversion Table
#
Fuel Type
Site-to-Source Ratio
1
Electricity (grid purchased)
3.34
2
Electricity produced on-site from solar or wind
1.0
3
Natural gas
1.047
4
Fuel oil
1.01
Generation of electricity with fossil fuels is a very inefficient process, with losses as high as 60 to 70 percent. The losses are in the form of heat in the flue gases of the combustion, which are vented into the atmosphere. The heat from the flue gases is not useful in most locations of the power plants, which leads to lower efficiency. Site-to-source conversion is especially important because any reduction in energy at site is almost three times the energy saved at the power plant. The reduction in the greenhouse gases is also three times the amount of energy saved.
NEW LEED VERSION 2009
The new LEED rating system has increased the emphasis on energy. When United States Green Building Council’s LEED rating system started, certification—or higher levels such as silver or gold—did not require mandatory points in the energy and atmosphere category. However, in 2007, for basic certification or higher ratings, the emphasis on energy increased, and it became mandatory to obtain two points in energy and atmosphere. Two points meant 14 percent better than the energy code minimum. This has forced architects and engineers to come up with innovative designs. The standard used for energy code minimum is almost universally the American Society of Heating Refrigeration and Air Conditioning Engineers ASHRAE 90.1. The ASHRAE 90.1 standard is becoming more and more efficient as newer versions are introduced every three years. Achieving lower than baseline minimum code was much easier in the past, but with newer versions it is more challenging. Some or most of the advanced technologies are still not the minimum or baseline code requirements, presenting an opportunity to exceed mandated energy efficiency and add more points toward LEED certification.
USGBC’s LEED certification process is continuously increasing its emphasis on energy. In the earlier versions of certification, the only energy prerequisite was to comply with code. Additional energy use reduction was optional. Later, in 2007, a mandatory rating of 14.5 percent better than the code became a prerequisite for certification. The LEED 2009 rating system has increased the importance of energy by increasing the points for energy credits. LEED 2009 has 19 points in a 100-point system, with an almost 20 percent emphasis on energy. To achieve higher ratings such as gold and platinum, advanced systems can be used to maximize the points.
TABLE 1-2 LEED Rating Systems Energy Optimization Points
LEED Rating Version for New Construction
LEED Energy/Total Points
% of Total Points
LEED 2
10/69
14.5%
LEED 2.1
10/69
14.5%
LEED 2.2 (before July 2007)
10/69
14.5%
LEED 2.2 (after July 2007)
10/69 – 2 mandatory
14.5% (2.8% mandatory)
LEED 2009
19/110
18.2%
PER CAPITA ENERGY CONSUMPTION
The per capita energy consumption of all countries indicates that there is a big gap between the developed countries and the developing countries. The average power consumption17 of developed countries is 200 MBtu, whereas in the developing countries it is about 20 MBtu. The developing countries have populations that are much larger than those of the developed countries. With the total population of the world at 7 billion, 6 billion people live in the developing world, and only 1 billion in the developed countries.18 The huge populations of developing countries aspire to the quality of life and the lifestyles of the developed countries. If the populations of developing countries start consuming the same 200 MBtu, the consumption of energy will not be sustainable. Sustainable technologies can help in lowering energy consumption in the developing world. However, most developing countries are using systems that were used in the developed world in the 1970s and 1980s. The technologies of 1970 and 1980 were not energy efficient. Generally, the developing countries emulate what is being done in the developed world. This cycle has to be broken, and new and advanced technologies have to be adopted in the developing world, alongside the developed world, to make a difference in the overall energy consumption of the world.
Figure 1-8 Per capita energy consumption of representative countries of the world.
U.S. Energy Information Administration
BUILDING ENERGY END-USE SPLITS, PEOPLE USE ENERGY
The data collected19 by the U.S. Department of Energy indicates that almost 50 percent of the energy consumed by buildings goes into serving the occupants’ needs, such as water heating (9.6%), electronics (7.6%), refrigeration (5.5%), cooking (3.4%), computers (2.3%), and so on, and that the remaining 50 percent goes into space lighting, heating, and cooling. People use energy whether they are in large commercial buildings, at home, or elsewhere. The space heating, which is 20 percent, provides protection from the elements and is a necessity, whether people are in structured commercial buildings or just at home. Space cooling provides comfort; it was originally considered a luxury, but it has become a universal necessity, and most homes are now air-conditioned.
People consume energy, and building systems are a means of delivering the energy. Reducing energy in buildings is a twofold issue: occupants and systems. The ratio of influence of the people and the system is an equal fifty-fifty split. Actions or behaviors of the building users and occupants can make a significant difference in the overall energy consumption. An integrated design approach of advanced systems engages the occupants and brings about the awareness of the entire building design process and the importance of energy and sustainability. Occupants learn how their behavior has an impact on the building’s energy and sustainability. This will lead to change in behavior, which will be a benefit.
In the present building design process, the art and science of occupant behavior impact on energy does not exist. Occupant behavior is not considered as a design issue. Integrated design and engaging advanced technologies is a starting point, but soon a new chapter has to be written on this subject. In net-zero buildings, especially the ones when energy is produced on-site with solar photo voltaic cells, occupants understand this. The behavior of occupants can reduce energy, which does not have to be produced in a photo voltaic panel, leading to lowering the capital cost. The initial capital investment associated with solar photo voltaic panels can have an influence on the behavior aspects of the occupants. Some examples of behavior can be using natural light and ventilation.
The efficiency level associated with the systems that deliver the energy to the occupants can be improved with the assistance of the advanced technologies now available. For example: Fans commonly used in buildings are only 65 percent efficient, and air used to transport cooling has extremely low heat-carrying capacity, or specific heat. On the other hand, pumps are 85 percent efficient, and water has very high heat-carrying capacity. Selection of a water-based system can significantly lower the energy consumed. Harvesting daylight by appropriately selecting glazing and lighting control systems, such as dimming, can reduce the lighting energy consumption, which is a significant split. Technologies for glazing include spectrally selective coatings that reduce solar heat gain and maximize light transmission.
Figure 1-9 U.S. Buildings Energy End-Use Splits.
U.S. Energy Information Administration
CARBON FOOTPRINT
Most organizations, in both the public and private sectors, are becoming carbon footprint conscious. Carbon Disclosure Rating (CDR) is a numerical score based on the level of reporting of a company’s climate change initiatives. This is in response to the questionnaire that was developed by the U.K.- based Climate Disclosure Project (CDP) along with PricewaterhouseCoopers. The score is not indicative of the actions taken by the company to mitigate it’s climate change issues. The score only indicates the level of disclosure of a company’s climate change issues. A high score generally indicates a good understanding and management of issues that impact the climate from a company’s activities. Most large companies have a Carbon Disclosure Rating. Carbon disclosure ratings are given for stocks’ symbols along with the companies’ profit margins, P/E ratios, and return on assets. Companies that are tracking their carbon footprint and their climate change impacting issues need to equip their building systems with advanced technologies that use less energy and thereby leave a lower footprint reducing their impact on climate change. The carbon footprint is a measure of the release of all the six gases identified by the Kyoto Protocol as greenhouse gases: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6
