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Lean and Energy Assessment: Identifying Energy Savings in Lean Processes, Notas de estudo de Engenharia de Materiais

The benefits of integrating energy assessment strategies into lean processes. It provides examples of companies that have successfully reduced energy use and costs through lean initiatives, and outlines techniques for measuring energy use and identifying opportunities for savings. The document also highlights the importance of understanding the costs of energy use and the relationship between lean wastes and energy consumption.

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Antes de 2010

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Baixe Lean and Energy Assessment: Identifying Energy Savings in Lean Processes e outras Notas de estudo em PDF para Engenharia de Materiais, somente na Docsity! Achieving Process Excellence Using Less Energy The Lean and Energy Toolkit www.epa.gov/lean Toolkit Format and Icons The toolkit uses icons in the page margins to help you fi nd and follow important information in each chapter. Key Point Identifi es an important point to remember Key Term Defi nes an important term or concept New Tool Presents a technique or resource that helps capture, communicate, or apply new knowledge How-to Steps Describes sequenced actions to implement a tool Chapters also include one or more “To Consider” text boxes that contain questions to help you explore how the information relates to your organization. Lean and Energy Toolkit Table of Contents Executive Summary ...............................................................................................................................i Preface ...................................................................................................................................................iii Purpose of This Toolkit ....................................................................................................................iii Key Questions Addressed by This Toolkit ........................................................................................iii Chapter 1 Introduction ......................................................................................................................1 Benefi ts of Coordinating Lean and Energy Management ...............................................................1 Strategic Lean and Energy Management .........................................................................................5 Chapter 2 Overview of Energy Use and Lean ....................................................................................9 Energy Sources and End Uses ..........................................................................................................9 Understand the Costs of Energy Use ..............................................................................................12 Energy Effi ciency Benefi ts of Lean Implementation .....................................................................13 Chapter 3 Energy Assessment Strategies .........................................................................................15 A. Walk Through Processes to Observe Energy Use .......................................................................15 B. Energy Audits and Measuring Energy Use .................................................................................16 C. Examine Energy Use with Value Stream Mapping ....................................................................18 D. Use Six Sigma to Find and Eliminate Energy Waste and Variation ..........................................22 E. Conduct Energy Kaizen Events...................................................................................................22 Chapter 4 Energy Reduction Tools and Strategies ..........................................................................25 A. Use Total Productive Maintenance to Reduce Equipment Energy Waste .................................25 B. Replace Over-Sized and Ineffi cient Equipment with Right-Sized Equipment..........................28 C. Design Plant Layout to Improve Flow and Reduce Energy Use ................................................29 D. Encourage Energy Effi ciency with Standard Work, Visual Controls, and Mistake-Proofi ng ...30 Chapter 5 Conclusion .......................................................................................................................33 Lean Windows of Opportunity for Energy Savings ........................................................................33 Going Even Further with Clean Energy .........................................................................................34 The Lean and Energy Journey ........................................................................................................34 Appendices ...........................................................................................................................................37 Appendix A Energy Assessment Service Providers, Resources, and Tools .....................................37 Appendix B Sector-Focused Energy Reduction Resources .............................................................41 Appendix C Energy Conversion Resources and Rules of Thumb for Estimating Energy Cost Savings ..............................................................................................43 Lean and Energy Toolkit Boxes Benefi ts of Coordinating Lean & Energy Management (Box 1) .....................................................1 Lean and Energy Use Reduction: Company Cost Savings Experience (Box 2) ...............................3 Lean and Energy at Toyota (Box 3) .................................................................................................4 Why Be Strategic about Energy Management? (Box 4) ...................................................................5 Energy End Uses: What Do We Use Energy to Do? (Box 5) ...........................................................10 Questions for Understanding Energy Use (Box 6) .........................................................................15 Energy Treasure Hunts at General Electric (Box 7) ......................................................................16 Energy Savings From “Lean and Clean” Assessments (Box 8) .....................................................17 Common Energy Units (Box 9) ......................................................................................................17 Example Results from Value and Energy Stream Mapping Projects (Box 10) .............................19 Six Sigma and Energy Savings at Baxter International (Box 11).................................................22 What is an Energy Kaizen Event? (Box 12) ...................................................................................23 What is TPM? (Box 13) ...................................................................................................................25 Four Strategies for Integrating Energy-Reduction Efforts into TPM (Box 14) .............................26 Energy-Reduction Checklists for Combustion, Steam Generation, and Process Heating Systems (Box 15) .................................................................................27 Over-Sized Equipment (Box 16) .....................................................................................................28 Three Ways to Right Size Your Fan System (Box 17) ....................................................................29 Flow and Energy Use (Box 18) .......................................................................................................29 Figures Share of Energy Consumed by Major Sectors of the U.S. Economy, 2005 (Figure 1) ....................2 Lean and Energy Management Roadmap (Figure 2) ......................................................................6 Sources of Energy Used for U.S. Industry and Manufacturing, 2005 (Figure 3) ............................9 Example Value Stream Map (Figure 4) ..........................................................................................20 Example Process Data Box with Energy Use Data (Figure 5) .......................................................21 Example Visual Control (Figure 6) ................................................................................................30 Dashboard Visual Controls (Figure 7) ...........................................................................................31 Tables Table 1: Manufacturing Sector Inputs for Heat, Power, and Electricity Generation by End Use .11 Table 2: Electrical Power Bill Analysis Worksheet .........................................................................13 Table 3: Energy Use Hidden in Lean Wastes ..................................................................................14 Table 4: Example Actions Identifi ed at a Kaizen Event .................................................................24 i Executive Summary Executive Summary The U.S. Environmental Protection Agency (EPA) developed this Lean and Energy Toolkit to assist organizations in reducing energy use and improving performance through Lean manufacturing— the production system developed by Toyota. Drawing from the experiences and best practices of multiple industry and government partners, this toolkit describes practical strategies and techniques to improve energy and environmental performance while achieving Lean goals such as improved quality, reduced waste, and increased customer responsiveness. There are at least three reasons for integrating Lean and energy effi ciency efforts: 1. Cost Savings: Reducing energy costs has a signifi cant impact on business performance, though costs may be hidden in overhead or facility accounts. 2. Climate Change and Environmental Risk: Proactively addressing the environmental and climate impacts of energy use is increasingly important to industry and society. Failure to do so is a potential business risk. 3. Competitive Advantage: Lowering recurring operating costs, improving staff morale, and responding to customer expectations for environmental performance and energy effi ciency increases your competitive advantage. Linking Lean and Energy Use Considerable energy savings typically ride the coattails of Lean activities because of Lean’s focus on eliminating non-value added activities (waste). Without explicit consideration of energy wastes, however, Lean may overlook signifi cant opportunities to improve performance and reduce costs. Companies such as Baxter International, Eastman Kodak, General Electric, Toyota, and 3M, as well as many smaller manufacturers, have successfully used Lean methods to reduce energy use, risks, and costs (see textbox). Example Results From Lean and Energy Improvement Efforts ✓ A Baxter International facility saved $300,000 in energy costs in one year. ✓ General Electric has reduced greenhouse gas emissions by 250,000 metric tons and saved $70 million in energy costs since 2005 at facilities worldwide. ✓ Toyota Motor Manufacturing North America reduced facility energy use and greenhouse gas emissions by 30 percent per vehicle since 2000. This toolkit describes a range of strategies for identifying Lean and energy improvement opportuni- ties and reducing energy use with Lean methods. It is not necessary to implement all the techniques in the toolkit to succeed; instead, select and adapt the approaches that make the most sense for your organization. iv Preface and visual controls. Chapter 5 discusses additional ideas for achieving process excellence with less energy use and environmental impacts. 1 CHAPTER 1 Introduction Benefi ts of Coordinating Lean and Energy Management Energy is a vital (and often costly) input to most production processes and value streams. By thinking explicitly about unnecessary energy use as another “deadly waste,” Lean implementers can signifi cantly reduce costs and enhance competitiveness, while also achieving environmental performance goals. Benefi ts of Coordinating Lean & Energy Management (Box 1) ✓ Reduce operating and maintenance costs ✓ Reduce vulnerability to energy and fuel price increases ✓ Meet customer expectations ✓ Enhance productivity ✓ Improve safety ✓ Improve employee morale and commitment ✓ Improve environmental quality ✓ Reduce greenhouse gas emissions ✓ Remain below air permitting emission thresholds ✓ Increase overall profi t Many organizations can fi nd it diffi cult to get senior managers to focus attention on energy use. En- ergy use is often viewed as a necessary support cost of doing business, and energy-effi ciency efforts can sometimes have diffi culty competing for organizational attention with other core operational needs. By linking energy management to Lean activities, energy-reduction efforts can be tied more directly to process improvement efforts that are regarded by senior managers as being vital to busi- ness success. In effect, energy improvements can ride the coattails of Lean activity while bringing signifi cant benefi ts to the organization. 2 Chapter 1: Introduction Cost Savings Energy costs can have a signifi cant impact on the fi nancial performance of businesses. A September 2005 poll taken by the National Association of Manufacturers (NAM) revealed that 93 percent of directors from small and medium-sized manufacturing companies believe that higher energy prices are having a negative impact on their bottom line.1 Substantial opportunities exist to reduce energy waste in the industrial and manufacturing sectors. No segment of the U.S. economy has as much to gain from energy-use reduction as the manufactur- ing sector, as Figure 1 illustrates. Manufacturers are affected directly by the energy cost of making prod- ucts (manufacturing), maintaining offi ce operations (commercial), and receiving raw materials and delivering fi nished goods (transportation). Energy use and cost information is, however, often decentralized and hidden from view in overhead or facilities accounts. Explicitly considering energy use in Lean implementation can reveal these hidden cost-reduction opportunities. And these opportuni- ties have proven to be worth uncovering, as many companies have achieved signifi cant cost savings as a result of energy reductions from Lean implemen- tation. Reducing energy use and increasing energy effi ciency is a proven strategy for cutting and controlling costs. Industry & Manufacturing 32% Residential 22% Commercial 18% Transportation 28% Share of Energy Consumed by Major Sectors of the U.S. Economy, 2005 (Figure 1) Source: U.S. Energy Information Administration, Annual Energy Review 2005, Washington, DC, July 2006. www.eia.doe.gov. 1 National Association of Manufacturers (NAM), Energy Effi ciency, Water and Waste-Reduction Guidebook for Manufacturers: Proven Ways to Reduce Your Costs and Improve Operations. www.nam.org/s_nam/bin.asp?CID=202138&DID=233434&DOC=FI LE.PDF,( viewed September 2007), p. 5. 5 Chapter 1: Introduction Lean and Energy: A Powerful Opportunity This toolkit discusses how Lean can play a powerful role in reducing energy use and costs. In many cases, energy effi ciency improvements ride the coattails of Lean. For example, right-sized equip- ment typically consumes less energy, and inventory reductions reduce demand for fl oor space that requires lighting, heating, ventilation, and air conditioning. By explicitly considering energy use in Lean efforts, organizations can often identify additional opportunities to save energy. While the U.S. economy has made substantial improvements in energy effi ciency in recent decades, there are signifi cant opportunities for businesses to further improve energy effi ciency. From 1975 to 2005, U.S. energy intensity (defi ned as the primary energy consumption per dollar of real gross do- mestic product, or GDP) dropped by 46 percent. Several recent studies, however, suggest that energy use could be reduced in the manufacturing and industrial sector by 75 percent at little cost using currently available technologies. Lean can help to identify and address these opportunities. Strategic Lean and Energy Management Creating a Roadmap for Lean and Energy Efforts For a variety of reasons, your facility may wish to pro-actively manage and reduce its energy use, while also achieving Lean goals such as improved quality, reduced waste, and increased customer responsiveness. Energy management is a systematic framework for understanding and identify- ing energy-related improvement opportunities. Energy management systems can be tailored to suit your facility’s needs, business opportunities, market risks, and specifi c goals and targets. If you are interested in gaining outside assistance, the ENERGY STAR program is a resource for manufacturers interested in developing energy management programs. An energy management framework can help you coordinate your company’s energy reduction ef- forts with its Lean efforts. Strategically and systematically integrating energy and Lean improvement efforts will enhance their effectiveness and the value they bring to your company. Why Be Strategic About Energy Management? (Box 4) ✓ Find new opportunities to reduce wastes, energy, and costs ✓ Reduce risks associated with an unreliable supply of energy, variable energy prices, and potential future climate change regulations ✓ Position your company to be a leader in energy and environmental performance ✓ Ensure that energy effi ciency efforts support other organizational objectives and improvement processes, such as Lean and Six Sigma Even if your organization decides not to pursue a strategic approach to energy management, there are numerous practical ways to consider energy waste and improvement opportunities during Lean implementation. Chapters 3-5 of this toolkit contain many ideas for doing this. 6 Chapter 1: Introduction There are four general steps involved in developing an energy planning and management roadmap appropriate to your organization, as follows.5 1. Initial Assessment: Consider the opportunities, risks, and costs associated with strategic energy management. 2. Design Process: Understand your company’s energy needs and how to approach energy management at your company. 3. Evaluate Opportunities: Identify and prioritize energy-related improvement opportuni- ties, such as energy-effi ciency actions, energy-supply options, and energy-related products and services. 4. Implementation: Use a management system such as the ENERGY STAR Guidelines for Energy Management to implement energy opportunities.6 Each of these steps is important for developing and implementing a strategy for Lean and energy improvements at your organization. Figure 2 presents a roadmap for energy planning and manage- ment that identifi es potential connections to Lean methods and improvement techniques outlined in this toolkit. 5 Bennett, Charles J. and Whiting, Meredith Armstrong. “Business & Energy in the 21st Century, Navigating Energy Management: A Roadmap for Business.” The Conference Board Executive Action Series. No. 160. September 2005. 6 The ENERGY STAR Guidelines for Energy Management are available at: www.energystar.gov/index.cfm?c=guidelines.guidelines_ index. Chapter 1 Chapter 2 Chapter 3 Chapters 4 & 5 Select energy management approach: •Set goals and metrics •Decide scale •Allocate resources •Integrate with Lean and Six Sigma Understand baseline and identify opportunities: •Energy assessments •Value stream mapping •Energy treasure hunts •Six Sigma Step 1 Initial Assessment Step 2 Design Process Step 3 Evaluate Opportunities Step 4 Implementation Understand the business opportunities related to strategic energy management: •Benefits •Costs •Risks Implement with kaizen events Energy efficiency: •Total productive maintenance •Right -sizing •Standard work •Plant layout Energy supply options Products and services Lean and Energy Toolkit Connections Lean and Energy Management Roadmap (Figure 2) Source: Adapted from Bennett, Charles J. and Whiting, Meredith Armstrong. Business & Energy in the 21st Century, Navigating Energy Management: A Roadmap for Business, The Conference Board Executive Action Series, No. 160. 7 Chapter 1: Introduction Chapters 1 and 2 of this toolkit support steps 1 and 2 of the roadmap, in that they can help your organization understand the relationship of Lean to energy use and the benefi ts of systematically reducing energy use through Lean. Chapters 3–5 of the toolkit describe how to identify and imple- ment energy savings opportunities in the context of Lean, supporting steps 3 and 4 of the roadmap. These strategies leverage Lean methods such as value stream mapping, kaizen events, total produc- tive maintenance, and standard work to improve energy and operational performance, while also incorporating energy assessment and reduction tools that can enhance Lean implementation. Lean and energy management can work together to increase profi t, enhance productivity, and de- crease energy consumption through sustained and continual improvements. This toolkit is designed to help your facility achieve these goals. To Consider • How well coordinated are Lean activities and energy-effi ciency efforts at your organization? • Who makes decisions involving energy use at your facility or company? • How are energy costs allocated at your company? Are costs billed to over- head accounts or are they assigned to individual departments or value streams? • How could your company benefi t from improved Lean and energy management? 10 Chapter 2: Overview of Energy Use and Lean Energy End Uses: What Do We Use Energy to Do? (Box 5) ✓ Heating, ventilating, and air conditioning (HVAC) ✓ Lighting ✓ Process equipment operation ✓ Process heating and cooling ✓ Transportation While identifying energy end uses is often straightforward, determining the amount of energy used by each end use can be challenging—but end use information is essential to targeting waste and improvement opportunities. In the context of Lean, it may even be useful to understand energy end use information at the process and equipment levels. Chapter 3 discusses some strategies and techniques for better understanding energy uses and costs at your facility. Looking at energy end uses across the manufacturing sector in the U.S. economy provides an indica- tion of where effi ciency improvement opportunities may exist. Tapping into sector-specifi c resources can help companies identify additional areas of effi ciency opportunity within their sector (see Ap- pendix B for information on sector-focused energy reduction resources). Process heating accounts for 53 percent of direct energy end use at manufacturing facilities, while machine drives and motors account for another 22.1 percent, according to a recent study by NAM (see Table 1). Chapter 4 describes specifi c strategies for reducing the energy used by these and other types of processes. Consider targeting your facility’s energy effi ciency efforts on two key end uses that are likely to account for a signifi cant portion of your facility’s energy use. As shown in Table 1, the following end uses typically have energy savings opportunities: 1. Process heat 2. Machine drives and motors For facilities without these types of energy end uses, HVAC systems and lighting may be good end uses to target. 11 Chapter 2: Overview of Energy Use and Lean Table 1: Manufacturing Sector Inputs for Heat, Power, and Electricity Generation by End Use Industrial Sector End Use Category Trillion British thermal unit (Btu) Percentage of Total Direct End Use Indirect End Use (Boiler Fuel) 3,635 Direct End Use 7,655 100% All Process Uses 6,323 82.6% Process Heating 4,055 53.0% Machine Drive 1,691 22.1% Electrochemical Process 298 3.9% Process Cooling and Refrigeration 210 2.7% Other Process Uses 69 0.9% All Non-Process Uses 1,314 17.2% Facility Heating, Ventilation and Air Conditioning 692 9.0% Facility Lighting 211 2.8% Conventional Electricity Generation 243 3.2% Other Facility Support 96 1.3% Onsite Transportation 69 0.9% Other Non-Process Uses 3 0.0% End Use Not Reported 157 Total 11,447 Source: Prepared by the Leonardo Academy from U.S. Department of Energy data, 1998 Data from Annual Energy View 2003, published September 2004. 12 Chapter 2: Overview of Energy Use and Lean Understand the Costs of Energy Use Understanding the costs of energy use can raise awareness of the potential value of identifying and eliminating energy waste during a Lean event. The costs of energy use are not always “visible” to production managers because they are rolled up into facility overhead costs, rather than as- signed to production areas. Explicitly tracking costs associated with individual processes or equip- ment can encourage energy conservation. If, however, cost savings from energy effi ciency improve- ments revert to overhead, or result in lower future budgets, production managers may not have an incentive to reduce energy use. It may therefore be necessary to create incentives for reducing energy use by sharing energy savings. One of the primary data sources for energy cost data is your facility’s utility bill. Utility bills often include the following types of data: • Consumption Charges: Electricity is charged based, in part, on the amount of electricity used (in kilowatt-hours, kWh) in a billing period. The per kilowatt-hour rate for electricity may vary based on the time of year (e.g., winter or summer season) and/or the time of day (peak or off-peak hours). • Demand Charges: For many electricity customers (all but small accounts), there will be a demand charge (per kilowatt) in the bill that is based on the peak electricity use each month averaged over a short time period (e.g., 15 minutes). Your facility may pay more for demand costs than consumption costs, although the two costs may be a single line item in the utility bill. • Fuel Costs: For natural gas and other fuels, you may be charged for the amount of fuel you receive (for natural gas this is based on a per therm price) and a delivery charge for the transportation and delivery of the fuel. Fuel charges may vary seasonally and based on the amount consumed. Because of variation in energy use and costs, it can be helpful to use spreadsheets or other systems to monitor your facility’s energy performance and costs over time. An example Electrical Power Bill Analysis Worksheet is below. Similar worksheets may be used to track monthly costs for natural gas and other fuels. 15 CHAPTER 3 Energy Assessment Strategies This chapter describes strategies and techniques for understanding how energy is used at your f acility and identifying opportunities to reduce energy use and costs. This chapter discusses the following strategies: A. Walk Through Processes to Observe Energy Use B. Energy Audits and Measuring Energy Use C. Examine Energy Use with Value Stream Mapping D. Use Six Sigma to Find and Eliminate Energy Waste and Variation E. Eliminate Energy Wastes in Kaizen Events A. Walk Through Processes to Observe Energy Use Walking through and observing processes as they actually run at a facility can be a simple, but ef- fective way to identify waste and fi nd improvement opportunities. During the walk through, look for signs of unnecessary or ineffi cient energy use. Ask questions, such as the Questions for Understand- ing Energy Use below (Box 6), to learn more about potential opportunities to reduce energy use. Questions for Understanding Energy Use (Box 6) Motors and Machines ✓ Are machines left running when not in operation? If so, why? ✓ Are energy effi cient motors, pumps, and equipment used? ✓ Are motors, pumps, and equipment sized according to their loads? Do motor systems use variable speed drive controls? Compressed Air ✓ If compressed air is used, do you notice any leaks in the compressed air system? ✓ Do compressed air systems use the minimum pressure needed to operate equipment? Lighting ✓ Is lighting focused where workers need it? ✓ Is lighting controlled by motion sensors in warehouses, storage areas, and other areas that are intermittently used? ✓ Are energy-effi cient fl uorescent light bulbs used? 16 Chapter 3: Energy Assessment Strategies Questions for Understanding Energy Use (Continued) Process Heating ✓ Are oven and process heating temperatures maintained at higher levels than necessary? Facility Heating and Cooling ✓ Are work areas heated or cooled more than necessary? ✓ Do employees have control over heating and cooling in their work areas? ✓ Are exterior windows or doors opened to adjust heating and cooling? Walk throughs are a key step in value stream mapping and other Lean activities. Companies such as Toyota and GE frequently conduct “Energy Treasure Hunts” to fi nd energy savings (see Box 7). An Energy Treasure Hunt is a three-day plant assessment event in which a cross-functional team of employees identifi es opportunities to reduce unnecessary energy use. Project teams then implement the ideas that are likely to yield the greatest benefi ts through kaizen events. Energy Treasure Hunts at General Electric (Box 7) With mentoring assistance from Toyota, General Electric (GE) launched an inte- grated Lean and energy initiative that has identifi ed upwards of $100 million in energy savings through energy treasure hunts. GE’s corporate commitment to energy use and greenhouse gas reductions has helped drive this effort. From 2005 to 2007, GE: ✓ Conducted over 200 energy treasure hunts at GE facilities worldwide, and trained over 2,500 employees on how to conduct treasure hunts ✓ Used energy treasure hunts to identify 5,000 related kaizen projects, most of which are funded and in various stages of implementation ✓ Reduced greenhouse gas emissions by 250,000 metric tons and realized $70 million in energy cost savings from implemented projects Source: General Electric, Ecomagination / Energy Treasure Hunt Team, 2007. B. Energy Audits and Measuring Energy Use While a walk through is an excellent way to identify and fi x energy wastes that are readily apparent, you may be leaving energy savings on the table unless you examine energy use more closely. Two strategies for learning more include: 1. Conduct an energy audit to understand how energy is used—and possibly wasted—across your facility. 2. Measure the energy use of individual production and support processes. 17 Chapter 3: Energy Assessment Strategies 1. Energy Audits An energy audit, sometimes referred to as an energy assessment, is a study of the energy end uses and performance of a facility. Energy audits can range in complexity and level of detail, from a simple audit involving a facility walk through and review of utility bills, to a comprehensive analysis of historical energy use and energy-effi ciency investment options. Energy audits allow managers to compare a plant’s energy use to industry benchmarks and identify specifi c energy savings opportu- nities. In many locations, local utilities or non-profi t manufacturing assistance organizations provide energy audit services for free or at reduced cost. There also are free tools available to help compa- nies conduct energy audits. Appendix A describes service providers, resources, and tools for energy assessments. Energy Savings From “Lean and Clean” Assessments (Box 8) ✓ The Green Suppliers Network, a partnership between EPA and the National Institute of Standards and Technology Manufacturing Extension Partnership, conducts “Lean and Clean” assessments for small and medium-sized com- panies. ✓ As of 2007, 49 assessments have identifi ed energy savings of 247,165 million Btu and over 72 million kWh. ✓ These assessments also identifi ed about $7.5 million per year in environ- mental savings and about $19.1 million per year in Lean savings. ✓ See www.greensuppliers.gov for more information. 2. Measuring Energy Use of Individual Processes You may not really know which process or process step uses the most energy—and therefore where the greatest energy savings might be—until you actually measure the energy use. During the analysis of the “current state” of a value stream or an individual process, collect data on how much energy each operation uses. Typical energy metrics include: • Kilowatt-hours (for electricity) • Therms (for natural gas) • British thermal units (Btu) • Energy intensity (energy use per production unit) • Energy costs (dollar amount spent on energy) Common Energy Units (Box 9) Energy Units Energy Equivalent 1 kilowatt-hour 3,412 Btu 1 Therm 100,000 Btu 1 cubic foot natural gas 1,000 Btu 1 horsepower 746 Watts 20 Example Value Stream Map (Figure 4) Source: Packaging Plus LLC and California Manufacturing Technology Consulting Chapter 3: Energy Assessment Strategies L o o k f o r e n e rg y r e d u c ti o n o p p o rt u n it ie s h e re ! 21 Chapter 3: Energy Assessment Strategies Another opportunity is to incorporate energy use data directly into current and future state value stream maps. Consider adding data on the average energy use or energy intensity of each process to the process data boxes in value stream maps, along with other regularly collected metrics. This will make it easier to spot key energy savings opportunities in the context of other improvement oppor- tunities. Figure 5 shows an example process data box with energy use data (in kilowatt-hours per pound of output). Combining energy use analysis and value stream mapping is a proven technique for cutting energy costs and improving productivity. For example, the California Manufacturing Technology Consulting, a Manufacturing Extension Partnership center in Cali- fornia, has partnered with a local utility and an energy effi ciency fi rm, Alternative Energy Systems Consulting, Inc., to conduct “Value and Energy Stream Mapping” projects with facilities (see Box 10 for examples). Identifying Opportunities Incorporating energy analysis into value stream mapping allows your team to consider energy reduction opportunities alongside other process improvement opportunities. You may fi nd ways to reduce energy use that will also provide other production benefi ts, such as fewer defects from more reliable equipment. Here are a few things to consider: • Key Questions: When you look at energy uses in the context of the entire value stream, ask two fundamental questions: o Is this energy end use needed? o Is there a way to deliver this end use more effi ciently? • Eliminating Energy End Uses: Eliminating entire energy end uses can result in sub- stantial cost savings, improve production fl ow, and simplify processes. For example, when planning for a Lean and environment kaizen event, a Lasco Bathware manufacturing plant found it could eliminate a shrink-wrap heating oven. This resulted in an annual savings of $99,290 and 12.6 million cubic feet of natural gas.10 • Support Processes: Support processes may consume signifi cant amounts of energy. Even brief consideration of support processes in value stream mapping enables a Lean team to think more broadly when identifying wastes and improvement opportunities. Example Process Data Box with Energy Use Data (Figure 5) Milling 2 people C/T = 2 min C/O = 2 hr Uptime = 74% Energy/pound output = 1kWh 10 Washington State Department of Ecology. “Lean & Environment Case Study: Lasco Bathware.” Prepared by Pollution Prevention Resource Center and Ross & Associates Environmental Consulting, Ltd. Publication No. 07-04-009. April 2007. (www.ecy.wa.gov/ pubs/0704009.pdf). 22 Chapter 3: Energy Assessment Strategies For example, particular processes may produce air emissions that go to a pollution control device (e.g., a natural gas-fi red thermal oxidizer) or effl uent that is sent to a wastewater treatment plant. Other support processes include lighting, heating, and cooling. D. Use Six Sigma to Find and Eliminate Energy Waste and Variation Six Sigma refers to a collection of statistical analysis and process improvement tools designed to identify and eliminate variation (or defects) in a process. Although specifi c training is needed before using Six Sigma, many companies have added these methods to their continuous improvement toolbox, developing an improvement approach often known as Lean Six Sigma. Six Sigma analytical tools can be particularly useful for identifying energy waste in situations where there is a lot of en- ergy use and when process-level data are available. Statistical analysis and process control methods can help isolate the root causes of energy use fl uctuations and identify factors that result in energy waste. Lean Six Sigma helped the 3M Company reduce energy use by 27 percent (when indexed to net sales) from 2000 to 2005. 3M has set a corporate goal for further energy use reductions of 20 per- cent for the period from 2005 to 2010, and the company views Lean Six Sigma as critical to realizing this performance goal.11 Six Sigma and Energy Savings at Baxter International (Box 11) In a compelling example of Six Sigma and energy-effi ciency integration, a Bax- ter International facility in Spain saved €220,000 (approximately $300,000) in one year by installing energy meters, tracking daily energy use, and using kaizen events to reduce energy use. The facility recorded daily energy use for one year and used statistical process control (SPC) analyses to set a standard range of deviation. Each time energy use exceeded average use by 15 percent, the facility held a kaizen event to address the root causes of the peak. In addi- tion to cutting energy costs, this initiative lessened the facility’s overall energy use and variability. Source: Interview with Jenni Cawein, Manager, Corporate Environment, Health, and Safety Engineering, Baxter International, 30 May 2007. E. Conduct Energy Kaizen Events After identifying the production areas that consume large amounts of energy, your facility can further analyze and eliminate wasteful energy practices through kaizen events, or rapid process improvement events. In kaizen events, which typically last 3-5 days, a cross-functional team of employees identifi es and implements process changes to reduce wastes such as idle time, inventory, and defects. Kaizen events create important windows of opportunity to consider ways to eliminate 11 See U.S. EPA, “3M: Lean Six Sigma and Sustainability” case study, www.epa.gov/lean/studies/3m.htm. 25 CHAPTER 4 Energy Reduction Tools and Strategies This chapter describes best practices for reducing energy use with Lean methods, focusing on pro- cess-level opportunities. It includes the following strategies: A. Use Total Productive Maintenance to Reduce Equipment Energy Waste B. Replace Over-Sized and Ineffi cient Equipment with Right-Sized Equipment C. Design Plant Layout to Improve Flow and Reduce Energy Use D. Encourage Energy Effi ciency with Standard Work, Visual Controls, and Mistake-Proofi ng A. Use Total Productive Maintenance to Reduce Equipment Energy Waste Total productive maintenance (TPM) is a Lean method that focuses on optimizing the effectiveness of manufacturing equipment. TPM builds upon established equipment-management approaches and focuses on team-based maintenance that involves employees at every level and function. What is TPM? (Box 13) ✓ The goal of TPM is to build a robust enterprise by maximizing production system effi ciency (overall effectiveness). ✓ TPM addresses the entire production system lifecycle and builds a con- crete, shopfl oor-based system to prevent all losses. It aims to eliminate all accidents, defects, and breakdowns. ✓ TPM involves all departments, from production to development, sales, and administration. ✓ Everyone participates in TPM, from the top executive to shopfl oor employees. ✓ TPM achieves zero losses through overlapping team activities. Source: The Japan Institute of Plant Maintenance, eds., TPM For Every Operator, (Portland, OR: Productivity Press, 1996), p 11. Six Big Losses That Lower Equipment Effi ciency Increased equipment operating effi ciency reduces energy waste. When machines are optimally tuned to accomplish the desired work, energy inputs are most effi cient. TPM’s emphasis on equip- ment effi ciency can lead to reduced costs, increased productivity, and fewer defects. TPM focuses on 26 Chapter 4: Energy Reduction Tools and Strategies the six big losses that lead to equipment ineffi ciency: 1. Breakdowns 4. Reduced speed 2. Setup and adjustment loss 5. Defects and rework 3. Idling and minor stoppages 6. Start and yield loss Eradicating the six big losses maximizes the productivity of equipment throughout its lifetime. With proper equipment and systems maintenance, facilities can reduce manufacturing process defects and save an estimated 25 percent in energy costs.14 Consider using one or more of the Four Strategies for Integrating Energy-Reduction Efforts into TPM (Box 14) to improve energy and equipment effi ciency at your facility. This chapter focuses on describing energy savings opportunities associated with autonomous maintenance (strategy #1); other parts of this toolkit provide guidance on identifying energy wastes, conducting energy kaizen events, and developing energy management systems (strategies #2-4). Four Strategies for Integrating Energy-Reduction Efforts Into TPM (Box 14) ✓ Integrate energy-reduction opportunities into autonomous maintenance activities ✓ Train employees on how to identify energy wastes and how to increase equipment effi ciency through maintenance and operations ✓ Conduct energy kaizen events to make equipment more effi cient ✓ Build energy-effi ciency best practices into systems for management of safety, health, and environmental issues Autonomous Maintenance Improves Energy Effi ciency One distinctive aspect of TPM is autonomous maintenance. Autonomous maintenance refers to ongoing maintenance activities operators undertake on their own equipment. Typical activities include: (1) daily inspections, (2) lubrication, (3) parts replacement, (4) simple repairs, (5) abnor- mality detection, and (6) precision checks. Autonomous maintenance provides an opportunity to integrate process-level energy-reduction strategies into ongoing equipment maintenance. Many simple energy effi ciency best practices can be implemented without extensive analysis or effort. Autonomous maintenance already captures a number of best practices, such as cleaning, proper lubrication, and standardized maintenance practices. Your facility can enhance TPM effec- tiveness by integrating energy-reduction best practices for specifi c types of processes into ongoing autonomous maintenance activities. 14 Manufacturing Extension Partnership of Louisiana, “Energy Management.” mepol.org/site.php?pageID=180, accessed 13 June 2007. 27 Chapter 4: Energy Reduction Tools and Strategies Use checklists such as the Energy-Reduction Checklists for Combustion, Steam Generation, and Process Heating Systems (Box 15) to identify opportunities to decrease energy consumption while also increasing equipment effi ciency. These checklists are based on best practices compiled by the U.S. DOE’s Energy Effi ciency and Renewable Energy Department. Energy-Reduction Checklists for Combustion, Steam Generation, and Process Heating Systems (Box 15) Combustion Systems ✓ Operate furnaces and boilers at or close to design capacity ✓ Reduce excess air used for combustion ✓ Clean heat transfer surfaces ✓ Reduce radiation losses from openings ✓ Use proper furnace or boiler insulation to reduce wall heat losses ✓ Adequately insulate air or water-cooled surfaces exposed to the furnace environment and steam lines leaving the boiler ✓ Install air preheat or other heat recovery equipment Steam Generation Systems ✓ Improve water treatment to minimize boiler blowdown ✓ Optimize deaerator vent rate ✓ Repair steam leaks ✓ Minimize vented steam ✓ Implement effective steam trap maintenance program Process Heating Systems ✓ Minimize air leakage into the furnace by sealing openings ✓ Maintain proper, slightly positive furnace pressure ✓ Reduce weight of or eliminate material handling fi xtures ✓ Modify the furnace system or use a separate heating system to recover furnace exhaust gas heat ✓ Recover part of the furnace exhaust heat for use in lower-temperature processes Source: U.S. DOE, Energy Effi ciency and Renewable Energy Website, “20 Ways to Save Energy Now.” www.eere.energy.gov/ consumer/industry/20ways.html, accessed 13 June 2007. By training operators on energy-reduction best practices and checklists applicable to manufacturing processes and equipment at your facility, operators will be better able to save energy in their day-to- day operations and maintenance activities. 30 Chapter 4: Energy Reduction Tools and Strategies D. Encourage Energy Effi ciency with Standard Work, Visual Controls, and Mistake-Proofi ng Standard Work and Energy Use Standard work is an agreed-upon set of work procedures that establish the best and most reliable method of performing a task or operation. The overall goals of standard work are to maximize performance while minimizing waste in each operation and workload. Standard work is the fi nal stage of Lean implementation in that it helps sustain previous Lean improvements and serves as the foundation for future continuous improvement (kaizen) efforts. Your facility can maximize Lean and energy gains by incorporating energy reduction best practices into standard work (e.g., consider drawing from the Questions for Understanding Energy Use and the Energy-Reduction Checklists in Boxes 6 and 13 of this toolkit). Example uses of standard work include: • Build energy reduction best practices into training materials, in-house regulations, and standard work for equipment operation and maintenance • Include energy reduction tips in weekly team meetings and monthly facility newsletters • Add energy reduction best practices into “shine” checklists used when implementing 5S (or 5S+Safety)15 Visual Controls Visual controls are used to reinforce standardized proce- dures and to display the status of an activity so every em- ployee can see it and take appropriate action. Visual controls also standardize energy and equipment use best practices and can be adopted facility-wide along with other in-house standards. These easy-to-use cues can be as simple as the following techniques: • Color-code pipes and other facility conveyances to help operators quickly identify and report key infor- mation (e.g., leaks) • Install a sign over on/off switches or power outlets to remind operators to turn off or un- plug equipment that is not in use (for example, see fi gure 6) Example Visual Control (Figure 6) Unplug When Not in Use 15 5S is a Lean method involving fi ve steps (Sort, Set in order, Shine, Standardize, and Sustain) to establish a clean, neat, and orderly workplace. Many companies add a sixth “S” for Safety. 31 Chapter 4: Energy Reduction Tools and Strategies Visual controls also provide a powerful way to track actual results against targets and goals, and encourage additional improvement. Figure 7 shows a dashboard representation of how energy use and cost at a facility compares to annual goals. Mistake-Proofi ng Mistake-proofi ng (also known by the Japanese term poka-yoke) refers to technology and proce- dures designed to prevent defects and equipment malfunction during manufacturing processes. Mistake-proofi ng is used by manufacturers to prevent and easily identify operational errors; it offers an unobtrusive approach to standardizing equipment use. One simple energy-effi cient action is to automatically power down energy-consuming equipment when not in use. Process equipment and lighting do not always need to be on or energized. Mistake- proofi ng devices such as occupancy sensors and lock-out/tag-out de-energizing steps are a simple, low-cost means to power down equipment that is not in use. By mistake-proofi ng equipment, a facility can waste less energy, time, and resources, as well as prevent rework. To Consider • Which of the Lean techniques mentioned in this chapter—TPM, fl ow, right- sized equipment, standard work, visual controls, and/or mistake-proofi ng— does your organization use? • What ideas do you have for using Lean techniques to integrate smart en- ergy habits into your organization’s work? Dashboard Visual Controls (Figure 7) Energy Use (KWh/$ Value Added) Annual Goal: 1.0 0 0.2 0.4 0.6 0.8 0.9 1.0 1.2 1.4 1.6 Energy Cost (cent/$ Value Added) 0 0.8 4.4 1.6 2.4 3.2 4.0 4.8 5.6 6.4 Annual Goal: 3.9 35 Chapter 5: Conclusion Your Thoughts on the Lean and Energy Toolkit Now that you have fi nished this toolkit, refl ect on what you read by answering these questions: • What strategies and tools in the toolkit seemed particularly interesting and useful? • What steps will you take next to improve Lean and energy management integration at your organization? • What Lean or other process improvement methods do you think might have good opportunities for improved Lean and energy performance? • What other information and tools would assist your organization to im- prove its Lean and energy effi ciency efforts? Please contact EPA to share your experiences with Lean and energy improve- ments and/or to discuss partnership opportunities by using the form found at: www.epa.gov/lean/auxfi les/contact.htm 37 Appendices Appendix A Energy Assessment Service Providers, Resources, and Tools This appendix describes resources for identifying public and private energy assessment service providers and provides information on several resources and tools for identifying energy savings op- portunities at manufacturing facilities. Energy Assessment Service Providers U.S. DOE Industrial Assessment Centers (IACs) www1.eere.energy.gov/industry/bestpractices/iacs.html IACs, which are located at 26 universities across the United States, provide no-cost energy and waste assessments to eligible small and medium-sized manufacturers. Teams of engineering faculty and students from IACs conduct energy audits or industrial assessments of manufacturing facilities and recommend actions to improve productivity, reduce waste, and save energy. U.S. DOE Best Practices Plant-Wide Energy Assessments www1.eere.energy.gov/industry/bestpractices/plant_wide_assessments.html Mid-size and large manufacturers can apply for a cost-shared Plant-Wide Energy Assessment offered by U.S. DOE. The assessments are comprehensive and systematic examinations of energy use reduc- tion opportunities at industrial facilities. All major aspects of energy consumption are addressed, including process operations and plant utility systems. Plants are selected through an annual com- petitive solicitation process, with a maximum award of $100,000. U.S. DOE Save Energy Now Energy Savings Assessments www1.eere.energy.gov/industry/saveenergynow/ Through the Save Energy Now program, the U.S. DOE offers Energy Savings Assessments to the nation’s most energy-intensive manufacturing facilities. The focus of these assessments is on im- mediate opportunities to save energy and money, primarily by focusing on energy-intensive systems such as process heating, steam, pumps, fans, and compressed air. 41 Appendix B: Sector-Focused Energy Reduction Resources Appendix B Sector-Focused Energy Reduction Resources This appendix describes energy conservation and effi ciency resources that are tailored to particular industrial sectors. ENERGY STAR Industries in Focus www.energystar.gov/index.cfm?c=in_focus.bus_industries_focus ENERGY STAR’s Industries in Focus creates a momentum for energy performance improvements within individual manufacturing sectors. Focuses provide industry-specifi c energy management tools and resources, develop the corporate structure and systems to better manage energy, and re- duce energy use within an industry. Participation is voluntary; however, most companies welcome the opportunity to network with peers. Generally, focuses enjoy the participation of most of the major companies within an industry. Participating sectors include: • Cement manufacturing • Petrochemical processing • Corn refi ning • Petroleum refi ning • Food processing • Pharmaceutical manufacturing • Glass manufacturing • Pulp and paper • Motor vehicle manufacturing Energy Trends in Selected Manufacturing Sectors: Opportunities and Challenges for Environmentally Preferable Energy Outcomes www.epa.gov/sectors/energy/index.html This EPA publication outlines energy trends, energy-effi ciency opportunities, and energy challenges across selected manufacturing sectors. This report is an analytical document and does not convey any Agency decisions. The report’s fi ndings and policy options are based on the available data used in this analysis. Sectors profi led in this report include: • Aluminum • Metal casting • Cement • Metal fi nishing • Chemical • Motor vehicles • Food • Motor vehicle parts • Forest products • Petroleum refi ning • Iron & steel • Shipbuilding 42 Appendix B: Sector-Focused Energy Reduction Resources U.S. Department of Energy, Industrial Technologies Program (ITP) www1.eere.energy.gov/industry/about/index.html ITP leads national efforts to improve industrial energy effi ciency and environmental performance. ITP’s mission is to improve the energy intensity of the U.S. industrial sector through a coordinated program of research and development, validation, and dissemination of energy effi ciency technolo- gies and operating practices. ITP partners with industry and its many stakeholders to reduce our nation’s reliance on foreign energy sources, reduce environmental impacts, increase the use of renewable energy sources, improve competitiveness, and improve the quality of life for American workers, families, and communities. Sectors in the ITP program include: • Aluminum • Metal casting • Chemicals • Mining • Forest products • Petroleum refi ning • Glass • Steel 45 Appendix C: Energy Conversion Resources and Rules of Thumb for Estimating Energy Cost Savings 12. Benefi t of fuel switching: • Switching from electric heat to natural gas or #2 fuel oil can reduce heating costs by 78 percent. 13. Cost savings for demand reduction (or load shifting): • Move operating shift to off-peak times: $75 per hp per year. • Move “other electric equipment” to off-peak: $120 per kW per year. United States Environmental Protection Agency www.epa.gov/lean Revised-October 2007 EPA-100-K-07-003
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