TECHNOLOGY IN CONTEXT
Measure It - Fix It: Go Green by Improving Inefficient Products and Processes
Producing clean energy and using energy cleanly are big parts of improving the environment. Both can be achieved by using sound engineering methods and tools for benefits that are green both in terms of money and of the planet.
IRENE BEARLY NATIONAL INSTRUMENTS
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Over the past several years, the cause of all things “green” has gained incredible momentum. From celebrity endorsements to political campaigns to company slogans, reducing environmental impact and energy consumption has become a rallying point that has captured the attention of individuals, businesses and governments.
To address these concerns and adhere to government regulations, entire industries and organizations are rushing to create differentiated technologies and optimize their existing processes, all while maintaining profitability and sustainability.
Engineers and scientists worldwide are leading the charge to address this issue, for they have the unique opportunity to make a bigger impact on the environment than any government policy. Green engineering provides the tools, techniques and technologies needed to tackle these challenges.
Engineers who want to design devices that reduce power usage and emissions, create viable renewable energy technologies, and investigate the state of the global ecosystem need green engineering. Green engineering is the use of measurement and control techniques to design, develop and improve products, technologies and processes that result in environmental and economic benefits.
While all things environmental are the focus today, green engineering fundamentally possesses the same building blocks as other types of engineering innovation. First, designers must correctly evaluate the problem by measuring its real-world behavior. Armed with the data, designers can achieve the desired solution by improving system components or creating the next generation of products. In other words, measure it and fix it. Common measurements used in green engineering include power quality and consumption; vehicle and factory emissions, such as mercury and nitrogen oxides; and environmental parameters, including carbon, temperature and water quality.
Opportunities and Key Technologies
For those considering joining the green dream, two pointed questions appear at the top of their minds: is today’s technology viable enough to make an impact, and is this really a sustainable business opportunity? The good news is that many engineers have traveled down this path before. In addition, significant innovations in measurement, automation and design tools have made the technology components for green engineering not only easier to use, but also cheaper to acquire than before. Key technologies that enable green engineering include:
• High-speed and high-resolution measurements
• Domain-specific analysis libraries
• FPGAs for advanced control
• Graphical programming to measure and implement control
Some of these new technologies have resulted from the growth in the semiconductor business, which has led both to advances in the capabilities of analog-to-digital converters as well as decreased costs from the mass adoption of consumer electronics. Furthermore, new enhancements to existing design and engineering tools, such as graphical programming, have made them more accessible to domain experts rather than solely technology experts. By shifting the necessary technology directly into the hands of those who are closest to the problems, solutions can be implemented more quickly and more effectively than in the past.
Green engineering solutions span almost every market, ranging from the rapid advancement of environmentally friendly products, to the study of climate changes, to the development of sustainable renewable energy such as wind power and biofuels. Industrial applications, traditionally viewed as environmentally unfriendly, are also ideal for green engineering when one considers monitoring power quality, retrofitting and automating existing manufacturing plants, and designing new high-performance machines. These businesses can all benefit and better compete in the global economy by implementing more efficient, optimized systems and technologies.
The following case studies demonstrate green engineering in the application areas of renewable wind energy generation and energy consumption optimization in commercial and industrial air-conditioning systems.
Renewable Power Generation
Renewable power generation covers a wide range of technologies, including wind, solar (photovoltaic and thermal), biomass, geothermal, hydro, wave and even high-energy physics. Research and development in these areas are exploding around the world, driven by energy prices, government legislation and incentives for commercialization. More than 50 countries from a wide variety of political, geographical and economic backgrounds have set aggressive targets for the amount of energy generated from renewable sources (Table 1).
The latest global status reports state that clean energy technology supplies approximately 5 percent of the world’s total energy consumption. With government mandates of up to 60 percent and deadlines as early as 2010, engineers and scientists are rising to meet this daunting challenge at a worldwide scope, with an increasingly focused drive these recent years.
Wind energy is one of the fastest emerging areas, growing at a rate of 30 percent each year with an installation of more than 100 gigawatts. However, this industry has several key challenges to conquer before gaining acceptance as a mainstream energy supplier. For example, wind turbine manufacturers must scale up difficult processes to meet the increasing demand, such as automating manufacturing and test systems for components such as blades, generators and gearboxes. Plus, hardware-in-the-loop (HIL) simulations of the wind turbine’s mechanical and electrical properties are used to predict its behavior during variable wind conditions, and advanced control systems running the pitch/yaw drives help maintain a constant rotating speed while reducing damage on the turbine components during high winds. Then, during the actual execution of the wind turbine, all types of sensors, signal processing and data analysis are also needed to perform machine condition monitoring, power quality monitoring and structural health monitoring.
One factor out of the many involved in designing and implementing these large wind turbines involves minimizing their acoustic emissions to comply with the government noise standards. Engineers must optimize the wind farm layout while factoring in meteorological conditions and terrain to minimize the noise impact on the surrounding community. DELTA, located in Hørsholm, Denmark, has developed a custom measurement system for wind turbine noise testing to help engineers design wind farms by supplying data for predictions (Figure 1). This system uses a National Instruments (NI) PXI system with dynamic signal acquisition modules to acquire acoustic data from a microphone at the required frequencies.
The tests call for measurements of sound power level, one-third octave band levels, and tonality at wind speeds from 6 to 10 m/s. DELTA also developed their noiseLAB software using NI LabVIEW graphical programming, which allows for monitoring of the measurement data in real time and then provides a preliminary analysis immediately after the acquisition. All data is stored with high resolution, thus facilitating supplementary analyses.
Machine and Process Optimization
In the industrial and automation world, most applications are solved with traditional tools such as simple low-cost PLCs. However, systems are growing in complexity as engineers look for additional ways to optimize control and reduce wasted resources. These applications relentlessly push the capabilities of traditional systems, requiring higher loop rates, advanced control algorithms, more analog capabilities and better integration with the enterprise network. Programmable Automation Controllers (PACs) were introduced to meet these measurement and control needs, combining the powerful functionality of a PC with the ruggedness and reliability of a PLC.
In their “Programmable Logic Controllers Worldwide Outlook” study, Automation Research Corporation (ARC) identified five main PAC features, characterizing the functionality of the controller by defining the software capabilities. Because PACs are designed for more advanced applications, the software platform should have multi-domain functionality capable of combining motion, process, control and communication functions in the same logic environment. These functions should be seamlessly integrated into a single package, instead of existing as disparate software tools that work poorly with each other.
Furthermore, since all industrial applications require significant customization, the open and modular architecture of PAC hardware and software allows engineers to pick and choose the appropriate components for their design. To help simplify the system design, the use of high-level graphical development tools allows for easy translation between the engineer’s concept of the process into code that actually controls the machines.
To address the needs of custom industrial applications, National Instruments offers a family of PAC deployment platforms combined with the LabVIEW graphical programming environment. Chiller Energy Management System (CEMS) Engineering decided to use NI PACs in a green engineering application that involves improving and optimizing current systems used at work and in daily life. This Malaysian-based company specializes in energy management of large-scale, climate-controlled commercial and industrial facilities.
Centralized air-conditioning systems for large areas traditionally consist of multiple chillers that control air temperature by removing heat from a coolant liquid through vapor-compression or an absorption-refrigeration cycle. However, their default settings are typically not optimized for specific environments, such as the high heat and humidity of Southeast Asia. CEMS Engineering used NI tools, including programmable automation controllers (PAC) and LabVIEW, to acquire real-time input data directly from sensors on the chillers that was then processed to send new operating instructions to the chillers. These operating instructions are determined through a series of variance calculations of the real-time input data, proportional integral derivative (PID) control loops, principles of thermodynamics, heat transfer and advanced mathematical optimization, and other proprietary equations, resulting in reduced electricity bills and energy consumption up to 30 percent. Implementation of the CEMS Engineering system was completed within six months of commencement and is now installed and running at customer sites.
As the environmental and energy challenges of the world become more acute, innovative engineers and scientists must step up to measure and fix the world around them. Green applications will be the engineering and technology focus for the next five to ten years, and thus advances in green engineering will continue to empower researchers and developers to both solve complex environmental issues and improve their products and processes.