By Ivan Romanow, CET
As energy price volatility continues, manufacturers are coming under increasing pressure to proactively manage their energy consumption while also maintaining compliance with evolving sustainability requirements. Many manufacturing companies, however, have not factored energy consumption into their planning or execution decisions because they don’t have the right data in the right context. A detailed understanding of the energy consumption for specific production areas, equipment and products, can help manufacturers better manage production planning and execution, as well as strategic contracting, in an informed and responsible manner.
Manufacturers need timely visibility into energy consumption at the local level to effectively manage their energy consumption. An effective manufacturing energy management strategy should:
• provide manufacturing context (product, batch, lot, equipment) for energy usage;
• provide near real-time visualization of contextualized energy information, which enables manufacturing personnel to optimize planning and execution decisions;
• outline where and why metering should be implemented;
• provide insight into the current baseline energy usage;
• integrate into operational excellence programs; and
• provide timely and accurate energy consumption data for performance management reporting and analysis.
Developing such a strategy should include the following steps:
1) Assess your energy costs
Energy management is not just about tracking energy consumption through utility bills, but more about how effective companies are when it comes to considering energy in operational decision-making. The best practice is to start with a baseline plant energy assessment. An experienced energy assessor can identify many savings measures. Energy awareness workshops also provide measuring and managing best practices, and help to identify energy improvement opportunities and strategies for implementing energy improvement projects.
2) Monitor and measure
Once the baseline data on current energy consumption has been determined and reduction targets are established, measurement and management of energy is necessary. This enables companies to benchmark themselves internally across functional groups, as well as externally against industry standards. It also allows management to continuously monitor and measure the success of the energy management programs and to make future decisions on scaling the program to other areas within the enterprise.
3) Understand when energy is used
An effective energy strategy combines production contexts such as volume, shift, crew, uptime/downtimes and major waste events (e.g. leaks). Dashboards and reports clearly define consumption patterns, identify peaks, valleys, ramp-ups, ramp-downs, peak demand and load duration curves. Armed with this data, it is easy to develop target settings to drive the right behaviour on the shop floor based on historical records and manufacturing specifications. The energy data allows for forecasting an energy budget based on projected production demand, and also provides a mechanism to validate energy balances and invoices.
4) Understand where energy is used
A critical feature of an energy management program is an annual energy audit of all operational systems, including the plant’s insulation, steam traps and lighting. As a result of these audits, many plant employees can participate in energy efficiency ideas, large and small, for management consideration. Energy-saving measures fall into two categories: capital projects (e.g. heat recovery from boiler flue gas, variable speed drives, compressor controls and the installation of high efficiency motors); and no cost or low-cost measures, which usually require continuous attention and the involvement of plant management (e.g. turning off pumps or lights when not in use, boiler combustion tune-up, maintenance of air filters, insulation, steam traps, fixing air and steam leaks). On average, low-cost operational measures comprise 40 to 50 percent of all energy-saving opportunities in an industrial plant.
5) Eliminate waste
Focus on the following areas:
• Thermal energy – It has been suggested that, on average, plants having significant thermal loads, including steam, process furnaces and building heating, can save about 20 percent of their fuel costs with a concerted energy program. This figure includes both capital and operating measures. To achieve this requires significant management involvement and commitment at all levels.
• Electricity – The potential saving of electrical energy is somewhat less than that of thermal energy. It is estimated that about 10 percent of total electrical energy consumption can be saved, mainly through motor improvements (e.g. VSDs fans, pumps and compressors). Other measures include power factor correction, automatic control of building HVAC, lighting improvements and air compressor system improvements.
• Water – For most industrial plants, water is a minor component of the total utility bill. Potential savings are 20 to 50 percent.
6) Maximize system efficiency
Leaving lights on when not required or having equipment idling while not in production is a waste of energy. Installing dimmers and timers tied to production schedules when full light is required or scheduling high-energy equipment to run at non-peak times are examples of maximizing system efficiency. Installing gas, steam, air or electricity meters together with the implementation of a management reporting system can save five to 20 percent of energy. In most cases, this type of project only works if the management imperative and training of personnel go along with the metering system. The information collected from the energy meter data and asset condition data can be used together to schedule maintenance activities. For example, if there is a compressor that is utilizing more energy than it is rated for, it can be flagged for a scheduled maintenance. Plant production scheduling, with the availability of real-time and historical energy data, can be used to lower costs by taking advantage of lower tariff rates while optimizing processes to be more energy efficient.
There are technologies and services to help Canadian manufacturers optimize energy use. Since the majority of energy consumed in all plants is done so by the equipment in the plants, investing in energy-efficient hardware, such as variable frequency drives, and energy efficient lighting are extremely helpful in reducing energy consumption. For example, VSDs can be used to save energy on rotating equipment such as fans, pumps and conveyors by controlling the speed of a motor through adjusting the power supplied to the equipment.
Employing consultants provides value through plant audits, helping executives to understand the gaps in energy management process and provide some critical recommendations on the steps required to make a plant more energy efficient.
Near real-time historian and integrated visualization tools help companies to automatically collect energy data, providing the decision makers with real-time insight into the energy processes that aid in operational decision-making. These tools allow companies to collect critical energy information, such as energy consumption, energy costs and energy efficiency, and drill down to data per production line, plant or product. This information is critical in making decisions on how to efficiently utilize energy.
Statistical process control software enables companies to establish limits and alerts management when the processes are out of control limits. Investing in analytics, dashboards and alert management provides the right energy data to the right person at the right time to enable decision-making.
Interoperability of energy management with asset management enables maintenance to consider energy consumption data while scheduling maintenance activities. Similarly, the integration of energy consumption data with advanced process control data enables plant operators to include critical information related to energy usage and cost in the optimization process, along with other variables on the plant floor, to achieve the optimal balance of output, quality and energy efficiency. Dashboards and analytical solutions will enable executives to understand the real value from a huge amount of energy data collected, and present the data in front of the appropriate employees for efficient decision-making.
Investing in renewable energy sources, such as solar, wind, landfill gas and biomass geothermal, are all viable solutions to be investigated. Ontario Power Authority has introduced the FIT program (Feed-in tariff) for industry that provides a 20-year contract to pay companies for the renewable energy they produce, which will have a major impact to your bottom line.
Operations can achieve rapid and substantial business benefits by implementing an integrated manufacturing energy management solution resulting in short term pay backs.
Ivan Romanow is the Director of Sales and Marketing at Gescan, a division of Sonepar Canada (www.gescanontario.com).
This article has been featured in the latest green issue of Manufacturing Automation Magazine on page 15.