Many governments are now requiring plants to track and report their energy use and carbon emissions. In fact, in some countries, heavy energy users should report annually if they emit more than certain levels of CO2 equivalent (CO2e) from different sources such as combustion sources and machinery. For many organizations and companies, it’s a daunting task to reduce CO2e emissions while increasing production capacity. This leads to an energy supply and demand dilemma. Many parts of the world are seeing their peak margin (reserve) disappear with a robust economy and increasing demand for more products and power. In each developed or developing country, average electricity demand is growing up to 5% annually; electricity prices, and generally energy prices, will also rise constantly over the next five years due to different reasons, such as new carbon and environmental policies put in place. All of these lead to a demand for better energy monitoring and management in any plant and facility, offering relevant information to key individuals, engineers, and departments that enable improved energy performance. Energy management solutions should include comprehensive energy production and sustainability services leveraging a common platform.
Opportunities for savings
There are usually multiple opportunities for energy savings and emission reductions across each plant’s operations. An energy study should offer a single-source solution with the right combination of operational details, process design, technology, modeling, and energy and process optimization and control to achieve defined energy goals. Improved monitoring, operation, and control can capture hidden opportunities and identify areas that can be optimized with multivariable predictive control strategies without sacrificing throughput or yield.
Better heat recovery can help to reach higher levels of energy efficiency. A practical methodology that not only considers value and cost of improved heat recovery, but also seeks synergy in enhancing throughput and product quality, should be used.
Advanced process technologies should be considered and involved in a successful energy management exercise. These can offer significant opportunities for improved energy and plant performance. Technologies such as enhanced heat exchangers, high-performance internals, new reaction internals, power recovery turbines, and improved catalysts are part of an effective energy management plan.
Another key area is utilities optimization. In other words, one of the keys to reducing energy costs is balancing changing energy demands from the process with adequate supply from the utilities. Effective energy management should provide solutions to manage the supply/demand equation and optimize machinery and equipment operation such as steam turbine and boiler performance.
Fuel management is also important. In many plants 10-45% of input gases or hydrocarbons are used as fuel. Saving and recovering valuable components in fuel gas system, such as C2 recovery of fuel gases in some petrochemical plants, not only reduces emissions significantly, but also enhances plant performance, such as catalyst utilization, and product yields.
Energy monitoring and management exercises
To optimize energy consumption, the first step is monitoring; compact and powerful monitoring units for recording all consumption data related to energy and power generation, distribution, and consumption can be used. They can be linked to the automation, energy, and power management system.
The next step is “energy evaluation.” For energy management purposes, the energy data should be processed further. There are available energy management packages, and purpose-built or modified packages can be used. For instance, a suitable package should evaluate and display the generation, distribution, and consumption of energy and the associated energy costs of a plant. Thus, energy costs can be divided according to the consumers, permitting identification of high consumers and potential savings. Innovative energy and power management systems can provide the basis for economical and optimized energy management; such a system comprises the recording of energy data, data processing, versatile analysis, and forecasting options, as well as prediction of relevant energy data and parameters.
While energy monitoring and management can reduce energy costs by up 30% in new plants, the use of comprehensive technologies and tools such as energy-efficient electric motors or variable-speed drives can provide energy savings up to 60% in older plants.
Energy monitoring and management workshops, meetings, and one-to-one discussions: Energy workshops to identify new projects and review performance should be planned periodically. Frequent virtual meetings to share best practices and successes between locations can also be very effective if planned properly. An important consideration is, for some teams and groups, HAZOP-type meetings for energy management might not be effective; for instance, some technicians and engineers might not share their impressions or potential improvements in a formal meeting. Often one-to-one meetings can offer better opportunities for some energy management discussions.
Energy monitoring and management in maintenance and operations: This includes better operation of steam systems, insulation, and cooling towers for superior energy efficiency.
New technologies and facilities: Implementation of advanced process and machinery control technologies is an important consideration; waste heat recovery and combined heat and power concepts should be considered.
Machinery thermal monitoring and management
Over the past decade, thermal monitoring and management of machineries have started to receive more attention. In fact, with the increasing requirements for compactness, energy efficiency, cost reduction, lightweight design, and extreme temperatures, along with the need to fully exploit new topologies and materials, it is now necessary to analyze, monitor, and manage the thermal circuit of machinery to the same extent as the other aspects such as fluid dynamic.