Worldwide, total final energy use of manufacturing industry is equivalent to one third of the total final energy consumption of the global economy. Developing countries and the economies in transition account for 60% of industry’s total final energy consumption. Industry has significantly improved its energy efficiency in recent decades. But industry’s total energy use continues to grow as a result of continuing large increases in the volume of production. Production is expected to continue to expand very substantially in the coming decades, particularly in developing countries. As a result, modest energy efficiency improvement rates will not be sufficient to stabilise or decrease the sector’s energy demand in absolute terms. In order to make significant reductions, ambitious energy savings measures need to be implemented. International benchmarks are estimated for a total of 26 industrial processes, products and industry sectors. These processes include the energyintensive sectors such as the iron and steel, and chemical and petrochemical sectors, as well as number of light industries and small-scale sectors such as foundries and lime kilns. The total energy used by these processes represents approximately 60% of industry’s current final energy use. The analysis shows the existence of a worldwide potential to save 31 exajoule a year if all the processes reviewed were to operate at the level of the international benchmark. Excluding feedstock use, this is equivalent to a worldwide improvement potential of 26%, comprising a 15% to 20% potential improvement in industrialised countries and a potential improvement of 30% to 35% in developing countries and economies in transition. The potential saving varies sector by sector. The percentage improvement potentials are less than the worldwide average for energy-intensive processes and sectors, although most light industry processes show higher improvement potentials. A range of mandatory measures should be used to help drive industrial energy efficiency more effectively, including; energy performance targets, energy audits, energy managers, reporting, trading and adoption of standards such as ISO 50001. Additionally, the following technical tips for energy saving can be applied in various industries:
Metering: Metering is the most important part of any energy management programme. Effective metering enables sites to continuously improve their performance by monitoring energy consumption and benchmarking against metrics. Metering can help spot problems and abuses and enabling them to be resolved.
Lighting: Savings can be made by deploying efficient lamp technologies, such as LEDs, CFL and also energy saving halogen lighting. Savings of up to 80% are possible compared with traditional incandescent lamps.
High Efficiency Motors / Variable Speed Drive: Electric motors, which are the largest single consumer of electrical energy, can be found everywhere across industry and commerce; in fans, conveyor belts, pumps, lifts and air conditioning, just to list a few examples. The energy cost to run a motor for two months can be greater than the initial purchase price. Modern motors, to the new mandatory motor efficiency standards IE2, are substantially more efficient, paying back their purchase price within a few months. Users who employ an effective motor management policy which includes motors, Variable Speed Drives (VSDs), gearboxes and the driven machine can release further savings. Variable Speed Drives (VSDs) optimise the voltage and frequency supply to the motor to match the speed to the actual load demand, reducing energy consumption significantly. Even relatively small reductions in speed can produce significant energy savings.
Building Controls: You can achieve savings of anything up to 30% by installing and maintaining an effective building energy management system. Some of the easiest energy savings can be made through effectively managing building energy management system time clock schedules, to ensure plant is not running overnight, at Some of the easiest energy savings can be made through effectively managing building energy management system time clock schedules weekends or on bank holidays, unless required. Monitoring your environment controls can also help, ensuring that heating and cooling systems are not working against each other.
Intelligent Lighting Controls: Implementing intelligent lighting systems can save over 40% of energy used in lighting. Light fittings can be individually controlled to turn them off or even dim the output as required. Used in conjunction with light level sensors and presence detection, controls can be optimised to take full advantage of daylight savings and maximum off periods.
Increased Factory or Process Automation: Up to 80% of potential savings in a plant come from improved automation. Done correctly, automation can improve productivity, reduce downtime and minimise maintenance requirements – whilst simultaneously reducing energy consumption.
Power Controls: Power factor correction can improve the usable power available to equipment, and thus maximise its efficiency. Active harmonic control removes harmonics and other noise from power lines, which saves energy and also reduces wear and tear on electrical equipment. By scheduling production to off-peak times, and managing the electricity tariffs, you can use energy when it is cheaper, therefore reducing costs. You can also avoid penalties which may be incurred for taking electricity at peak times.
Efficient Heating and Cooling Technology: Between them, heating and cooling typically use around 20% to 40% of a building’s energy. Boilers and chillers are often old and inefficient. Replacing them with modern versions can help to substantially reduce the overall energy use of the building. A new condensing boiler can operate at highly improved efficiency, whereas a conventional boiler will have an efficiency of only 80%. To put it another way: that’s a fourfold improvement. A modern variable speed chiller will typically have a coefficient performance (COP) of around 6, compared to a standard chiller’s COP of 4. A higher COP figure means less energy is required – thus reducing costs.
Combined Heat and Power: Combined Heat and Power (CHP) is the simultaneous generation of usable heat and electrical power in a single process. CHP offers a relatively long payback period, but can be well worth considering if you have a good use for the heat generated. If sized correctly, it can significantly reduce energy costs, consumption and CO₂ emissions.