Analysis of the effect of energy efficiency legislation on electric motors on turkish market

After industrial revolution, energy which is a leading sector all over the world gains more and more importance every year. Developed and developing economies of the world are planning and making high scale investments in energy supply and demand security, sustainability and efficiency. This requires significant actions on distribution, production and consumption of electric energy. One these actions is utilizing less energy consuming products or systems, regarding the comfort level continuity. Literally, this is the definition of energy efficiency. As some has misinterpreted, energy efficiency does not require to compromise on life standards. As energy-efficient products/systems are used, it will be possible to reduce the electric energy demand and consequently the supply. Additionally, production of electric energy still highly depends on fossil fuels. This causes huge amount of greenhouse gases emission which is recognized as the primary responsible of global warming. Especially regarding electric motors utilized in industry consumes one-third of electric energy of total consumption in the world, studies and regulations on efficiency of these products will bring significant savings. So, many countries and international foundations study on increasing efficiency of electric motors and encourage these kind of studies and also take precautions for use of energy-efficient electric motors. Electric motors are workhorses of almost all industries, particularly in production industry. Although there are several types of electric motors, one governing type named "squirrel caged asynchronous motor" or "induction motor" is mostly utilized in industry. This motor type can work for a long time without maintenance and continuously. One or three-phased options are available, but mostly three-phase versions are used because of high power needs. Induction motors are generally utilized in pumps, fans, compressors in industry and their range are available from a few kWs to some MWs. Working principle of induction motor is based on electromagnetism. Motor consists of two main parts: stator and rotor. Stator is the stationary part and its shape is a hollow cylinder. Rotor makes the rotational move around an axis. Supply voltage is applied to the windings of the stator and a rotational magnetic field occurs in the machine. This field reacts with the current induced in rotor bars and produces a force on the rotor bars, resulting a rotational movement of the rotor around an axis. This operation causes some energy losses on different ways, mostly occurs as heat. Because of the nature of current, some of energy transforms into heat while flowing through in a conductive medium. Current flowing in the windings and in the iron chassis of the motor cause heat. Also induction motors are equipped generally with an internal fan to cool itself. Because of friction and the wind of the fan, some power losses occur. All these components cause power loss in the machine, so induction motor efficiency depends on these losses. Decreasing these losses, in the other words, increasing the efficiency of induction motors will lead to significant energy savings all over the world. To determine the efficiency of induction motors, there are some internationally recognized standard test methods. Mostly preferred test method is IEEE – 112 Method B and IEC 60034-2-1 Method 2-1-1 B. These two methods are very similar, IEEE-112 Method B is mostly preferred in North America and the other is preferred generally in the rest of the world. Both methods require full load, cyclic load and no-load tests to determine the losses separately. Doing so provides low uncertainty for efficiency determination. Also some national and international organizations have specified minimum energy performance standards (MEPS) for electric motors. These standards set forth several energy efficiency levels regarding power, speed and type of motors. North America countries use NEMA MG-1 standard as MEPS. These are NEMA Efficiency, NEMA High Efficiency, NEMA Premium Efficency and NEMA Super Premium Efficiency from low efficiency to high, respectively. European Union and many other countries use IE codes IE1, IE2, IE3 and IE4 from low efficiency to high, respectively which are set forth by IEC. The past versions of IE code was EFF, which are EFF3, EFF2 and EFF1 from low efficecny to high, respectively and they are determined by European Manufacturers of Electric Machines and Power Electronics (CEMEP). Like many other energy consuming products, electric motors are subject to legal regulations as a result of increasing efficiency demands. According to Act of Energy Policy in the United States, motors to be sold shall meet the NEMA Premium Efficiency level except some like brake motors or integrated in and cannot be dismantled from a pump, fan etc. US regulations are almost are valid in Canada and Mexico. These countries have been regulating the market since the early 2000s. However, although efficiency levels are set by CEMEP in the early 2000s in Europe, these levels were applied on voluntary basis, until European Union began to regulate the market almost ten years later from the United States, in 2011. Today, MEPS regulations are in force in many countries like China, Brazil, South Korea, Japan, Australia. Following the European countries, Turkey set MEPS regulations namely, SGM 2012/2, in 2012. This regulation is the same as content and entry into force. As of January 1, 2017, 0,75 kW to 375 kW motors rating up to 1000V except for brake motors and some motors working under some special conditions are subject to regulations. These motors shall meet IE3 requirement or shall meet IE2 requirement and equipped with a variable speed drive. Turkish Ministry of Science, Industry and Technology is responsible of the execution of the regulation. One of the missions of the ministry is surveillance of electric motor market according to the regulation. For this purpose, randomly selected motors from the market are sent to Turkish Standards Institution (TSE) Electric Motors Laboratory located in Gebze, Kocaeli province, in order to be tested according to SGM 2012/2. From 2015 to 2017, 47 model motors were tested in laboratory and test results show that almost quarter of tested 47 motors were failed. TSE electric motor laboratory is accredited to international standards IEC, UL and CSA. The laboratory is able to test electric motors from 0,18 kW to 90 kW with a low uncertainty and high sensitivity. It was established in 2015 and it is planned to be upgraded to 375 kW. SGM 2012/2 and the equivalent European version 640/2009/EC both bring some tolerance to worldwide recognized IE2 and IE3 efficiency levels. Also both regulations permit IE2 motors equipped with variable speed drive. Additionally, there is no such a program on the surveillance of IE2 motors are to be equipped after sold. The only obligation about the IE2 motors is that the sentence "must be equipped with a variable speed drive" to be placed on the motor. Moreover, the tolerance in the regulations cause an efficiency decrease so that the IE2 nearly has the same efficiency values with IE1, also the IE3 decreases so nearly to the IE2. If the regulations continue bring tolerance, the expected transformation of the market may not be achieved. Regarding the long life cycles of electric motors, the effect will continue for years. On the other hand, U.S., South Korea, Japan, and China set IE3 or equivalent efficiency levels, Brazil and European Union is discussing the transition to IE3 level. Under these circumstances, Tukey should quickly set to IE3 levels. Also in this study, data of previously tested 5 motors of 236 motors of a company which is the greatest glass and glass products manufacturer of Turkey, were used and an efficiency inventory has been estimated. Regarding four different scenarios, amount of energy and money savings are calculated, depending on the selection of different efficiency classes in possible investments. Also investment's return ratio has is calculated for the company. In first scenario, all motors are to be replaced with regulation defined IE2; in the second, replaced with standard defined IE2; in the third, regulation defined IE3 and in the fourth, standard defined IE3. According to the calculations, regulation defined or standard defined IE3 motors are acceptable. Finally, the same calculations are implemented for Tukey in general, and it is suggested to decision makers to set standard defined IE3 level as mandatory.