Intralogistics systems and conveyor systems for airports or parcel centres have to reconcile various competing demands. Nord Drivesystems takes into account the operators' "Pains and Needs" in a comprehensive TCO approach that considers ecological issues as well as cost aspects. The specific problems can best be solved with individually matched drive systems that strive for an optimal compromise between energy efficiency and variant reduction.
Geared motors for the lower to medium power range do not in themselves have particularly high energy consumption, and the costs incurred are also moderate. However, if one considers the quantity and the operating hours of the drives as well as the life cycle costs incurred, high savings potentials reveal themselves in terms of energy and business management. Nord Drivesystems supplies between 50 and 20,000 drive systems per project for various intralogistics and baggage handling systems.
Such a drive usually runs in one to three shifts in intralogistics systems. Based on an average installed power of approx. 0.75 kW, a single drive system already represents roughly the electrical energy demand of a single-family household. The power consumption for the conveyor technology of a complete intralogistics or baggage conveyor system quickly reaches the magnitude of an entire community. When you consider that we are desperately seeking solutions to reduce CO2 emissions, it becomes clear that we should act. It makes sense in terms of climate policy and business management to exploit these savings potentials.
Know the cost drivers and act
The visible costs, i.e. the investment costs for a drive system, account for only 15 percent of the life-cycle costs. 85 percent of the costs result from later operation: energy costs, administrative costs, service and maintenance costs, training and documentation, personnel costs, spare parts stocking as well as failures and downtimes. In times of climate change, an important aspect in external presentation is the sustainability of the overall project. With rising raw material and energy prices, sustainable action will always have a positive impact on life cycle costs.
What can the operator of an intralogistics system do? For new facilities, he should take aspects such as sustainability and life cycle costs into account accordingly in the tender specifications. For existing facilities, an energy audit is recommended to identify starting points for targeted optimisation. Only an intensive examination of the project and its requirements as well as a careful consideration of all economic aspects will lead to the best result for the operator in the drive design. NORD's application engineers therefore support their customers right from the planning stage with comprehensive analysis and consulting services.
Dimension correctly, then install
The life cycle costs of drive solutions (Total Cost of Ownership/TCO) include all costs incurred: from acquisition to commissioning, use and maintenance to disposal. The two biggest levers for reducing TCO are energy consumption and the number of drive variants used. However, there is a conflict of objectives between the approaches of optimising energy efficiency and reducing the number of variants. If a system is designed with drives that are each designed for the most energy-efficient operating point, the pure investment costs are optimal and the motors run comparatively energy-efficiently, regardless of their efficiency class. In return, however, many different drive variants must be managed and maintained over the entire life cycle of the system.
While a drive concept with the main focus on saving energy costs leads to a large number of variants, a variant reduction has exactly the opposite goal, namely to cover the required torques and speeds in a system with as few different drive variants as economically feasible.
Efficiency and costs in perfect balance
The new IE5+ motor generation from Nord Drivesystems has been designed with a particular focus on use in the intralogistics industry. The particularly compact and energy-efficient synchronous motors offer consistently high efficiency over a wide torque range, providing optimum energy consumption performance even in partial load and partial speed ranges. Comparing a conventional IE3 asynchronous motor (0.75 kW, 83 % motor efficiency, helical bevel gearbox) with a corresponding IE5+ synchronous motor (0.75 kW, 93 % motor efficiency, helical bevel gearbox) results in an energy saving of approx. 11 % at 16 operating hours per day (4000 p.a.) and a CO2 emission factor of 366 g/kWh. This corresponds to about 400 kWh and 0.15 t CO2 per year.
Thanks to the optimised power density, the more compact IE5+ motor can also achieve space savings of up to 40 % compared to conventional asynchronous motors. This means that a more powerful motor with higher energy efficiency can be installed in the same space. Due to the higher power density, an IE5+ synchronous motor that delivers a torque of up to 4.8 Nm, for example, is just as large as a previous IE1 motor with 1.24 Nm.
Thanks to the modular, scalable motor design, three power classes are also possible in one housing by inserting one, two or three rotor packs into a uniform housing, depending on requirements. The new high performer also cuts a fine figure on the scales. Thanks to the efficient use of materials and compact installation space, the IE5+ synchronous motor achieves a weight advantage of over 50 % compared to IE3 asynchronous motors in the same power range. Nord Drivesystems supplies the IE5+ synchronous motors with motor efficiencies of up to 95 % for the power range from 0.35 to 4.0 kW and in TENV and TEFC versions.
Additional sustainability effects
Less volume and less weight also leads to lower transport costs and thus protects the environment. The IE3 version of the 0.75 kW motor mentioned above weighs around 10 kg, the comparable IE5+ motor only around 6 kg. If an IE5+ motor is delivered by truck from Hamburg to Stuttgart instead of an IE3 motor, the amount of CO2 emitted is reduced by about 120 g per motor. Considering the outlined plant sizes with up to 20,000 drives and the fact that Nord Drivesystems delivers drive systems around the globe, it becomes clear that the motors from the high-efficiency portfolio not only make a direct contribution to sustainability by reducing power consumption, but also an indirect one through their smaller volume and weight.
The next step: two becomes one
The fewer interfaces, the higher the system efficiency. With the DuoDrive, Nord Drivesystems has therefore now introduced a revolutionary geared motor in a hygienic washdown design, in which the IE5+ synchronous motor is accommodated in a housing together with a single-stage spur gear. As a system, the particularly compact DuoDrive concept achieves even significantly higher energy efficiency than the drive systems already described with IE5+ synchronous motor and bevel gearbox. With up to 92 % system efficiency, DuoDrive offers one of the highest efficiencies in this performance class on the market and also achieves very high system efficiency in partial load operation. This makes it future-proof and a true cost reducer.
The first available DuoDrive size covers gear ratios from i=3.24 to i=16.2 and is designed for the output torque range up to 80 Nm and speeds up to 1,000 min-1. Important features of the new DuoDrive geared motor, apart from the high system efficiency, are the consistent reduction of variants and the smooth, unventilated and compact design. Since many wearing parts are eliminated, maintenance costs are also reduced. The DuoDrive design can be mounted in different installation positions without any adjustments. This further reduces the number of variants in intralogistics projects. The compact housing dimensions result in another advantage: the DuoDrive is narrower than competitor products and thus offers a small aisle dimension in conveyor installations. Since the power of the geared motor can be scaled without changing the external dimensions in the same design, no change to the system layout is required for power adjustments.
A balanced combination of variant reduction and energy efficiency can result in high TCO reductions. The drive systems of the modern high-efficiency portfolio from Nord Drivesystems combine the advantages of both optimisation