Energy Optimization in manufacturing : Beyond installing LED and VFD
While investing in energy efficiency brings tax deduction for manufacturers, so far approach has been straight forward. Replace DC drives/Gearbox to AC Vector Drives. Change to LED Lamps. In both the cases, energy efficiency is achieved against ominous increase of harmonics in the line, which kills the motor core faster ( For details, please see the case study where we have seen up to 35% wastage of energy eroding any gain in replacement : "How MachineSense Helps You Measure Harmonics in Electrical Lines" )
However, a much higher degree of energy optimization is possible from following solutions if the factory allows more Industrial 4.0 installation to track their energy process.1. Optimize Descaling Operation: One of the largest source of energy usage is in Utility. Within the Utility Chiller units consume lion share. However scaling in water pipes reduces heat transfer efficiency resulting in more energy usage. Descaling regents or magnetic descaler should be used to reduce this wastage. But when to use them and how to use them needs Industrial 4.0 recommendation based on energy usage increase vs Descaling time.
2. Equalize the current distribution : Other common source of energy loss- uneven distribution of 3 phase load. This is also rampant in the factory as in most of the factories single phase power for office or light is taken out arbitrarily from only one phase instead of pulling out evenly from all the three phases . Uneven 3 phase creates harmonics which will be wasted in any inductive load operation.
3. Dryer Optimization: If the factory has to run big electrical Dryers, they are energy behemoth. Unfortunately around 20-40% of the energy wastage in dryer is widely commonplace. There are two major sources of wastage in Drying. First, Dryer will continue to be "ON" with warm dry air even when for hours, there will be no material feed to dry. Second, drying time may be much higher than necessary. 90% drying happens within first few minutes and if Drying time is not adjusted for material type, each time, there will be wastage from over drying.
4. Optimization of Extrusion load vs material feed: Extrusion is one of most common process in Plastic, Wood, Metal processing. Every extrusion process is energy hog. Energy is primarily consumed in big horse power puller Motor and Heater which melts the material. In Extrusion too, it is fairly common that the motors will be in "load" even when there is no material feed for hours. That's why it is extremely important to correlate "motor loading" condition with material feed status for better energy efficiency
5. Dynamic Set Point for HVAC: In manufacturing units, HVAC must be feeding several rooms and floors. Each floor is subjected to different weather and different level of populations. To avoid complexity of Optimization, HVAC output is normally set at nominal lowest point. If ambient of each room/floor is properly monitored, then an optimal set point can be achieved dynamically.
There are several more ways to optimize energy usage in a factory further. However each of the method, needs couple of common parameter set points- ambient temperature, energy usage, weather data, material feed rate, productivity of motors etc. For further details, please look at the product and solution of Machinesense LLC