Cut your energy bill before it is too late!
Electricity prices reach all time high in Europe and many industrial producers are under huge pressure. There is at least one thing that everyone can make, independent on the local government, EU commission etc: Reduce your energy consumption. In fact, you need to cut your energy bill before it is too late.
A year ago hardly anyone could imagine the energy prices as we witness them in the last weeks and months. What started with gas prices shooting up is now even worse in the electricity market. There is a mixture of reasons for this development. While it is almost impossible to make any prediction on the future prices there are ways to reduce your industrial energy consumption that are almost bullet proof.
The portion of energy cost in the overall cost structure depends on the industry, specific production process, level of automation etc. The energy intensive production is naturally hit the most. Thus, the need to reduce energy consumption becomes more important than ever.
At the same time we know that the energy saving potential is there. Even though the amount of variable frequency drives is steadily increasing, the motor manufacturers still produce many more fix-speed motors than those for variable speed operation (illustratively depicted in Figure 1, exact numbers not known). Thus, there is large installed base of machines operated direct on-line (DOL). Retrofitting them to variable frequency operation may bring interesting energy and cost savings.
Naturally, not every single application is suitable for VFD fed motors. However, many applications do benefit from VFDs. It is the task of energy saving assessment to determine whether a retrofit is perspective or not.
The energy efficiency assessment provides vital information about where to install a VFD, where it makes most sense. That is the low hanging fruit. It might be possible to install the first VFD and then invest into additional VFDs from the energy savings that you achieve. Thus, no large initial investment is required.
For example, let’s say that the payback of a variable speed drive system for a specific pump is 2.5 years. So after 2.5 years the investment pays back. After next 2.5 years the energy savings allow you to purchase another VFD, without any need to take a loan. In other words, you can re-invest your energy and $$ savings into technology that further reduces your energy consumption. It is like a snowball rolling down the hill and getting bigger and bigger. The size of the snowball represents your savings and your competitive edge.
How to invest into energy efficiency in a smart way
Smart investment into improved energy efficiency is normally the one with shortest payback. Our assessment helps you to discover the low hanging fruit. That is where the journey to reduced energy consumption and higher competitiveness starts.
Few alerts
If one or more items from below list apply to your plant operations, you should seriously consider VFD solution to reduce the energy consumption of your motor drive:
- The motor rating is oversized compared to the load demand
- The driven load is of quadratic torque type (most fans, pumps or compressors)
- The motor operates significant portion of time at partial load
- The motor often operates during high tariff for electricity
- The efficiency of the motor is far from state-of-the-art technology
- The motor is reaching end of its lifetime
- The motor has low power factor (e.g. less than 0.9)
- The utility requires reactive power compensation or applies penalty for low power factor
- The load can benefit from variable speed (apart from energy savings)
- The motor has high starting current causing voltage sags
- The process can be better automated using a VFD
The more points apply to your operations the larger the motivation for a VFD shall be. As a minimum, it is worth to explore such cases in detail. The energy saving study then answers the question whether the utilization of a VFD makes sense or not.
Remember: Time is money. The earlier you start reducing your energy bill the better for your company.
References
[1] Time to evaluate the energy and cost saving potential, https://mb-drive-services.com/time-to-evaluate-the-energy-and-cost-saving-potential/
[2] Energy savings in pump systems: Case study 1, https://mb-drive-services.com/case-study-energy-savings-in-pump-systems/
[3] Energy savings in fan systems, https://mb-drive-services.com/case-study-for-a-fan-system/
