World Environment Day - the positive impact of VFDs in cutting emissions and energy use

As we mark World Environment Day (5 June 2021) it’s a pertinent time to understand how Invertek Drives’ Optidrive variable frequency drive (VFD) technology is helping reduce carbon emissions and energy use in industries throughout the world.

Increasing energy costs and stricter government legislation to cut CO2 emissions are forcing manufacturers to implement systems that make their processes more efficient.

Globally, industry accounts for more than half of energy consumption together with commercial buildings. Electric motors are the largest single user of electricity accounting for 40% of global electricity consumption.

In the EU, around eight billion electric motors consume nearly 50% of the electricity produced in the region. In July 2021 current EU regulation on electric motors and variable frequency drives (VFD) will be replaced with new and even more stringent regulation.

VFDs help to significantly reduce carbon emissions and energy

VFD technology is making a significant impact in cutting carbon emissions worldwide through accurate and efficient control of electric motors. In some cases, reducing energy costs by up to 50%.

The drives are used in applications from processing and manufacturing to HVAC building systems. These include water pump systems.

One example is an Italian industrial automation control systems supplier who has significantly cut energy costs in the use of industrial shredders.

High electrical absorption was being created on the start-up of the shredder by an existing Star/Delta starter. This, combined with a lack of motor speed control, was creating high energy costs and wear on the blades of the shredder.

Gas Automazioni s.r.l. (GAS s.r.l) and Omer Ecology s.r.l., an Italian OEM in shredder manufacturing, decided to change the existing main line fed Star/Delta starter with a high-performance drive.

“The motor control was a particular issue as this meant the speed of the cutting blades couldn’t be adjusted to match the type of material being shredded. This resulted in wear and damage to the blades. As a result, they needed to be regularly repaired or replaced,” said Stiven Gheller of GAS s.r.l. “This was impacting on the overall efficiency of the plant.”

They used an Optidrive P2 produced by Invertek Drives. The drive is capable of up to 200% torque from zero speed which provides accurate speed control under all load conditions, making it ideal for such an application. The drive used was a three-phase, 250kW, 350HP, 450Amps VFD to control a 160kW, 300A motor.

Accurate motor control reduced energy use

“Straight away we were able to accurately control the speed of the motor, resulting in reduced energy use. We shredded a range of materials and there was immediately much less wear or damage,” added Manuel Meneghelli, Area Manager at Invertek Drives Italia.

“Just as importantly, the previous high absorption resulting from Star/Delta starter was reduced, cutting energy costs for the plant.”

This single application demonstrates how VFD technology can reduce energy and running costs and, if reproduced in other electric motor-controlled applications, can impact on the need to reduce global energy usage and cut emissions.

In larger-scale applications the impact is even greater.

25% reduction in energy costs with Optidrive Eco VFDs

For example, in Sri Lanka nearly 50% of the energy consumption in the country’s tea-producing industry is through the withering process - the method used for drying tea leaves.

The introduction of VFD technology has seen a cut in energy costs of between 20-25%.

In 2018 hundreds of drives were installed and commissioned in many tea plantations throughout the country as part of NAMA, a project, led by the Sri Lanka Sustainable Energy Authority, under the direction of the Ministry of Power and Renewable Energy, and the United Nations Development Programme, to reduce greenhouse gas emissions through greater efficiencies.

Tea withering uses fans to remove moisture from the black tea leaves, drying them up to 40 or 50% during a 12 to 18-hour period.

Previously, fans would run at a constant speed blowing air through dampers to dry the leaves. The dampers would be manually controlled to adjust the airflow.

The withering troughs had been using DOL or Star/Delta Starters to start fans and use dampers to control the airflow to obtain the withering of tea leaf in the existing system.

The introduction of the drives meant the airflow could be controlled more accurately and efficiently by varying the fan speed rather than adjusting the dampers. This considerably reduced energy usage.

Invertek Drives were involved in the project with Hayleys Aventura Pvt. Ltd. They used an IP66 / NEMA4X rated drive enclosure due to the harsh conditions involved in the process.

Tea manufacturers have said the introduction of the VFDs has not only reduced energy costs but increased the quality of the tea leaves.

VFDs are also being introduced to other parts of the tea manufacturing process, including controlling furnaces and the amount of energy they produce.

For more media information, contact:
Owain Betts, PR, Media and Communications
t: +44 (0)1938 558 253
m: +44 (0)7787 437 052