Invertek helps brew up efficiencies in Sri Lanka’s tea industry

UK-based Invertek Drives is helping create significant efficiencies and savings in the world’s fourth largest tea producing country as part of a project to reduce greenhouse gas emissions. Invertek, one of the world’s leading designers and manufacturers of variable frequency drives (VFD), is supplying 200 of its Optidrive Eco drives in the first phase of a tea withering project in Sri Lanka through sales partner Hayleys Aventura Pvt. Ltd.

One of the objectives of the multimillion-dollar project is to make the tea withering process of Sri Lanka’s tea industry more efficient and to reduce its impact on the environment.

The project, led by the Sri Lanka Sustainable Energy Authority, under the direction of the Ministry of Power and Renewable Energy and United Nations Development Programme in Sri Lanka, aims to reduce greenhouse gas emissions from the energy sector by developing a NAMA framework, with the objective of supporting appropriate climate change mitigation actions in country. The project is financially supported by the Global Environment Facility.

In total, the project will facilitate the implementation of 1,000 bio-digesters, and 1,000 variable frequency drives in tea factories throughout the country, as well as the use of photovoltaic technology.

“Tea production is a major industry in Sri Lanka employing over one million people and accounting for three per cent of the country’s GDP,” said Nick Thorne, Invertek’s sales manager responsible for Sri Lanka.

“Each tea withering trough uses large amounts of energy to drive a motor powering fans that aerate the tea leaves to remove the moisture of tea leaf, drying them by up to 40 to 50 per cent over a 12 to 18 hour period. By replacing the existing starters, combined with the efficiencies delivered through the Optidrive Eco, the amount of energy used will be reduced dramatically.”

The Optidrive Eco VFDs provide optimised speed control of the fan motors used, ensuring greater efficiency that minimises energy usage and thus cuts overall CO2 emissions locally and throughout the energy chain.

The Optidrive Eco drives, being installed and commissioned by Hayleys Aventura Pvt. Ltd., Sri Lanka, will help create energy savings of 20 to 25 per cent.

“Quality of the produced tea will mainly depend on the withering process. Withering troughs use DOL or Star/Delta Starters to start its fan and use dampers to control the air flow to obtain the withering of tea leaf in the existing system,” said Anushka Chandrasoma, Assistant Manager, Hayleys Aventura Pvt. Ltd.

“While replacing the traditional starter with VFDs, operators can control the air-flow by reducing the fan speed through a VFD, which enables savings of around 20-25  per cent of the energy used in the withering process. We used Optidrive Eco VFD’s with IP66 enclosures, which have the maximum protection against the dust and the water.”

The Sri Lankan government’s Renewable Energy Resource Development Plan aims to increase the use of renewable energy and decrease the amount of greenhouse gas emissions by 20 per cent by 2020.

Dylan Davies, Invertek’s Product Manager, said the Optidrive Eco range was perfect for the tea project because of its ability to control motors efficiently.

“The Optidrive Eco’s advanced onboard features also mean there is no need for peripheral equipment, reducing costs and the need for additional space. It also provides intelligent maintenance interval timing that allows maintenance reminders, reducing the need for costly downtime in production,” said Dylan.

“With its motor current monitoring function, it also means that any faults in the motors are identified early, again reducing any potential downtime that could affect the aeration of the tea leaves.”

With the Eco’s built-in keypad and OLED text display, commissioning takes just minutes, and ongoing operation is easily managed. It can also be used with Invertek’s new OptiStick Smart that allows Bluetooth access through the OptiTools studio software or OptiTools Mobile phone app.

The Eco range offers third-generation fan and pump control using a series of market-leading innovations, including compliance with the latest harmonic standards and the ability to control a wide range of IE2, IE3 and IE4 motors including AC Induction (IM) Motors, AC Permanent Magnet (PM) Motors, Brushless DC (BLDC) Motors and Synchronous Reluctance (SynRM) Motors.

Installation of the drives is being undertaken at 38 sites throughout Sri Lanka has been completed and commissioned by April according to the guidelines given by the UNDP technical team.

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