Interview with Deepak Pohekar: Executive Director, ZF Wind Power Coimbatore Pvt. Ltd

Executive Director, ZF Wind Power Coimbatore Pvt. Ltd

ZF Wind Power is a globally established designer, manufacturer and supplier of advanced gearbox solutions, supplying major manufacturers of gear-driven wind turbines. Headquartered in Lommel, the company has a global footprint with manufacturing and service facilities in Belgium, Germany, India, China and the US. ZF Wind Power Coimbatore (India) has a state-of-the-art manufacturing plant, fully integrated wind turbine gearbox manufacturing facility supplying for India and global wind turbine requirements. In an interview with Renewable Watch, Deepak Pohekar, Executive Director, ZF Wind Power Coimbatore Private Limited talks about the company’s product offerings, emerging opportunities in the wind power space and the key technology trends. He also shares the company’s short-term and long-term goals.

What are ZF Wind Power’s various offerings? What is the company’s geographical reach?

ZF Wind Power empowers a sustainable future by closely working with its business partners to improve the efficiencies in wind supply chain. It is strategically located across the world with multiple manufacturing and service facilities in Europe, India and China. The company designs its products globally with engineering centres close to the customers and the market.

ZF Wind Power also offers service support across globe with its service staff, distribution centres and authorised service agencies.

It designs customised and modular gearbox platforms with focus on its SHIFT platforms (for example, SHIFT 3k, SHIFT 4k, SHIFT 6k, SHIFT 7k). The later generation platforms are designed for efficient torque conversion and upgradeability suited to different wind conditions.

What is your take on the emerging opportunities in the wind power space especially with respect to hybrids and repowering? 

Wind-solar hybrids are catching up as a technology to harness “best of both worlds” from wind and solar power. Due to the temporal differences in the efficiency of both the technologies, they complement each other to improve asset utilisation and LCOE.

Repowering is a market that is emerging worldwide and will become increasingly important as aging turbines in a good wind location can be upgraded or completely replaced with more efficient technology that harvests more annual energy per land area. Repowering markets are growing in the US and now in Europe as well. We expect a repowering market to emerge in India as well, generating additional demand of 1.5-2GW of new installations by 2030.

What are the key innovations that ZF Wind Power is focusing on? 

Modularity: ZF Wind Power is the pioneer of the ‘modular platform approach’. In order to compete in different onshore market segments – with different requirements – OEMs continue to introduce turbine designs with optimized LCOE, by reducing costs and boosting annual energy production. As a result, wind turbines for the onshore wind market get segmented into an increasing number of torque segments. Therefore, ZF shifted its designs to a modular gearbox architecture that anticipates the growing number of torque segments: SHIFT. The modular platform structure provides greater flexibility in new turbine development and allows further optimization potential over the turbine’s lifetime. The entire modular SHIFT platform is extended across different torque ranges, from 3k (3,000‑4,000 kNm) over to 4k and 6k, and even up to 7k (7,000‑8,000 kNm). Each ‘xk’ platform of gearboxes is designed for a predefined market segment in terms of prevailing wind speeds and thus needed power ranges and capacity factors. The platform designs are also driven by logistical constraints and the interchangeability of components within each ‘xk’ platform is taken into consideration. This drives the torque positioning per platform as well as the lower and upper ratio limit. Keeping the gear unit interfaces and outer dimensions identical across the torque range of an ‘xk’ platform eliminates the need for major drive train/nacelle redesigns over the lifetime of the wind turbine platform.

A new modular gearbox platform is typically launched in one manufacturing location, and then extended to a second or third location if the market requires. This makes SHIFT a truly global platform, with quality levels independent of its manufacturing location, and a supply chain optimized for local markets and best cost.

Torque Density level: Reaching a torque density level of 200 Nm/kg is a gradual approach that requires a combination of technological elements: most obviously, the number of gear stages and the number of planet gears in the planetary stages, as well as the right choice of bearings. Depending on the torque level, the cost of the optimum number of planets in a planetary stage can vary. However, it’s safe to say that more than 5 planets will typically be used for high-torque machines in at least the first stage of the gearbox in the future. Depending on the required outer diameter of the gearbox, roller bearing solutions can still lead to competitive torque density levels. But journal bearings make it possible to build gearboxes with smaller outer diameters and thus reach higher torque density levels.

Optimal load distribution across the different planets becomes an issue as the number of planets in the gear stages increases. Typically, loads are unevenly distributed to a certain extent. However, ZF Wind Power manages to arrive at a close-to-optimal load balance between the planets. This is achieved by a smart combination of advanced simulation models and use of production data. The simulation models take all flexibilities and deformations of the system into account, while the data models take the spread on tolerances in the chain of components (gears, shafts, and bearings) into account. ZF Wind Power will continue to invest in a combination of system analysis, data analysis, and consequent implementation in smart production processes to reach improved torque density and reliability.

Powertrain: ZF Wind Power foresees future opportunities to improve LCOE by way of better integration of different turbine components. In this direction, ZF Wind Power already manufactures complete powertrains for certain applications and intends to improve its capabilities in this area.

What is your take on the increasing role of digital tools in the wind power space?

ZF Wind Power helps IPPs and OEMs to utilise digitalisation efforts to improve predictive maintenance activities and thereby increasing turbine energy output. State-of-the-art analytics combine data from gearbox manufacturing and life cycle monitoring with advanced reliability models to reduce the levelized cost of energy.

Through its advanced services ZF Wind Power is directly supporting partners to reduce the operational costs and increase the energy output of wind turbines. With processes in place to capture, store and process data, we enable the lifetime extension potential of the gearbox. The company enables its partners to increase energy production and avoid unscheduled downtime by early anomaly detection, pro-active planning of repairs and guaranteeing availability of spare parts and field service technicians.  Further, the company supports to unlock insights of gearbox lifetime extension potential and load increase potential.

Operating costs to manage the turbine are greatly reduced through the digitalization services. Thanks to early anomaly detection, wind farms are able to avoid consequential serious damages and also have up tower repairs as opposed to cost associated with a crane and gearbox exchange. Through predictive analytics of a gearbox and its remaining lifetime, windfarm operators are able to better manage their inventory, significantly reducing their operational costs.

The company is in the process of implementing pilot projects in the world including India and already sees the benefits flowing in.  ZF Wind Power Coimbatore continues to support the IPPs in India and Asia Pacific to improve their turbine availability and output. India Service Centre can be contacted for such services.

What are the company’s short-term and long-term goals? Do you think India’s energy transition ambitions are achievable?

ZF Wind Power is focussed on empowering a sustainable future by its products as well as in its operations. It intends to utilise 100% electricity use in all its operations from renewable sources by 2030 and support to reach climate neutral by 2040. The company will continue to maintain its market leadership position by continuing investment in technology development and supporting the customers globally.
Government of India has set an ambitious energy transition goal and ZF Wind Power as responsible global corporate will earnestly support in achieving the same.