Diesel generators (DGs) are used across industries as a viable alternative to grid power for supporting operational needs. In recent years, there have been significant technological advancements in DG sets, aimed at minimising noise, controlling emissions, and enhancing power output and efficiency. Various innovative technologies have been introduced to render gensets more compact and adaptable to extreme climatic conditions. Notably, electronic control systems are emerging as a key trend in the DG space, facilitating remote monitoring of systems for improved efficiency and management. Further, in response to evolving challenges, manufacturers of DG sets are actively embracing the latest technologies to introduce models that adhere to the most recent emission standards. Recently launched generator variants are now capable of seamlessly integrating battery energy storage systems and solar power with DG sets, offering consumers a cleaner power supply. Moreover, there is a heightened emphasis on dual-fuel gensets capable of operating on both natural gas and diesel. The adoption of smart diesel engines represents a notable technology trend, leveraging digital solutions for operational control, load distribution and optimised combustion.
Power Line explores key technological developments in diesel engines and gensets…
Hybrid/Multifuel technology
Hybrid and multifuel technologies have become integral solutions for captive power plants, offering improved system reliability, enhanced efficiency and substantial cost savings. Innovative hybrid/multifuel generators combine traditional diesel gensets with renewable energy sources such as solar, wind and biomass, ensuring dependability, economic benefits and compliance with environmental standards. These systems, incorporating at least two different energy sources, often combine solar photovoltaic (PV) and diesel engines, while multifuel technologies enable interchangeability between biomass feedstock and coal. A solar PV-diesel hybrid system is designed to optimise the PV system’s load, while minimising reliance on the DG set. In instances where the PV array generates sufficient power, some gensets can be completely shut down. Systems equipped with batteries allow gensets to recharge batteries when necessary, ensuring uninterrupted power supply. The scalability of these systems, ranging from kilowatts to megawatts, allows for easy expansion based on requirements and configurations, tailored to specific factors such as load demands, location and solar radiation levels.
Storage batteries represent an emerging technology in the hybrid genset space, charged by renewable power sources and fuel generators during operation. While the initial incorporation of battery storage in diesel-solar hybrid systems involves higher capital expenditures, it proves cost-effective over the system’s life cycle by enhancing operational efficiency. Hybrid generators find application in challenging locations with limited access to fuels, offering prolonged operation with reduced fuel consumption. Additionally, their compact design makes them suitable for areas with size and weight constraints, facilitating easy transportation.
Natural gas gensets
Natural gas gensets offer a cleaner and more efficient alternative to diesel-based gensets, with significant advantages such as lower emissions, reduced operational costs and lower maintenance requirements. These gensets are quieter, operate at lower temperatures and have fewer moving parts compared to their diesel counterparts. The ecological benefits of burning natural gas include lower emissions of sulphur, nitrogen and carbon oxide, aligning well with environmental regulations. They are increasingly being adopted in Delhi, Gujarat and Maharashtra, where natural gas is readily available through pipelines. Natural gas gensets also stand out as economical, with lower operating costs and installation expenses as well as cheaper fuel, compared to other non-renewable sources. The total cost of ownership for natural gas gensets is estimated to be around 40 per cent lower than that of diesel gensets. Paralleling generators over time provides flexibility and cost advantages, allowing for a distributed approach with built-in redundancy.
Smart DGs
Smart DG sets featuring digital controls, in contrast to conventional analogue systems, offer enhanced performance, efficiency and reliability for diesel engines and gensets. These digital control systems provide real-time monitoring of various engine parameters, including fuel levels, engine oil, coolant, temperature, battery status and transfer switch status. Connected to computers, they enable remote monitoring, real-time fault diagnostics and corrections, saving space with integrated functions compared to separate control modules in analogue systems. These smart DG sets contribute to stable voltage and improved output frequency by automatically adjusting fuel rate input and injection timing under diverse load conditions. Consumers are increasingly favouring IoT-based smart/digital DG sets, allowing remote monitoring of crucial parameters such as fuel consumption, abnormal noise levels, power generation, capacity utilisation and running hours, among others. Containerised DG sets are also gaining popularity due to their compliance with strict acoustical standards, resistance to high temperatures and adverse weather conditions, and ease of maintenance.
An important application area is the use of digital paralleling solutions. Paralleling gensets is not new and many facilities run several generators in parallel to ensure power reliability and guarantee sufficient emergency or backup power. Paralleling generator systems involves synchronous operation of two or more generator sets connected together on a common bus in order to provide power to common load. Paralleling generators helps improve reliability, increase load management flexibility, manage run time on engines and provide maintenance flexibility, reducing generator costs. With a paralleled generator system in place, additional generator capacity or redundancy can be added as needed. Adding digital controls helps to simplify operating several smaller generators in parallel. Sophisticated electronic controllers help minimise the number of controls, providing an inherently more reliable system. They also integrate paralleling switchgear into the system, so that a third-party switchgear solution is not needed.
Silent diesel gensets
Silent diesel gensets encounter noise primarily during engine start-up, especially as fuel is injected into the pre-chamber and undergoes vaporisation at high temperatures. Recent advancements in sound attenuation technologies have significantly mitigated noise levels. One approach involves incorporating sound attenuation pockets within the prechamber. Strategically spaced and designed, these pockets effectively neutralise detonation waves generated during combustion. Alternatively, these pockets can be filled with porous or metallic ceramic pellets coated with platinum or rhodium, acting as catalysts for complete combustion while simultaneously dampening noise. Additional modifications include the placement of attenuating materials, such as porous ceramic or sintered metal, near the passage connecting the prechamber to the combustion chamber.
Conclusion
In conclusion, the diesel genset segment anticipates significant advancements including engine modifications, fuel system efficiency, digital controls and emission treatments, aligning with stricter requirements. These improvements are poised to enhance the overall performance and reliability of diesel gensets, solidifying their role as a robust power source. Choosing the most suitable technology remains crucial to meet the diverse needs of end-consumers. Looking ahead, the demand for DG sets and diesel engines is expected to stay robust in the short-to medium term, particularly in sectors such as railways, marine, mining, construction and data centres. However, a long-term industry shift is foreseen, driven by the increasing prominence of solar energy and battery storage. As the nation actively works towards its emission reduction target of 1 billion tonnes by 2030, the diesel genset industry is likely to experience disruptive changes in the evolving energy landscape.