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Large Generators for Continuous Electrical Power

Diesel generators, including large generators, generate electricity by rotating an electric alternator using power from a diesel engine. The combined efficiencies of diesel generators typically fall between 30% and 50%. This efficiency range underscores the effectiveness of diesel generators in converting fuel into electrical power.

Diesel generators fulfil a crucial role as practical and reliable devices where power outages occur. As a source of fossil-fuel-derived electrical energy, diesel generators provide impressive energy efficiency, surpassing that of petrol-powered generators of equivalent capacities. Diesel generators utilise compression heat as opposed to spark ignition, which contributes to a remarkable 50% increase in energy efficiency, making generators powered with diesel an environmentally conscious and economically efficient choice for backup power generation.

It is estimated that the South African Diesel Generator market size was in the region of USD 107.52 million in 2022. Projections suggest that the South African Diesel Generator market will grow at a compound annual growth rate of 5.6%, reaching a value of USD 157.45 million by 2029. Growth is driven primarily by frequent power outages, which hamper economic activity, as well as the rising number of data centres due to growing digitalisation. Datacentres require sophisticated backup power solutions and diesel generators form the backbone of these power continuity solutions. Power interruptions, even for short durations, result in considerable economic losses and may even cause damage to sensitive electronic equipment.

 

Large Generators and Renewable Energy

Although solar and wind generation have been on a steep downward cost curve for the last decade and are becoming increasingly more cost-effective alternative sources of electrical power, large generators are still the solution of choice for most companies. The higher the capacity required, the more this holds true. The need for commercial and industrial generators in South Africa is easy to understand against a background of ongoing power outages, both scheduled (load-shedding) and those caused by equipment failure. Losses to South African businesses due to scheduled power cuts alone are estimated to amount to roughly one billion rand per load-shedding stage, per day. There is considerable pressure, both operational and financial, on commercial and industrial entities to provide backup power to mitigate these losses. Size for size, diesel generators are less costly than renewable energy solutions to install. Diesel generators can be deployed relatively rapidly compared to renewables, and diesel generators provide continuous power. Many renewable energy sources suffer from intermittency. The sun doesn’t always shine, and the wind doesn’t always blow, for instance.

 

Large Generators are a Specialist Field

The acquisition of a large generator that wasn’t an operational requirement was, until relatively recently, considered a “grudge purchase”. This is changing as commercial and industrial enterprises realise that providing backup power has become part of the cost of doing business. As the probability of an improvement in grid reliability becomes more and more unlikely, companies find themselves compelled to invest in large generators. Having come to the realisation that a large generator is a necessity, the critical question arises: “Who can you rely on to provide the correct solution for your specific requirement?” Given the substantial capital involved in procuring a large generator, getting it right the first time is crucial.

Generators, while conceptually straightforward, require specialist knowledge and practical experience. The larger the generator, the more demanding the design and installation requirements become. Specifying large generators not only necessitates addressing fundamental questions, such as determining the appropriate size, but also demands a wealth of experience and a high degree of technical expertise to avoid potential pitfalls.

Industries that rely on a large number of electric motors to run various processes in their facilities can be particularly challenging technically. Electric motors can use over six times their rated run capacity for short durations on startup. Mitigating the negative effects of the spikes in demand created when these motors start can be difficult. Steps commonly taken include installing variable speed drives (VSDs) and other “soft start” devices.

The unintended consequence of fitting these devices is the possibility of creating harmonics that stress the electrical network and potentially damage electrical equipment. Poor harmonics may cause electrical infrastructure, such as transformers, motors, and cables to overheat and cause nuisance tripping or damage to digital controllers.

Adding an incorrectly specified large generator to the electrical system will often make matters worse. Experienced and competent large generator suppliers know how to deal with these issues. For example, large generators can be specified and supplied with permanent magnets or auxiliary windings to provide the genset with up to three times it’s nominal current capacity to cover inrush peaks. A variety of advanced solutions such as digital automatic voltage regulators (D-AVRs) are available for diesel generators, allowing the genset to be sized for run loads and not the start-up peaks. This substantially improves efficiency and lowers running costs.

 

Not Every Company that Sells Large Generators is a Generator Specialist

The strong demand for large generators that results from Eskom’s inability to provide reliable power has encouraged a host of new companies to enter the generator supply market. Many of these companies do not have the expertise or experience to design and support large generator solutions. This is particularly true with large generators. Sourcing generators from a manufacturer in China or Turkey and importing and marketing them does not make the importer a generator specialist. Importing generators is a logistics and warehousing exercise, which does not equip the logistics company to install functional solutions. The installation of these generators is usually sub-contracted out to third parties. This practice places the end user in a position where there is no longer a single point of responsibility for the solution.

 

Speak to the Industry Leaders

PacB is a long-established genset specialist renowned in the industry as a manufacturer of superior-quality large generators. When it comes to specifying large generators, significant technical knowhow and experience are essential. We will assist with the design and manufacture of any generator, including any control systems required, whether programmable logic controllers (PLCs), Automatic Mains Failure units (AMF’s), or Automatic Transfer Switches (ATSs).

Our team has expert knowledge and experience of all the main controller brands in the industry. We can design and manufacture Synchronous PLC controlled panels for multi-station generator supply over a vast range of system sizes and voltages, including systems in excess of 1000kVA. From residential systems to utility-scale installations, we are known for functional, robust solutions that our technical support teams keep running flawlessly. Take control of your power and contact PacB today.