The main advantages of using diesel driven electrical power generators are (not in rank order):
1. Performance. Diesel engines normally have high thermal efﬁciencies, in the region of 40% and higher, almost regardless of their size. Some current state-of-the-art engines can achieve efﬁciencies over 50%, and engine manufacturers have forecast efﬁciencies as high as 60% by the twenty-ﬁrst century.
2. Maintenance. Diesels represent mature and well-developed technology and are comparatively easy to maintain on site without the need for fully skilled personnel except for certain nonroutine tasks.
3. Durability and Reliability. Diesels have long lifetimes in the range, on average, of at least 20 to 25 years, and they can operate 7000 to 8000 h per year and in some cases up to 12,000 h between regular major overhauls.
4. Fuel Efﬁciency. In most power-generation applications, diesels have the most competitive fuel consumption rates, and between half-load and full-load their fuel consumption rate is reasonably constant. Depending upon the application, size of engine, loading, and the operating environment, diesel engines normally have a speciﬁc fuel consumption in the range 160 to 360 g/kWh. The new Sulzer Diesel RTA two-stroke engines are claimed to be able to produce up to 35,431 kW (47,520 bhp) with a speciﬁc fuel consumption as low as 154 g/kWh (115 g/bhp).
5. Transportability. Diesel-generators can be transported on purpose-built trucks or in specially equipped containers by land, sea, or air so that they can be used immediately on arriving on-site even in remote areas. For their physical weight and size, they can generate large amounts of electrical energy, sufficient to supply a small town.
6. Cost. The cost per unit power installed is very competitive, but it must be emphasized that in costing diesel-power generation it is crucial to determine the total installed costs, not simply the capital cost of the engine and the generator. As a general rule of thumb, the speed of crankshaft rotation basically determines the weight, size, and cost of an engine in relation to its output power.
7. Operational Flexibility. Diesels can use a wide variety of fuel quality and can be designed to use both liquid and gaseous fuels; that is, they are ‘‘dual–fuel’’ engines. They can also be adopted for use in cogeneration and total-energy systems and in ‘‘non-air’’ environments.
8. Environmentally Compliant. Diesels inherently produce low amounts of harmful exhaust emissions. However, in recent years, engines have had to be redesigned and exhaust-emissions treatment systems upgraded to meet increasingly stringent regulations. It is certain that further advances in the efﬁcacy of emission reduction techniques will be required for all fossil-fuel power systems in the future.