The use of low concentration fuel in generator sets is to ensure the safety and efficiency of the combustion process. The following are several reasons:

1. 安全考虑：使用低浓度燃料可以降低爆炸的风险。高浓度燃料容易在系统中形成可燃气体混合物，在某些情况下，如泄漏或故障，容易引发火灾或爆炸。

1. Safety considerations: Using low concentration fuel can reduce the risk of explosion. High concentration fuel can easily form combustible gas mixtures in the system, and in some cases, such as leaks or malfunctions, it can easily cause fires or explosions.

2. 能：低浓度燃料的燃烧速度较快，可以更好地满足大功率输出的要求。此外，燃烧时产生的烟气和污染物也相对较少，有利于环境保护。

2. High efficiency: Low concentration fuel has a faster combustion rate, which can better meet the requirements of high-power output. In addition, the smoke and pollutants generated during combustion are relatively less, which is beneficial for environmental protection.

3. 经济性：低浓度燃料通常价格相对较低，使用低浓度燃料可以降低成本。

3. Economy: Low concentration fuels are usually relatively inexpensive, and using low concentration fuels can reduce costs.

综上所述，使用低浓度燃料的发电机组在安全性、效率和经济性方面都具备优势。这也是为什么许多发电机组选择使用低浓度燃料的原因之一。

In summary, power generation units using low concentration fuels have advantages in terms of safety, efficiency, and economy. This is also one of the reasons why many power generation units choose to use low concentration fuel.