What is a benefit of decreased mine resistance when increased air circulation is not necessary?

Decreased mine resistance can lead to several benefits, particularly in relation to fan operation and energy consumption. When the resistance is lower, the workload on fans is reduced. This means that fans do not have to work as hard to push air through the mine, allowing for a reduction in fan speed without compromising airflow or ventilation effectiveness.

By reducing fan speed, a significant amount of energy can be conserved. Fans are powered by motors that consume electricity based on the speed and load at which they operate. When fan speed is decreased, it not only reduces the energy consumption directly related to the fan operation but can also minimize wear and tear on the fan system, potentially leading to lower maintenance costs over time. This connection between reduced fan speed and power savings illustrates a key principle in mine ventilation management, where efficiency can be maximized by analyzing mine resistance and adjusting operational parameters accordingly.

The other options do not align with the context of decreased mine resistance; for instance, increasing fan speed typically leads to higher power consumption rather than savings. Similarly, while efficiency of machinery may improve indirectly due to better airflow, it is not a direct benefit of simply decreasing mine resistance.