Backed by more than 20 years of development in not only mining, but also industrial and military applications, Howden offers advanced ventilation control strategies that not only deliver according to real time air requirements, but also optimise the use of ventilation infrastructure to ensure the minimum consumption of energy possible. The computational engine continuously solves the system of equations of the mine ventilation network in real-time. A simplified example is seen in the comparison of two different operating scenarios on a mine level in Figure 2. For clarity, Figure 1 shows the 3D configuration of the area seen in Figure 2. This highlights the use of "Speed Optimizer" A proprietary advanced control strategy.
As can be seen both situations deliver the required air for the two occupied working areas. However, for the scenario on the left it can be seen that the work area requiring the most flow has an 80% damper opening, and the fan is operating at a much lesser speed. In fact, by reducing the fan speed by one half, an 88% reduction in power consumption is achieved. The system is thus minimising mine resistance to allow for a reduction of fan speed, all in real time. Once these kinds of optimisations are realised throughout an entire mine, the total air demand of the mine may decrease by more than 30%. This reduction is then considered for the surface fan speeds as well, their speeds are also automatically reduced accordingly, thus generating energy savings of more than 50% mine wide. Fan Law 1 gives us this convenient exponential relationship between fan speeds and power consumption (The proportion of reduction in speed results in a power consumption of that same proportion to the 3rd power).