Coal miners; coal seams; coal haulers.

煤矿工；煤层；运煤工。

Heavy haulers are especially good testbeds because they're large enough to carry the pumps and tanks the system needs to run.

重型货车是特别不错的实验台，因为这些车辆能携带系统需要运行的汽油加油泵和油箱。

Reducing truck idling helps to improve air quality and conserve fuel, saving money for long-haulers already faced with rising diesel prices.

卡车发动机不再空转，这大大改善空气品质，又节省能源，为运输业者省下大笔油费支出。