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This is no golf cart. This is one of the biggest mining excavators in the world. The clawed bucket it uses for tearing at mineral-laced rock is so big that you could fit more than 3,000 footballs in it. The driver sits in a cab roughly as high up as the roof on an average two-storey British house. And the excavator's hefty caterpillar tracks alone are just shy of 3m (10ft) tall – and about as long as a London bus.
It weighs 778 tonnes in total and you might be forgiven for thinking that this beast, the PC8000-11 surface mining excavator made by Komatsu, could only run on a fossil fuel like diesel. Surely such a behemoth demands all the raw, dirty power of combustion to function? Well, there is a diesel model – but Komatsu have recently brought out an electric equivalent. And it works just the same.
"We are not sacrificing performance when you go electric," says Thomas Jordan, marketing manager at Komatsu Germany. While the diesel excavator guzzles more than 400 litres (88 gallons) of fuel per hour, according to Komatsu, the electric alternative relies instead on a chunky power cable – meaning the vehicle itself produces zero emissions.
When comparing diesel and electric versions of the excavator used by one Swedish customer, well-to-wheel emissions are 95% lower for the electric type, according to Komatsu. This customer has access to electricity from nuclear and hydro sources. Mining companies are increasingly interested in options like this, says Jordan. "We see a trend for more electrification, that's definitely the case."