 The propulsion consisted of four Parsons steam turbines , each of which was housed in a separate engine @-@ room . The turbines were powered by twelve Babcock & Wilcox boilers . The turbines were designed to produce a total of 27 @,@ 000 shaft horsepower ( 20 @,@ 134 kW ) , which was theoretically enough to attain her designed speed of 20 knots ( 23 mph ; 37 km / h ) , but no figures from her speed trials are known to exist . She carried 1 @,@ 844 @.@ 5 tonnes ( 1 @,@ 815 @.@ 4 long tons ) of coal , and an additional 267 @.@ 2 tonnes ( 263 @.@ 0 long tons ) of fuel oil that was to be sprayed on the coal to increase its burn rate . At full capacity , she could steam for 4 @,@ 200 nautical miles ( 7 @,@ 800 km ) at a speed of 10 knots ( 12 mph ; 19 km / h ) . 
