The problem with turbines is that it has a very narrow powerband, as far as engine speed is concerned. Not advisable with stip and go traffic. Once in the powerband it's a very efficient engine, but like I said it's a very narrow rpm band. Off the powerband, I wouldn't be surprised that efficiency would be half of a wankel engine.
Another problem is when they want to keep it on the powerband while the vehicle is stationary, then it has to be kept at the optimum rpm, eating fuel and a noisy engine even at a standstill. It could charge the battery efficiently, but what happens if the battery is fully charged? You can't just stop the turbine, it would take time for the rpm to build up to optimum operating speed. The internal combustion piston engine is still a better choice when you want engine speed to vary quickly.
Happy New Year!!!
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