BMW cars with roof-mounted solar panels could be one of the features that future cars from the company could include. The effort behind the solar roof is to save fuel costs and cut pollutants. The functions of the solar panel could include topping up the car's battery or even pre-warming liquids in the engine to make cold starts less wearing on mechanical parts and also more fuel-efficient. Another use could be pre-warming air-conditioning systems. The solar panels were showcased on a BMW X5 diesel hybrid SUV (Sports Utility Vehicle) at the Geneva Show earlier this year. Apparently a square meter of solar paneling is capable enough of generating enough electrical power to run or charge up onboard systems such as navigation devices and cell phones.
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