Complex sentence: The roof is part of an $18 million rainwater treatment system designed to clean 20 billion gallons (76,000,000 m³) of rainwater annually, this saved Ford $50 million that would otherwise have been spent on mechanical treatment facilities.
Split into simpler sentences: The roof is part of an $18 million rainwater treatment system designed to clean 20 billion gallons (76,000,000 m³) of rainwater annually. This saved Ford $50 million that would otherwise have been spent on mechanical treatment facilities.