REG Ralston is a biodiesel production facility in west-central Iowa. REG began operations in the biorefinery in 2002 and upgraded the plant's capacity to 30 million gallons per year in 2018. REG Ralston was the first REG biodiesel plant.
- Nameplate capacity: 30 mmgy
- Feedstocks: Low free fatty acid feedstocks
- Loading capabilities: Truck and rail
- Rail line: Union Pacific
- Production start date: August 2002