With one of the world’s largest refueling centers for CNG, and government rebates for greener cars (GVRs), gas supplier Union Energy has pumped $1 million (SGD) into the CNG market. The city-state has more than 500 CNG taxis, and is expected to expand to another 2000 over the next two years. Estimates say the city-state already has more than 3000 CNG vehicles. Hybrid cars have gained recent popularity too, with close to 2100 cars on the island, but they are more expensive. Analyists are predicting another ten refueling stations need to be set up to accomodate a projected 30,000 new CNG cars in the future. Singapore’s population is just over 4.6 million.