An improved unbiased grey model is developed to forecast urban gas supplies to efficiently allocate resources and ensure urban safety. The model uses three-point smoothing and an equal dimension new information model. Comparison of the improved unbiased grey model with the original model to predict the gas supplies indicates that the original model predictions decrease linearly so the differences between the predicted and actual gas supplies increase over time. The improved unbiased grey model gives nonlinear results that are better for mid-to-long term forecasts with the predicted gas supplies in better agreement with actual statistics. The average relative error for gas supplies predicted by the original model is 7.32% while that for the improved model is 5.76%.
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