The present paper attempted to forecast demand for primary energy broadly categorized into: (a) commercial (coal, petroleum, natural gas, and hydropower), and (b) non-commercial energy (rice hull and straw, jute stick, firewood, crop wastes, etc.) for the period 1992/93-2019/20 AD to facilitate in energy sector planning and development. Demand forecast, based on past time series data (1972/73-1991/92), is made by utilizing two methods: (a) "Market Penetration Theory" that uses trend extrapolation and inter-fuel substitution principles, and (b) "Trend Extrapolation Model" taking into account the exogenous variables, e.g., GDP and energy/GDP ratio. Results reveal that fractional share of commercial energy in total energy consumption will increase from 51 percent in 1991/92 to 85 percent by 2019/20 AD. Total primary energy demand for 2019/20 AD, by using "Market Penetration" model, is estimated at 1,465 PJ. The share of commercial and noncommercial energy constitutes 1,239 and 226 PJ, respectively. The annual compound growth rates for total energy, commercial energy and non-commercial energy for the period 1992/93-2019/20 AD is estimated at 3.23, 4.89 and -0.84 percent, respectively. This implies that commercial energy demand would increase four fold from its 1991/92 consumption level of 300 PJ while demand for noncommercial energy, being substituted by commercial energy over time, would decrease slightly instead. Within the commercial energy sector, demand for natural gas would dramatically increase six folds covering 97 percent of total commercial energy demand. Therefore, special attention is required to plan for commercial energy sector as it relates to direct depletion of a non-renewable natural resource stock, the natural gas. Energy demand forecasts made by utilizing "Trend Extrapolation" model also yielded a close estimate of total energy demand of 1,655 PJ by 2019/20 AD (a 13 percent variation from the estimate of "Market Penetration" model).