Valuing Pud Reserves: A Practical Application Of Real Option Techniques

Discounted Cash Flow (DCF) tools are fundamental to engineering and financial analysis in the oil industry, are well understood by managers, and generally provide accurate valuations of developed hydrocarbon reserves. Unfortunately, DCF techniques systematically undervalue proven undeveloped reserves (PUDs), may encourage premature development of certain reserves, and fail to identify important risk management opportunities. Real option valuation models overcome these shortcomings by providing a more complete picture of not only reserve values, but also of the drivers of that value. The authors of this paper collaborated in developing a PUD real option model for a large U.S. E&P company (referred to as “XYZ Petroleum”). Based on an analysis of XYZ's drilling costs and other major inputs over a 12‐year period, the authors show that PUDs are rich sources of option value. In addition to the volatility of oil and gas prices, a somewhat more surprising contributor to option value was the lack of correlation (which came as a surprise to XYZ's managers) between development costs and oil prices. During certain periods, the economic value of a PUD was more than twice the NPV estimated by static DCF techniques. In addition to valuing PUDs and explaining why undeveloped reserves are usually valued at more than their DCF value, the model can also be used to tell managers when is the value‐maximizing time to drill—or, alternatively, how much value is likely to be forfeited if managers choose to drill too soon.