Real Options in DCF

Step 1: Expansion Option Payoff at Year 3

Option Payoff = MAX($40.0m − $15.0m, 0) = MAX($25.0m, 0) = $25.0m

This mirrors the payoff structure of a call option: the company only exercises the expansion if the incremental value it unlocks exceeds the cost of exercising (the additional investment). If the incremental PV had come in below $15.0m, the payoff would simply be $0 — management would walk away rather than lose money.

Step 2: Expected Option Value (Probability-Weighted)

Expected Option Value = (0.60 × $25.0m) + (0.40 × $0m) = $15.0m + $0m = $15.0m

This is the core mechanic of decision-tree-based real options analysis: instead of assuming the option is always exercised, you weight the payoff by the probability that conditions actually turn out favorably. This is what a static DCF cannot capture — it typically forecasts a single expected cash flow path rather than pricing in the asymmetry that management can walk away from the downside.

Step 3: Present Value of the Real Option

Where: r = discount rate, n = number of years until the option can be exercised.

Using the discount rate (10%) and the exercise date (Year 3):

PV of Real Option = $15.0m / (1.10)^3 = $15.0m / 1.331 = $11.27m

Discounting brings the expected option value back to today's dollars, consistent with how the rest of the DCF is valued. Analysts sometimes use a lower discount rate for the option leg specifically (closer to risk-free) because the option payoff is contingent rather than as risky as the base business cash flows — for this case, the same project discount rate is used for simplicity.

Step 4: Total Project Value with Optionality

Total Project Value = -$5.0m + $11.27m = $6.27m

This is the key takeaway: the static DCF alone signals a value-destroying project (-$5.0m NPV) and would get rejected in a simple screen. Once the expansion option is priced in, the project is actually value-creating (+$6.27m). This is exactly why acquirers, biotech investors, and natural-resource companies routinely pay more than a plain DCF implies — they are paying for embedded flexibility, not just for the base-case cash flows.

Final Results

• Base Project NPV (Static DCF): -$5.0m
• PV of Expansion Option: $11.27m
• Total Project Value (with Optionality): $6.27m

This total project value is what should actually go into the investment committee memo and the go/no-go decision — not the static DCF figure alone, since it understates what the business is worth by ignoring management's flexibility to act on good news.

Would you like to explore how the option value changes if the probability of favorable conditions were lower, say 30%, or if management also had the option to abandon the project entirely after Year 1?