Duke Energy Corp (DUK) is slightly undervalued and National Grid Plc ADR (NGG) is overvalued.
Against our estimates of intrinsic value, DUK trades at the wider discount: a margin of safety of +14%, against -21% for NGG.
Values as of the 22 Sept 2026 close.
Discounting its cash flows at 6.9% (average of 2 methods) values the shares at $135.16; the price of $116.31 is 14% below that value, and 83% of that value comes from beyond year five.
Leak Score 48/100 on 10 of 12 signals
Discounting its cash flows at 7.3% (average of 3 methods) values the shares at $63.55; the price of $76.86 is 21% above that value, and 82% of that value comes from beyond year five.
Leak Score 14/100 on 3 of 12 signals
| Metric | DUK | NGG |
|---|---|---|
| Verdict | Slightly undervalued | Overvalued |
| Price | $116.31 | $76.86 |
| Intrinsic value | $135.16 | $63.55 |
| Margin of safety | +14% | -21% |
| Leak Score | 48/100 (10/12) | 14/100 (3/12) |
| Market cap | $90.7B | $77.3B |
| Revenue growth, 5 years | 6.2% | 5.8% |
| Operating margin | 26.6% | 28.5% |
| Net margin | 15.6% | 18.3% |
| Return on equity | 9.9% | 8.6% |
| Debt to equity | 1.68 | 1.19 |
| P/E | 17.4x | 17.6x |
| Forward P/E | 16.2x | 11.7x |
| P/B | 1.7x | 1.5x |
| Dividend yield | 3.8% | 4.3% |