In the wake of falling energy prices, both the Shell (LSE:SHEL) and BP (LSE:BP.) share prices have taken a tumble in recent times.

A barrel of Brent crude is currently (15 November) changing hands for around $71.50, approximately 22% less than in April. Although wholesale gas prices have been a bit more stable, they’re now 85% lower than when they spiked in January.

Cheaper energy has led to the Shell share price falling 10% over the past six months. BP’s is down 23%.

But which is the best deal? I’m going to look at three popular measures to come up with my own opinion.

1. Price-to-book (P/B) ratio

At 30 September, Shell had a book value of $189.5bn (£149.5bn using the current dollar-sterling…