VI Energy Politics & Supply Security
Shut-in production
Supply lost when an oil or gas well that is able to produce is temporarily closed for maintenance, repair or lack of access to markets.
How it works
The US Energy Information Administration (EIA) glossary defines shut-in as temporarily closed: wells and mines capable of producing may be closed for repair, cleaning or lack of market access. The key point is that the well keeps its ability to produce. What stops is the flow, not the capacity.
In a war or blockade, the mechanism runs through storage. Once exports stop, crude first fills onshore tanks and tankers; when storage is full, the producer has to shut in wells. A 2026 analysis by Columbia University's CGEP wrote that an Iran with near-zero exports might have to cut output to as little as half its pre-war level to avoid filling its storage.
The measurement trap is that shut-in output may not come back as fast as it went offline. Restarts bring problems with paraffin, asphaltenes, scale and water cut; in mature fields, pressure loss and water encroachment can cause permanent losses. In 2026 CGEP projected that about 70% of Iran's output could return quickly, with the rest taking months.
Why it matters here
In a supply shock, the market assumes shut-in barrels return as soon as a deal is struck. In fact, how fast shut-in output comes back depends on the reservoir, storage and the fleet, and that speed decides how far a peace scenario can push prices down. In a months-long disruption like Hormuz, the gap between headline capacity and the supply that can really return is where the next pricing error comes from.