A tank battery is the surface facility on an oil lease where production from one or more wells is separated, treated, measured, and stored before it leaves for market. The name refers to the group (battery) of storage tanks at its heart. This guide explains what a tank battery is, the equipment it contains, and how it fits in the production chain.
Tank Battery in one line: A tank battery is a group of storage tanks and associated processing equipment on an oil lease where produced fluid is separated into oil, gas, and water, treated to spec, and the oil stored in stock tanks until it is sold or hauled away.
A typical onshore tank battery gathers flow from one or several wells and runs it through a sequence of equipment. A separator splits gas from liquid (and often water from oil). A heater treater dries the oil to sales BS&W spec. The clean oil then flows to the stock tanks - the batteries of storage tanks that give the facility its name - while gas goes to a sales line or flare and produced water goes to a water tank for disposal or reuse.
Supporting equipment rounds out the site: a gas meter or flow computer, pressure and level instruments, dump valves, a vapor recovery unit or thief hatches on the tanks, and often secondary containment (a lined dike or berm) around the tanks to catch spills.
Oil leaves a tank battery one of two ways. Trucking (haul-off) means a driver gauges the tank, takes a sample, and loads oil into a tanker - custody is transferred by tank gauge or ticket. A LACT unit (Lease Automatic Custody Transfer) automates the same handoff for pipeline delivery, measuring volume with a meter, sampling for BS&W, and recording the transfer without a person present.
Either way, the stock tanks are the custody point - the last place the operator controls the oil before ownership changes - so accurate tank levels and volumes are directly tied to revenue and reconciliation.
Because a battery aggregates a whole lease's production, it is a natural place to concentrate monitoring: tank levels, separator and treater conditions, gas meter volumes, dump cycles, and high-level or overflow alarms. Rising tank levels warn that hauling is due; a stuck dump or a treater off temperature shows up quickly.
An RTU or flow computer at the battery reads these signals, and a cloud SCADA such as Merobix polls it over Modbus or DNP3 so tank levels, alarms, and throughput across many batteries are visible from one dashboard - useful when one pumper covers dozens of leases.
It is the surface facility on a lease where production from one or more wells is separated, treated, measured, and stored in a group (battery) of tanks before sale. It typically includes separators, a heater treater, stock tanks, a gas meter, and either trucking access or a LACT unit.
Commonly one or more separators, a heater treater, oil stock tanks and a water tank, a gas meter or flow computer, dump valves and level and pressure instruments, a vapor recovery unit or thief hatches, secondary containment, and either a truck loadout or a LACT unit.
A LACT (Lease Automatic Custody Transfer) unit automates the handoff of oil from a tank battery to a pipeline. It measures volume with a meter, samples for BS&W, and records the custody transfer automatically, replacing manual tank gauging by a person for pipeline delivery.
This page references the protocol specifications published by the organizations below. Editions, product capabilities, and documentation change over time - confirm current requirements and specifications directly with the source.
Last reviewed: July 27, 2026. Merobix is not affiliated with, endorsed by, or sponsored by these organizations; their names are used only to identify the standards and products discussed.
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