The Port of Houston Authority has issued a request for proposals for 10 ship-to-shore cranes for its Bayport and Barbours Cut terminals — a tender that lays bare how hard it has become for US port operators to reconcile technical specs, delivery schedules, budgets and federal cybersecurity mandates in a market distorted by tariffs.

The scale is significant: 10 STS cranes in one order, delivered fully erect within 730 days of the purchase order (the RFP also cites 700 days in places). The port specifies ABB for the drive and control system, though it will entertain "alternative Control System Suppliers for consideration." The cranes must arrive pre-wired for a future remote control station, with an option for three remote stations capable of operating any of the 10 cranes, one at a time.

Cyber requirements set a high bar

The specifications embed cybersecurity compliance at their core. Automation and control system suppliers must meet ISA/IEC 62443, the standard for industrial automation and control system security. Both the crane OEM and the control system supplier must build and document a project-specific Information Security Management System under ISO/IEC 27001.

Beyond standards, both parties must document how they conform to US Maritime Advisories and applicable federal law and regulations on crane cybersecurity — including US Coast Guard Maritime Security Directives 105-4 and 105-5. That layer of compliance effectively tests whether non-US OEMs can satisfy Washington's concerns about control systems on American quays.

The tariff problem

Houston has bought all its STS cranes from China's ZPMC since four Konecranes units arrived in 2015, according to WorldCargo News. That loyalty now carries risk. The 100% tariff on STS cranes, currently suspended until November 2026, would make Chinese-built cranes — or cranes from a Chinese OEM built anywhere — prohibitively expensive if reinstated.

The timing quirk sharpens the gamble: tariffs, if owing, fall due only when the cranes land, roughly two years after contract award. Houston says its evaluation will weigh "anticipated total costs," including tariffs and other duties, but predicting duty regimes two years out is close to impossible. The port is effectively asking bidders and its own procurement team to price political risk.

A thin field gets thinner

Past Houston tenders have drawn just two bids, and sometimes only one. This time the port is actively courting a wider field, stating it wants proposals from "as many interested parties as possible."

"We are looking for STS cranes that can meet our operational and financial needs, so we encourage your firm to submit a proposal even if it does not meet our specifications if it is a viable alternative we should consider," the RFP states — an unusually flexible posture that suggests Houston knows its spec sheet may not survive contact with the market.

The port also plans to bring Washington into the decision. "Maritime infrastructure like STS cranes touches multiple policy priority areas for the United States Government, which creates a unique opportunity for the right manufacturer," the RFP states. "We will be engaging in discussions with the federal government about this procurement and the best path forward that supports both Port Houston's technical, operational, and financial needs and the U.S. Government's focus on supporting the American maritime industry."

Who can actually build them?

ZPMC could deliver 10 cranes within two years without difficulty. Other OEMs face a tougher timeline — and the port shows no sign of flexibility there. "TIME IS OF THE ESSENCE for Seller's performance of the Contract," the RFP states with emphasis, adding that sellers must "proceed expeditiously with adequate forces" and hit manufacturing milestones.

Liebherr is an obvious candidate. The company holds 19 STS cranes on its order book for US ports over 2026-2028, per WorldCargo News' July 2026 STS market survey, and says capacity is not a constraint. "We have significant capacity to manufacture STS cranes each year" through its own production plus a "wide network of production facilities (who have experience with maritime cranes) within the Liebherr Group," the company said. "This gives us the flexibility to meet customer demand without capacity being a limiting factor."

One snag: Liebherr does not offer STS cranes with ABB drives and controls — a specification Houston may have to reconsider. Mitsui E&S, which had 23 STS cranes on order for 2027 delivery in the same survey, declined to comment on its annual capacity.

For US ports watching from the sidelines, Houston's tender is a test case: whether Western OEMs can fill the gap ZPMC may leave, at a price ports can pay, on a clock ports can meet. The answer will shape STS procurement strategy across the American coast well beyond this single order.