Aena Sticks with E‑Auctions in €13bn Airport Build Programme, Defying Contractor Demands

Aena’s Tender Push and the Builders’ Pushback

Spanish airport operator Aena has started tendering the first contracts of its €13bn investment programme for the 2027‑2031 regulatory period (DORA III), and it is sticking firmly to an electronic auction system that forces bidders to compete on price – despite vehement opposition from construction lobbies. The industry associations Seopan, Anci and the CNC have asked Aena to abandon the auction mechanism, arguing that fixed‑price bids are increasingly unworkable in an environment of volatile material and energy costs. They also want all contracts to include a formal price‑revision clause. So far, Aena has largely resisted.

The first four large projects published tell the story. Only one – the €464m comprehensive remodelling of Tenerife South terminal – carries a price‑revision mechanism, and even that is limited: it kicks in only after three years and 20% of the work is done, and it applies only to a basket of materials such as aluminium, copper, cement, steel and energy. Contracts for the expansion of Madrid‑Barajas T4 North (€89.9m), the T4S south pier (€56.5m), a car park overhaul at Tenerife (€48.5m) and runway resurfacing at Almería (€29.2m) all lack any cost‑indexation, despite large direct‑cost components.

The construction sector is now openly warning that some firms may simply refuse to bid for projects without a rebalancing mechanism if inflation continues to bite. The Confederation of Construction (CNC) has already counted 1,877 public‑works contracts elsewhere in Spain that received only one bid or none at all in the first half of the year, largely because of soaring material costs. Aena’s own recent experience adds weight to the fear: the €223m Palma airport terminal contract in 2022 attracted just two offers, with Acciona beating Sacyr by a tight margin.

Aena officials argue that the e‑auction is triggered only after a strict technical pre‑qualification, so the final award is not solely price‑driven. They also describe the inclusion of price‑revision in the Tenerife terminal contract as “a significant change compared with what was done until now”. Nevertheless, with the DORA III plan due for final approval at the end of September, the stand‑off over risk allocation is casting a shadow over the largest airport infrastructure programme in Spain’s recent history.

Why the €13bn DORA III Programme Is Turning into a Risk‑Allocation Fight

The Auction Model: Aena Transfers Risk, Contractors Push Back

Aena’s electronic auction is designed to squeeze out every last euro of savings. Once at least three bidders pass the technical threshold, they are invited to submit progressively lower offers, with a minimum reduction step of €2.8m in the Tenerife terminal case. The baseline for “reckless” bidding is set at 30% below a correction band tied to the arithmetic mean of the bids. The system gives Aena maximum price certainty but leaves successful bidders exposed to raw‑material, energy and labour inflation that a fixed‑price contract cannot absorb. The construction associations’ request for collaborative “alliance” contracts – common in Anglo‑Saxon public works, where client and contractor share risk and decision‑making – has been flatly rejected, reinforcing the impression that Aena is unwilling to change course.

Why Tenerife Got Price‑Revision and the Others Didn’t

On paper, the presence of a price‑revision clause in the Tenerife South terminal contract is a breakthrough for builders. Aena’s own tender documents justify it by the project’s “high budget, complexity and 96‑month execution period” – factors that “determine the need to incorporate mechanisms to manage the proper economic adaptation of its delivery, avoiding imbalances that threaten viability.” Yet the clause is far from a blanket guarantee: it excludes the first three years and the initial 20% of work, meaning the contractor must absorb all cost volatility during what is often the most intense construction phase. For other contracts with shorter deadlines – 35 months in Barajas T4 North, 24 months on the T4S pier, 19 months in Almería – Aena has simply concluded that the duration does not justify a revision mechanism, even when direct costs represent 80% or more of the budget.

The Bidder Turnout Threat and the Palma Precedent

The CNC’s warning about deserted tenders is not theoretical. The Palma airport contract in 2022, awarded at the height of the post‑Ukraine inflation shock, drew only two bids. The winning offer from Acciona came in 11.4% below the base budget – a significant cut at a time when input costs were soaring. If similar caution re‑emerges across the DORA III pipeline, Aena could face delays that feed directly into its regulated capacity targets. The €2.4bn Barajas expansion alone is supposed to lift the airport’s ceiling from 70 million to 90 million passengers; any slip in procurement would ripple through the entire timeline. Builders with heavy bitumen exposure, for example, are looking at the Almería runway contract – where a price‑revision clause would be most relevant given spiking bitumen costs – and already weighing whether it is worth the risk.

Winners and Losers in the Current Set‑Up

Aena stands to gain if competitive tension forces down contract prices, boosting the return on its regulated asset base. For the larger construction groups, the programme is a once‑in‑a‑decade opportunity but also a margin trap: those with deep balance sheets may accept the risk to secure market share, while mid‑tier firms could be forced to stay on the sidelines. The ultimate loser would be the travelling public if capacity expansion falls behind schedule because too few contractors are willing to work on terms they consider unsustainable. Equally, a contractor that wins a low‑ball bid but then faces a cost blow‑out may end up in financial distress, jeopardising project continuity – a scenario that would harm both Aena’s reputation and its execution credibility.

What Contractors and Aena Should Watch Next

For construction companies:

• Model each DORA III project individually against your own cost base – the 30% low‑bid threshold and absence of price revision on contracts under 36 months mean exposure is heavily concentrated in the first two years of work.
• For the Tenerife terminal contract, note that price‑revision is activated only from year four and excludes the first 20% of execution; the listed basket (aluminium, copper, cement, steel, bitumen, energy, etc.) covers relevant materials but not labour or finance costs.
• Weigh the Almería runway resurfacing contract carefully – despite a high bitumen component, no cost‑indexation is provided and the 19‑month deadline leaves zero room for input‑price spikes.

For Aena and its stakeholders:

• Track the number of bids per tender from the very first project; a repeat of the Palma two‑bid scenario should immediately trigger a review of auction parameters or price‑revision inclusion.
• Monitor the end‑September DORA III approval event – any political or regulatory push for more balanced risk‑sharing could force a mid‑course adjustment.