Iren hands Microsoft its first 50MW at Childress, and a schedule to be judged by

Iren said Horizon 1, the first building at its Childress, Texas campus, has been delivered to and accepted by Microsoft ^[1]. It is the first of four 50MW IT-load, direct-to-chip liquid-cooled buildings scheduled for delivery to Microsoft at that site this year ^[2], which means the five-year, $9.7bn cloud services contract the two companies signed in November 2025 ^[3] now has capacity behind it rather than only a signature.

The word doing the work in the announcement is "accepted". A developer can declare a building finished on its own authority; acceptance is the customer's judgement. Iren has cleared that bar once, on the first of four units of identical stated size, and in doing so has published the terms on which the rest of its year will be read: 50MW handed over, 150MW to go ^[1][2]. Co-founder and co-CEO Daniel Roberts said the company looks forward to delivering Horizons 2 to 4 later this year, and credited more than 3,000 people across the site team ^[4]. Three buildings in the months remaining is a schedule anyone can check without a briefing, which is a different position from the one Iren occupied in November.

The Childress numbers put the milestone in proportion. Four buildings at 50MW each is 200MW of IT load ^[1], roughly 27 percent of the 750MW the campus is set to offer at full build-out across 576 acres, on land that previously hosted cryptomining gear ^[5][3]. Spread evenly, the Microsoft contract averages about $1.94bn a year over five years ^[4], though Iren has not said how that revenue is phased against building acceptances.

The delivery also matters to the company's balance-sheet story. Iren, formerly Iris Energy, is still mining Bitcoin but is winding those operations down and diverting the cash flow into its AI cloud business ^[6]. Its fleet stands at about 23,000 GPUs, and in October it said contracts had been secured for around 11,000 of them, leaving roughly 12,000 without disclosed contracts at that point ^[7][5]. Against that, the stated ambition is 480MW of gross AI cloud capacity in 2026 and 1.2GW gross in 2027, a two-and-a-half-fold step in a single year ^[8][6]. Note the unit mismatch: the Childress buildings are specified in IT load while the 2026 and 2027 targets are stated as gross capacity, and no conversion is supplied, so the two sets of figures are not directly comparable ^[7].

Execution is spread thin geographically. Founded in 2019, Iren has sites live or in development in Texas at Childress and Sweetwater, in Oklahoma at Kiowa, and in British Columbia at Mackenzie, Prince George and Canal Flats, plus a targeted project in South Australia and the recent acquisition of Spanish developer Nostrum ^[9].

What to watch: the interval between Horizon 1 and Horizon 2 acceptance, because the first gap sets the credible cadence for the remaining two; whether all three land inside the calendar year or slip into next; whether contracted GPUs move closer to fleet size ^[7]; and whether the 480MW gross target for 2026 is ever restated in IT load, which is the only figure comparable to what Microsoft has now accepted ^[2][8].