Bitdeer Technologies Group unveiled its Sealminer A4 series on April 7, 2026, with the flagship A4 Ultra Hydro achieving 9.45 J/TH efficiency, among the best figures in the bitcoin mining industry. The rigs are powered by Bitdeer's in-house SEAL04 chips and mark a direct challenge to established players like Bitmain and MicroBT.
Three Models for Hydro and Air Cooling
The A4 series includes: A4 Ultra Hydro (liquid-cooled) delivering 886 TH/s at 8,372.7W with 9.45 J/TH; A4 Pro Hydro at 680 TH/s, 7,412W, 10.9 J/TH; and A4 Pro Air (air-cooled) at 336 TH/s, 3,662.4W, also 10.9 J/TH. Power efficiency tolerance is ±5%, while hashrate and power tolerance are ±10%. Compared to the previous Sealminer A3 series (12.5–14 J/TH), the improvement is substantial. The A2 Pro ran at 14.9 J/TH. Each generation edges closer to the sub-10 J/TH target at the machine level.
Lower efficiency directly cuts electricity costs per bitcoin mined. Miners are under pressure after the April 2024 halving reduced block rewards from 6.25 BTC to 3.125 BTC, squeezing margins for operators with older, less efficient hardware. The hydro models suit high-density data centers with noise and heat constraints; the air unit serves sites without liquid cooling infrastructure.
Vertical Integration and Market Reaction
Based in Singapore, Bitdeer manages chip design, machine production, and data centers across the U.S., Norway, Bhutan, and Ethiopia. The A4 series will be used both for external sales and Bitdeer’s own self-mining fleet. On launch day, BTDR shares dipped about 1%, inconsistent with prior hardware launch events. Bitdeer disclosed no pricing, pre-order details, or shipping timelines.
The company previously outlined a chip-level roadmap targeting ~5 J/TH. The A4 brings sub-10 J/TH chip performance into commercially delivered hardware. Vertical integration gives Bitdeer cost control across the supply chain but concentrates R&D risk internally. No production volume targets or delivery schedules were announced.