Singapore-based mining hardware and infrastructure provider Bitdeer Technologies introduced its next-generation Bitcoin miner, the Sealminer A4 series, on April 7, 2026. The flagship liquid-cooled model, A4 Ultra Hydro, sets a new industry benchmark with an efficiency rating of 9.45 J/TH, making it one of the most power-efficient Bitcoin miners publicly announced to date. This represents roughly a 24% improvement over the previous A3 series (12.5 J/TH).
Three Models for Diverse Deployments
The A4 series comprises three variants. The flagship A4 Ultra Hydro delivers 886 TH/s with 8,372.7W power consumption. The A4 Pro Hydro offers 680 TH/s at 7,412W (10.9 J/TH), and the air-cooled A4 Pro Air provides 336 TH/s at 3,662.4W (10.9 J/TH). All models are equipped with Bitdeer's proprietary SEAL04 chips, fabricated on advanced process nodes. Efficiency ratings carry a ±5% tolerance, while hashrate and power figures have a ±10% tolerance.
The liquid-cooled variants are designed for high-density data center environments where thermal management is critical, while the air-cooled version offers flexibility for sites lacking liquid cooling infrastructure. Bitdeer emphasizes that the water-cooled models deliver low-noise operation and improved thermal stability, which supports higher uptime in large-scale operations.
Iterative Improvement in a Post-Halving Era
The A4 series marks a significant leap from earlier generations. Bitdeer's A3 series (released September 2025) had an efficiency of 12.5-14 J/TH, while the A2 Pro operated at 14.9 J/TH. With each generation, Bitdeer moves closer to its long-stated goal of sub-10 J/TH performance. The improvement is particularly timely: after the April 2024 Bitcoin halving slashed block rewards from 6.25 BTC to 3.125 BTC, miners have faced relentless pressure on hashprice and margins. Lower J/TH ratings directly translate to reduced electricity costs per Bitcoin mined, a critical factor for remaining profitable with older, less efficient hardware.
Bitdeer operates as a vertically integrated supplier, managing chip design, hardware manufacturing, and data center operations across the United States, Norway, Bhutan, and Ethiopia. The A4 miners are expected to support both external sales and Bitdeer's own self-mining fleet, which the company has been expanding through successive Sealminer deployments.
Market Reaction and Roadmap
On the day of the announcement, Bitdeer's Nasdaq-listed shares (BTDR) declined approximately 1%, a different response compared to past hardware launch events. Bitdeer did not disclose pricing, pre-order details, or a shipping timeline for the A4 series. As of press time, the company's official product page had not been updated with A4 specifications.
The A4 launch extends Bitdeer's chip development roadmap, which targets roughly 5 J/TH at the chip level in future generations. The company previously demonstrated sub-10 J/TH results in chip-level benchmarks under optimized conditions; the A4 series brings this performance to commercial hardware. By controlling the entire supply chain, Bitdeer aims to compete directly with established manufacturers like Bitmain and MicroBT, although it now carries the full R&D risk internally.