80 Plus (PSU Efficiency Rating)

80 Plus is a voluntary certification program (administered by CLEAResult) that rates how efficiently a power supply unit converts wall AC into the DC its load consumes. To earn the base badge, a PSU must hit at least 80% efficiency at 20%, 50%, and 100% of rated load. Higher tiers — Bronze, Silver, Gold, Platinum, Titanium — demand progressively tighter efficiency at each load point, with Titanium also adding a test at 10% load. For anyone running a PSU around the clock, the badge is a fast way to reason about how much of your electricity actually reaches the load and how much becomes heat inside the supply.

What the tiers mean in practice

Rough efficiency targets at 50% load run from about 85% for Bronze, through roughly 90% for Gold and 92% for Platinum, up to around 94% for Titanium. The lost percentage doesn't vanish — it becomes waste heat inside the supply itself, which the PSU's own fan then has to move. A 3,500-watt mining supply running at 93% efficiency instead of 85% sheds hundreds of watts less heat and draws meaningfully less from the wall for the exact same hashrate. Over a year of 24/7 operation, that delta is real money and real cooling load avoided. Efficiency also varies across the load curve: most supplies peak near 50% load and fall off at both extremes, which is one argument for sizing a PSU with headroom rather than running it pinned at 100%.

Mining PSUs: Titanium-class numbers, usually no badge

Here is the wrinkle miners should understand: the purpose-built supplies that ship with ASICs are usually not 80 Plus certified at all, yet many of them post efficiency numbers that would qualify for the top tiers. Bitmain's APW12, the workhorse behind the S19 family, runs roughly 93–95% efficient across its normal operating range — Titanium-class territory — without ever going through the certification program. Certification costs money and targets the consumer ATX market; ASIC vendors simply skip it. So the absence of a badge on a mining PSU tells you nothing negative. What matters is the manufacturer's measured efficiency curve, the input voltage it was specified at (mining supplies are typically rated at 200–240V, where efficiency is naturally higher than at 110–120V), and its power factor, which modern mining supplies hold near 0.99.

Why efficiency compounds for miners

Mining is uniquely unforgiving here because the load runs flat-out around the clock — there is no idle time for a mediocre efficiency curve to hide in. Even a few efficiency points compound across a fleet into thousands of kilowatt-hours per year. Supply efficiency also stacks with everything downstream: the hashboards' DC-DC conversion, the chips' joules per terahash, and your cooling overhead all multiply together into your true cost per hash. Higher-tier units tend to use better components and tighter voltage regulation as well, which matters for the stable rails ASIC hashboards prefer. On the repair bench we see the other side of the coin: supplies run hot and hard at poor efficiency age faster, and a failing PSU is one of the most common reasons a working miner goes dark. That said, an 80 Plus badge certifies efficiency, not raw capacity or build quality — always size the PSU's wattage to the miner with headroom, and treat the badge (or the datasheet curve) as one input among several.

Efficiency is only half the story; the other half is delivering that power cleanly to the racks. See the power distribution unit entry, and to understand how efficiency interacts with your bill, read about the time-of-use rate.