Zcash's 4x Mining Yield Is a Hardware Supply Artifact, Not an Algorithm Advantage

On September 11 a mining-economics note crossed my desk with two numbers that cannot both be true. Grayscale Research reports that Zcash miners earn roughly twice the daily revenue per machine as Bitcoin miners, and roughly four times the revenue per megawatt-hour. The same note places Zcash aggregate daily block rewards near $2 million. I ran the block schedule. Zcash targets one block every 75 seconds. That is 1,152 blocks per day. After the November 2024 halving, the subsidy is 3.125 ZEC per block. That is 3,600 ZEC issued daily. At the quoted $1,177, the chain pays out roughly $4.2 million per day. The gap is not rounding. It is a data-vintage problem, and it changes the entire comparison. The context matters because this is no longer a fringe privacy-asset story. Zcash has run since 2016 on Equihash, a proof-of-work algorithm deliberately chosen to resist the SHA-256 ASIC supply chain that industrialised Bitcoin. The two networks do not share hardware. Hashrate cannot vote with its feet, so each chain carries its own security budget in isolation. On August 25, Grayscale's Zcash Trust converted into a spot ETF under the ticker ZCSH. Two weeks later it had absorbed more than $500 million. ZEC broke $1,000 for the first time in nearly a decade, printing around $1,177, while year-to-date network hashrate expanded by more than 2.5 times. Zcash market capitalisation sits at roughly 1% of Bitcoin's. Those are the real inputs. Now the arithmetic, because the arithmetic is the whole story. The $2 million line fails two independent cross-checks. If $2 million were current issuance at today's price, ZEC would have to trade near $550, which is precisely where it sat before the September 4 breakout above $1,000. Alternatively, if the figure is net of the developer fund, which claims roughly 20% of block rewards, the miner-attributable payout is about $3.4 million, still well above $2 million. Both explanations point to a stale snapshot blended with a fresh price. That matters because every downstream ratio inherits the error. A $500 million ETF inflow over 14 days is about $35.7 million per day. Divided by stated issuance, that is an 18x coverage ratio. Divided by reconstructed issuance, it is closer to 8.5x. Still dominant. Half as dramatic. The hardware side, by contrast, reconciles cleanly. If revenue per machine is 2x and revenue per megawatt-hour is 4x, then the implied power draw of a Zcash machine is half that of a comparable Bitcoin unit. Equihash rigs typically sit in the 1 to 3 kW band; current-generation SHA-256 machines run 3 to 5 kW and above. Two ratios, one consistent hardware assumption. The Grayscale dataset at least agrees with itself on the physical layer. So does the Bitcoin leg. Post-halving issuance is roughly 450 BTC per day. A stated $35 million daily reward pool implies a Bitcoin price near $78,000, before fees. Plausible. And the market-cap cross-check holds: $1,177 multiplied by roughly 16.3 million circulating coins lands near $190 billion, about 1% of Bitcoin. Price data is internally consistent. The reward line is the outlier. The data does not lie, only the narrative does. Which brings the real mechanism into focus. The 2x and 4x figures are not a verdict on Equihash, on privacy, or on zk-SNARKs. They are a verdict on ASIC scarcity. Equihash application-specific capacity is small, concentrated among a handful of fabricators, and delivered on long lead times. When a price re-rates faster than fabs can ship, the incumbent miner captures a temporary rent. That rent is the entire outperformance. It is not a protocol feature. It is a supply-chain bottleneck wearing a technical costume. Yields are temporary; the ledger remains eternal. Grayscale describes the setup as a self-reinforcing dynamic: high miner revenue attracts hashrate, hashrate hardens the network, the network supports the price. The first half is true. The second half inverts. Hashrate growth is not a moat, it is a margin tax. Annualised 2.5x hashrate expansion compounds near 8% monthly. Price has been moving closer to 15% weekly. Difficulty is currently lagging price, which means miners are being paid on yesterday's competition. That lag always closes. When it does, per-machine economics compress from both directions: more hash competing for the same reward pool. I watched this shape before. In 2020, during DeFi Summer, I built a Python scraper across more than a hundred liquidity pools, tracking APY, TVL, and unlock schedules daily. Sixty percent of advertised high yield was inflationary emission with no external revenue behind it. The farms that looked strongest in week three looked emptiest in week nine. Zcash is not a farm, and it is not a Ponzi. The block subsidy is transparent and the cap is fixed at 21 million. But the loop has the same geometry: price up, capacity in, yield down. Reflexivity cuts one direction at a time. There is a second blind spot, and it is structural. Equihash retains GPU-mineable properties. Zcash's absolute hashrate remains orders of magnitude below the SHA-256 pool, and rented hash markets let an adversary purchase attack capacity rather than build it. The note does not price that risk. Nor does it examine the protocol work that actually matters to holders, Halo 2 and Orchard, which removed the trusted setup from the shielded pool. This is a mining-economics document. Its silence on cryptography is not an oversight; it is a scope boundary. Silence between the blocks reveals the true intent. One governance detail deserves a line. Roughly 20% of block rewards flow to developer entities. That allocation is recurring, transparent, and historically contested. It is not a hidden unlock, but it is permanent sell pressure with discretion attached, and it sits on the same ledger as everything else. Two lines to watch next. First, Equihash ASIC delivery cadence: the month shipments catch up is the month the 4x collapses. Second, ZCSH daily net flow: ETF capital is now the marginal buyer, and at roughly 8.5x daily issuance it sets price while miners only take profit. If net flow stalls while hashrate keeps compounding, the same ledger that produced this rally will produce the compression. Due diligence is the only alpha that compounds.