The beginning of mythology, the foreshadowing of its collapse.

In just two months, Zcash ($ZEC) has become the most dazzling focus of the entire crypto market. It has surged from $50 at the end of September to a recent high of $730, an increase of 1460%, and its FDV has soared to an 8-year high of $13 billion.

 https://www.coingecko.com/en/coins/zcash

What further fueled the excitement was the endorsement from a host of top figures: the endorsements from heavyweights like @naval, @0xMert_, and @CryptoHayes acted as a catalyst, igniting market FOMO and attracting numerous KOLs, retail investors, and even some funds to re-examine this established blockchain. Unusually, both Chinese and English versions of CryptoKitties (CT) were enthusiastically discussing ZEC, the privacy narrative, and the resurgence of ZK technology, with Privacy seemingly once again being hailed as the protagonist of the "next big trend" in the crypto market.

However, beneath this seemingly glamorous and perfect narrative, some key fundamental issues have been consistently overlooked: Are ZEC's miner economic model, network security, and on-chain interaction activity truly sufficient to support an FDV of over 10 billion US dollars?

ZEC is on the eve of a typical Hardware-Price Scissors scenario in the history of PoW.

Before discussing the sustainability of any PoW project, the economic incentives at the mining end often most directly reflect the chain's ability to capture value.

Let's calculate ZEC's current payback period together:

1) Z15 Pro: Currently the most mainstream mining rig

The most discussed and sought-after new flagship ZEC mining rig on the market right now is the Bitmain Antminer Z15 Pro, whose hardware specifications are as follows:

Hashrate: 840 KH/s
Power consumption: 2780 W, actual operating power consumption is around 2560 W.
Energy efficiency ratio: 0.302 kWh/W

Currently, the official website only offers Z15 Pro pre-orders, with delivery in April 2026, priced at $4,999. Those who can't wait can also try to buy a used one on the black market, such as Xianyu, where the real price is around 50,000 RMB.

https://m.bitmain.com/zh/product/detail?pid=00020251112140439260bFAoSY2F0667

2) ZEC's computing power and mining revenue structure: astonishing daily earnings

Over the past two months, ZEC's high returns have been rapidly attracting computing power, leading to a significant increase in the network hashrate and a rise in difficulty. The chart clearly shows that ZEC's price (yellow line) broke out of its sideways trend at the end of September, while the hashrate (light purple) and difficulty (dark blue) rose in tandem. This trend indicates that mining has begun to react to the price increase.

 https://minerstat.com/coin/ZEC

As of writing, the key parameters of the Zcash network are:

Total network computing power: 13.31 GH/s
Network difficulty: 118.68M
Block reward: 2.5 ZEC/block

To calculate daily earnings, we input the Z15 Pro's parameters into the mining earnings calculator and set them up as a standard miner:

Mining pool fee: 2%
Electricity price: $0.08 / kWh
Daily electricity consumption: $5.34 ($2.78 kW × 24 hours × $0.08/kWh)

Then we can arrive at an amazing figure: a single Z15 Pro generates a net profit of over $50 per day! And historical data shows that this high profit has been sustained for at least a week.

https://whattomine.com/coins/166-zec-equihash

3) Payback period: Extremely high ROI

Assuming that the network difficulty remains unchanged in the short term and electricity costs are stable, we use the Z15 Pro mining rig futures price of $4,999 to calculate the payback period.

To reflect the true cost, the mining machine is amortized on a straight-line basis over 5 years (1826 days):

Daily machine cost amortization: $2.74
Daily net income after amortization: approximately $47.63

Therefore, the static payback period for a Z15 Pro is only about 105 days, which translates to an annualized return of nearly 350%.

This number is extremely rare—even unusual—in the entire history of PoW:

The payback period for BTC mining rigs during a price surge typically takes 12–24 months.
The ROI of mining machines in the ETH PoW era is between 300 and 600 days.
Historically, PoW projects with a payback period of less than 120 days (such as FIL, XCH, and RVN) almost all collapsed after several months.
The latest BTC mining rigs currently generate approximately $23 in daily profit, with a static payback period of about 3.4 years.

4) Case Review: The Recurring Issue of Hardware-Price Scissors

Hardware-Price Scissors is a recurring "harvesting" scenario in the history of PoW mining. Miners order mining machines at several times the premium when the price of the coin is at its highest and FOMO sentiment is at its strongest (at this time, the ROI seems extremely low, with a payback period of only 4 months). However, when the mining machines are actually delivered and the hashrate skyrockets (usually with a delay of more than 3 months), the big players often sell off their holdings at high prices, causing miners to face a double whammy of "coin price halving + production halving," and their mining machines instantly become overpriced scrap metal.

In May 2021, Chia triggered a global hard drive shortage. At that time, the price of XCH surged to $1,600, and the static payback period for early hard drive investments was compressed to less than 130 days. This extreme profit instantly triggered a global surge in storage computing power. However, what followed was a drastic "scissors difference": despite the drop in the price of the coin, the hard drives ordered earlier continued to come online, and the total network computing power continued to surge after the price of the coin peaked, rapidly extending the payback period from 30 days to more than 3,000 days.

Observing the data of the IceRiver KS1 miner, its payback period once dropped as low as 150 days in mid-2023. Unlike Chia, the price of KAS even maintained an upward trend. However, even so, miners still lost money because the slope of hashrate growth far exceeded the slope of coin price increase. The rapid iteration and large-scale deployment of industrial-grade ASICs caused the network difficulty to rise exponentially. Despite the stable coin price, due to the surge in difficulty, the payback period of the KS1 machine still irreversibly soared to 3,500 days.

ZEC's computing power is currently in a dangerous range, having been subjected to 51% attacks multiple times in its history.

Beyond the mining economic model, another decisive risk factor is the network's security and computing power scale. For PoW chains, "total network computing power scale + 51% attack cost" directly determines whether they can be self-consistent under a high valuation.

1) Total network hashrate: Equivalent to only a small to medium-sized Bitcoin mining farm

According to the latest network data, ZEC's total network hashrate is approximately 12.48 GSol/s. Based on the hashrate of 0.00084 GSol/s for a single Z15 Pro miner, only about 14,857 Z15 Pro miners are needed, corresponding to an energy consumption of approximately 40 MW, which is equivalent to the scale of a small to medium-sized Bitcoin mining farm.

From the perspective of the overall network's computing power, Zcash's security foundation appears extremely weak, and it has entered the risk zone of many small PoW chains that have been successfully attacked by 51%.

 https://miningpoolstats.stream/zcash

2) Attack cost: Theoretically only in the millions of dollars range.

Generally speaking, launching a 51% attack requires controlling more than 50% of the network's computing power at the same time. If the ZEC network's nearly 16,000 Z15 Pro devices constitute the main force, then an attacker could potentially control more than 50% of the computing power simply by renting or purchasing a few thousand devices.

Rough estimate:

The cost of each Z15 Pro pre-order unit is approximately $5,000. Orders of 300 units or more typically constitute large customer purchases and are eligible for at least a 10% discount.
Controlling computing power: ~8,000 units → Cost: at most ~$40M, Energy consumption for the attack: around 20 MW
If leasing or resale prices are lower, the actual start-up cost could be in the millions of dollars.

On a public blockchain with an FDV of nearly $10 billion, the potential chain reorganization or double-spending can be initiated with only a million-level computing power investment, which is a structural risk that cannot be ignored.

3) Compared with mainstream blockchains: a huge gap in security.

To give everyone a more intuitive and clear understanding, let's make a simple comparison with other running large-scale PoW chains:

More importantly, ZEC's current hashrate is not only far lower than that of mainstream PoW chains such as BTC/LTC/KAS, but even chains such as ETC, BTG, VTC, and BSV, which have been successfully attacked by 51%, generally had higher hashrates than ZEC when they were attacked. This means that ZEC's network security has actually fallen into a dangerous range where it can be attacked.

On-chain data reveals that ZCash's actual usage remains very limited.

Despite the recent surge in ZEC narratives, on-chain data offers a more sober perspective—there is a significant discrepancy between actual usage and the current FDV of tens of billions.

From transaction volume and active addresses to ecosystem size, Zcash's actual network behavior is far less vibrant than its price movements suggest.

The average daily transactions over the past month were only 15,000 – 18,000, which is only 1% – 2% of that of large public chains.
As a privacy blockchain, the vast majority of transactions remain transparent, with shielded transactions accounting for less than 10%.

 https://zechub.wiki/dashboard

Repricing when the market returns to calm after a period of frenzy

Narrative, emotion, celebrity influence, and the economic trap of mining machines have collectively propelled an eight-year-old project to the forefront of public opinion. However, beneath the surface of excitement, when we truly return to the three core aspects of blockchain—economic sustainability, cybersecurity, and on-chain adoption—ZEC presents a completely different picture.

This is:

A crackdown on mining scams with a payback period of only 105 days and an annualized return of 350%.
With a computing power equivalent to only a medium-sized Bitcoin mining farm, a 51% attack cost as low as a million dollars, transaction volume only 1%–2% of mainstream public chains, and privacy features actually used in less than 10% of PoW chains, this is a PoW chain.

History has proven countless times that extremely short payback periods (extremely high ROI) are often a harbinger of mining disasters and cryptocurrency price crashes.

I cannot say for sure whether ZEC will be an exception.

But the rules of the crypto world have never changed: narratives and emotions can create myths, but fundamentals determine how far a myth can go.

End.

*Special thanks to @0x010crypto and @0xTZ_DeFi for their contributions.

The U.S. Indo-Pacific Commander stated during a Senate hearing that Bitcoin has the potential to be a "computer science tool".

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