What will happen to mining post ETH Merge currently planned for Q1 2022
Short answer: no one knows
Alchemys opinion:
Disclaimer- Everything below is estimations for illustration purposes
Ethereum nethash snapshot 689.56 TH/s for Sep 05 2021 (7.77 USD per 100MH/s)
Ravencoin nethash snapshot 7.62 TH/s for Sep 05 2021 (14.30 USD per 100MH/s)
Ergo nethash snapshot 30.42 TH/s for Sep 05 2021 (2.9110 USD per 100MH/s)
Lets use top tier cards for examples:
3080: ETH 100MH/s, RVN, 46 MH/s/s, Ergo 190 MH/s/s
6800: ETH 63MH/s, RVN, 29 MH/s/s, Ergo 115 MH/s/s
3070ti: ETH 40MH/s, RVN, 32 MH/s/s, Ergo 151 MH/s/s
Now we assume 30-40% of Ethereum is asics so lets remove that from the equation. 689.56 TH/s x 0.60 = 413.736 TH/s
For simplicity lets take that number and say its all 3080s. 413.736 TH/s = 413736000 MH/s / 100 MH/s = 4,137,360 RTX 3080s worth.
Now lets take that amount of 3080s and add it to the other networks.
RVN takes them all:
4,137,360 x 46 MH/s = 190,318,560 = 190.318TH/s
7.62 TH/s + 190.318TH/s = 197.938TH/s an increase of 2497.61%
RVN profits per 100MH/s
14.30 x 0.04%= 0.572 = 57.2c USD per 100MH/s
3080: RVN, 46MH/s/s = 26.3c USD per card (279w @ 10c per KWH- 67c per card) total = (negative)-40.7c USD per card
6800: RVN, 29MH/s/s = 16.58c USD per card (203w @ 10c per KWH- 49c per card) total = (negative)-32.42c USD per card
3070ti: RVN, 32MH/s/s = 18.3c USD per card (216w @ 10c per KWH-52c per card) total = (negative)-33.7c USD per card
Ergo takes them all:
4,137,360 x 190 MH/s = 786,098,400 = 786.098TH/s
30.42TH/s + 786.098TH/s = 816.518TH/s an increase of 2484.15%
Ergo profits per 100MH/s
2.9110 x 0.04%= 0.116 = 11.6c USD per 100MH/s
3080: Ergo, 190MH/s/s = 22c USD per card (220w @ 10c per KWH- 53c per card) total =(negative) -31c USD per card
6800: Ergo, 115MH/s/s = 13.34c USD per card (134w @ 10c per KWH- 32c per card) total =(negative)-18.66c USD per card
3070ti: Ergo, 151MH/s/s = 17.5c USD per card (204w @ 10c per KWH-49c per card) total = (negative)-31.5c USD per card
Likely Scenario RVN and Ergo Split the hash:
RVN
4,137,360/2 x 46 = 95,159,280 = 95.159 TH/s
7.62 TH/s + 95.159TH/s = 102.779TH/s an increase of 1148.806%
RVN profits per 100MH/s
14.30 x 0.074%= 1.0582 = 1.058 USD per 100MH/s
3080: RVN, 46MH/s/s = 48.7.3c USD per card (279w @ 10c per KWH- 67c per card) total = (negative)-18.3c USD per card
6800: RVN, 29MH/s/s = 30.6c USD per card (203w @ 10c per KWH- 49c per card) total = (negative)-18.4c USD per card
3070ti: RVN, 32MH/s/s = 33.8c USD per card (216w @ 10c per KWH-52c per card) total = (negative)-18.2c USD per card
Ergo
4,137,360/2 x 190 MH/s = 393,049,200 = 393.049TH/s
30.42TH/s + 393.059TH/s = 423.479TH/s an increase of 1292.107%
Ergo profits per 100MH/s
2.9110 x 0.077%= 0.116 = 22.4c USD per 100MH/s
3080: Ergo, 190MH/s/s = 42.56c USD per card (220w @ 10c per KWH- 53c per card) total = (negative)-10.44c USD per card
6800: Ergo, 115MH/s/s = 25.76c USD per card (134w @ 10c per KWH- 32c per card) total = (negative)-6.24c USD per card
3070ti: Ergo, 151MH/s/s = 26.425c USD per card (204w @ 10c per KWH-49c per card) total = (negative)-22.575c USD per card
I realize this does not take into account the other GPU coins, but their emissions are minimal.
Again this is for illustration purposes do not get caught up in the math, this is only to help prevent FOMO.
TLDR : Without a major market shift, mining profitability for many will be low, cents per card, lowest power costs will survive.