If home mining isn't completely dead yet, it will soon be time to pull the plug and let it slide into darkness.
Casual home miners have 2 advantages over mining farms:
1. They might not care about electricity cost
Some of the miners run their rig as heating devices, some of them are living in a apartment that electricity is included in the rent. Once the electricity cost is gone, they are forever profitable
2. They can run in underwater
Even the electricity cost is higher than the coins, miners just regard this as a hobby and using those costs to get some mining pleasure, like paying money to play a game: Operating your little gold mine is fun
On the contrary, large mining farms are business oriented, if they could not sell the mined coins at profit, they will take a loss. No business can run too long with a negative profit, the larger the scale the less likely they can hold on
As a result, those mining farms will be shutdown by a sustained high difficulty and low bitcoin price, and mining rigs will be sold to those fans who does not care about the electricity cost
To prevent such scenario from happening, large mining farms might seek ways to lower the electricity cost, team up with large power supplier or build their own power grid. Another way is to sell the heat as a service, for example providing warm water for apartments. so that they never run underwater. But both are long processes, without a firm believe in bitcoin, normal farms will just shutdown
Because of the exponentially higher cost of lower chip nm process, high efficiency miners will be very expensive thus incur a larger risk even before running, just like few people purchased FPGA miners in GPU era
Maybe in future, majority of the mining chips will be built into heating devices, and sold into high latitude area or heat providing companies
