A 1-megawatt solar project could provide power over the 25-year life of the project at about 5 cents per kilowatt-hour or less (substantially less than the approximate 10 cents per kilowatt-hour of industrial grid power in California).
More in depth info here: https://www.greentechmedia.com/articles/read/solar-powered-bitcoin-mining-could-be-a-very-profitable-business-model#gs.3bjvd=g
A typical mining rig with a single ATI HD 5970 with the minimum components (PSU, mobo, HD, graphics card) will consume about 380W. At the difficulty level on April 9, 2011 (82347) using a modern miner that hash about 600MHash/S with that hardware, the cost of electricity to generate a block is $6.84 USD, using the typical U.S. residential rate (about $0.11/kWh).
Given that a block is 50 BTC and the BTC/USD market rate on that date was about $0.75 USD, then over 18% of the proceeds from mining went to pay the cost of electricity required to mine that block.
with reference to https://en.bitcoin.it/wiki/Power_Calc
But if we were to use Solar Power only, then the mining will need to setup preferably at the desert where initial cost to setup the solar power farm.. Otherwise , estimated Solar system power cost is about 10x the price of buying from the grid.
A 1-megawatt solar project could provide power over the 25-year life of the project at about 5 cents per kilowatt-hour or less (substantially less than the approximate 10 cents per kilowatt-hour of industrial grid power in California).
In answer to your question, I found the average electricity rates by state for bitcoin mining. I also found an article that discuss how it is profitable to mine for bitcoin if you can save money on electricity. Hope these help.
This development model can also be pursued in areas that have no power lines and very cheap land. No grid connection is required to do the mining. Under this scenario, the miners are connected to the internet via a satellite connection, but otherwise the entire project is off-grid. All solar power is used for mining. This kind of facility could also include onsite storage to both smooth production and to extend mining operations beyond daylight hours.
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