Last year during the winter I ran enough rigs to keep my house warm on all but the coldest nights without using the furnace. In fact, on many days unless it got below 0 degrees outside I had to have one or more windows open to keep it cool enough inside to be bearable. Even though electricity is more expensive than gas is my area for heat, with the dual purposing of mining and using the heat to warm the house it offset the electrical cost somewhat.
This year I am only running a few rigs mainly as hobby and they act as nice space heaters, but I still need to use the furnace routinely for heat and no open windows this year.
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