> If there's a small amount of power available then it's not worth mining.

Could you explain how you arrived at this conclusion? The value of mining is generally proportional to the available power. If the capital expense of a mining rig is less than a transmission line, it might be better to mine than to transmit. For example, if it costs 1 million dollars to install a transmission line, but only 1 thousand dollars to setup a mining rig that could consume all the energy, it probably be more feasible to mine than to transmit.