Creating earthquakes....please elaborate on this idea. How is using the heat that is in the crust of the earth CREATING earthquakes?
The cost is a relative idea. I don't know the installation cost of a full scale steam turbine system, but when they are installed they will have constant power. I would guess that the biggest cost down the road would be the preventative maintenance on the turbine generators, but if designed and build properly, that will be minimal at worst. The installations cost would be FAR smaller than then coal burner, or nuclear power plants, which take constant fuel supply and huge amounts of land respectively.
I guess another negative effect would be the loss of jobs for the people that were drilling for oil and mining for coal to supply power, but they could be employed to create the geothermal plants...so that is probably a wash.
Whoever owns the power being generated from the plants will have a huge windfall in profits, so if that is NOT you, then that could be a negative effect.
As for the local small geothermal systems for homes or buildings, even with the added cost of installation the systems pay for themselves within a few years being very conservative. I would recommend these on any and all new builds.
I'd like to hear some of your other ideas as to what else might be negative.