Answer to Question 1
Geothermal energy occurs where the hot molten rock of Earth's interior is close enough to the surface to heat groundwater. Two ways in which geothermal is being used are electrical production and space heating.
Answer to Question 2
Ecosystems can in fact be restored. The amount of work required to restore an ecosystem depends on the extent of disruption to the ecosystem. In the simplest case restoration simply involves stopping the abuse from human use or overuse. In other cases, extensive time and money must be invested into the ecosystem to return it to normal. Despite great efforts, however, some restoration efforts are unsuccessful. Success will include the following three factors: (1) abiotic factors must have remained unaltered or, if not, can at least be returned to their original state, (2) viable populations of the species formerly inhabiting the ecosystem must still exist, and (3) the ecosystem must not have been upset by the introduction of one or more foreign species that cannot be eliminated and that may preclude the survival of reintroduced native species.
Energy costs of locomotion.
Ammonium as an energy source for chemoautotrophic bacteria in soil.
Bonding Partners and Energy May Change in a Chemical Reaction
Free Energy
Iceland Geothermal Resources
Energy flow and chemical cycling