Besides supplying a plentiful, renewable, affordable supply of electricity, one of geothermal's biggest benefits is its minimal effect on the environment.
While geothermal does pose far fewer environmental challenges than most other energy or industrial operations, toxic gasses and minerals are occasionally encountered as operators go deeper in search of more productive and sustainable reservoirs. These elements require mitigation. Current recovery methods have proven to be extremely effective, as have scrubbing techniques that protect the air from emissions such as hydrogen sulfide gas.
Low CO2 emissions
Carbon dioxide is a natural byproduct of geothermal steam, but it is less than 4% of what is typically released by coal and other fossil fuel plants. In a closed-loop geothermal system, there are no CO2 emissions.
Fewer on-site chemicals, less environmental exposure
Once wells start producing, naturally occurring scale in wells can be removed by acidizing techniques. To minimize acid handling at the wellsite, Halliburton's acid components arrive in a dry form and then are mixed on site (Acid-on-the-Fly) in a special acid blender. This greatly minimizes environmental exposure to pre-mixed chemicals along the transport route from the supplier's facility to the destination, and helps ensure that only the precise amount of acid needed will be mixed, thereby eliminating disposal issues.
A smaller footprint than conventional energy extraction operations
Thanks to minimal equipment, a relatively small area of land is needed for injection and production wells. Add to that the fact that geothermal generating stations are located right on the site—which means these stations don't have to take up space somewhere else—and it's easy to see why geothermal has less impact above and below the surface than other energy operations.