FAQ Geothermal


1.What are the benefits of geothermal energy?
First it is clean. Energy is produced without the need of fossil fuel. Geothermal fields produce only 1/6 of the carbon dioxide a relatively clean natural gas power plant produces. Geothermal energy is available 24 hrs/day 365 days/year.


2.Why is geothermal a renewable source?
Because the source of geothermal is the unlimited amount of heat generated by earth`s core. Even if geothermal dependency on reservoirs, the volume taken out can be injected back making it a renewable source.


3.What are the environmental impacts of geothermal technology?
Low emissions, salts and dissolved minerals are re injected to the reservoir with excess water. Recycling the geothermal water replenishes the reservoir. If solid materials require disposal they are being sold to the chemical industry.


4.Is it possible to deplete geothermal reservoirs?
Pressure and production declines have been experienced in some power plants, however reinjecting the water the pressure maintains to the desirable levels. In the City of Santa Rosa California wastewater is used as a reinjection fluid, prolonging the life of the reservoir while recycling treated wastewater.


5.What are the different types of geothermal?
There are three types of geothermal technology. The dry steam, flash steam and binary cycle. The selectivity of the geothermal type depends on the fluid state (steam or water) based on the available temperature.


6.What makes a site good for geothermal electric development?
Geothermal fluid temperature over 1000C (ideal temperature 150 0C), with low mineral or gas content, shallow aquifiers, easy access to transmission lines or load, availability of make-up water for evaporative cooling.


7.What is enhanced geothermal system (EGS)?
EGS is an artificial subsurface reservoir, where there is insufficient or little natural permeability or fluid saturation. The fluid is then injected into the subsurface under carefully, controlled conditions, creating permeability.


8.How efficient is GSHP?
Heating efficiencies of 50-70% and cooling efficiencies of 20-40%.