Geothermal handbook: PlanninG and Financing power Generation t e c h n I c a L r e p o r t 2 / 2

 
CON | 
The ability of geothermal power plants to follow the demand for electricity is limited, and
attempting to do so can increase power generation costs.
6 | PrO | 
Under favorable geological conditions, power generation from geothermal resources is
amongst the least cost options for power generation and can in many instances compete with
ADVANTAGE
DOWNSIDE/CHALLENGE
Globally inexhaustible (renewable)
Resource depletion can happen at individual 
reservoir level
Low/negligible emission of CO
2
and local air 
pollutants
Hydrogen sulfide (H
2
S) and even CO
2
content is 
high in some reservoirs
Low requirement for land
Land or right-of-way issues may arise for access 
roads and transmission lines
No exposure to fuel price volatility or need to 
import fuel
Geothermal “fuel” is non-tradable and location-
constrained
Stable base-load energy (no intermittency)
Limited ability of geothermal plant to follow 
load/respond to demand
Relatively low cost per kWh
High resource risk, high investment cost, and 
long project development cycle
Proven/mature technology
Geothermal steam fields require sophisticated 
maintenance 
Scalable to utility size without taking up much 
land/space
Extensive drillings are required for a large 
geothermal plant
10
Geothermal plants are extremely reliable and typically operate more than 95% of the time, with some plants at over 99%. This compares 
to availabilities of 60%-70% for coal and nuclear plants (Kutscher 2000). In this handbook, the availability factor of geothermal installations is 
generally assumed to be 90%.

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G e o t h e r m a l H a n d b o o k : P l a n n i n g a n d F i n a n c i n g P o w e r G e n e r a t i o n 
nuclear, coal, and gas on levelized generation costs.