2. Geothermal energy
Geothermal energy is the heat that comes
from the sub-surface of the earth. It is
contained in the rocks and fluids beneath the
earth's crust and can be found as far down to
the earth's hot molten rock, magma. There
are three types of geothermal power plants;
dry steam, flash and binary. Geothermal
energy is used in over 20 countries, but I will
focus on Poland and Tenerife.
3. Geothermal energy in Poland
Poland is a country where geothermal energy
has been used on a limited scale for space-
heating for a dozen years. Although lacking
in spectacular geothermal manifestations, the
country has a considerable low-enthalpy
potential, placing it among the most
prospective countries in Europe.
4. Geothermal energy, similar to other renewables, develops in
the shadow of the traditional power industry, the coal industry
in particular. More favourable legal regulations, as well as
economic and fiscal incentives, should be introduced. They
would be a tool for the promotion of geothermal energy and,
first of all, the creation of equal opportunities for geothermal
and traditional fuels – a starting point for the rational energy
policy.
In Poland there are six geothermal energy plants:
- The Podhale region (since 1992)
- Pyrzyce (since 1996)
- Mszczonow (since 1999)
- Uniejow (since 2001)
- Slomniki (since 2002)
- Stargard (since 2005)
I will present three of them:
5. The Podhale region
The plant in the Podhale region (the Carpathians) was the first geothermal space-heating facility in
the country. Its experimental stage was designed, constructed, and launched in 1987-1993. Since
1994, a large geothermal heating project has been under realisation. By autumn 2001, the
network supplied geothermal heat to over 220 buildings. In late 2001, a considerable part of
receivers in Zakopane – the main city of the region (population 30,000, over 4 million tourists/year)
were connected to the heating network.
6. Pyrzyce Geothermal Power Plant
The space-heating plant in Pyrzyce (the Polish Lowland Province)
was designed and built between 1991-1996. It has been owned and
operated by the limited-liability company "Geotermia Pyrzyce”
established by the National Fund for Environmental Protection and
Water Management, Pyrzyce County, the Voivodeship Fund for
Environmental Protection and Water Management in Szczecin, and
the State Treasury. The geothermal aquifer is situated within the
Jurassic sandstones at depths of 1.4 to 1.6 km. The total thickness of
reservoir formation is about 150 m, while the reservoir temperature
is 64 C. Static water level is present 34 m below ground level. Water
is drawn with the use of submersible pumps.
8. Uniejów Geothermal Power Plant
Uniejów (the Polish Lowland Province) is a small town (3,200 of population) situated in Central Poland. Thanks
to natural conditions and landscape, the town and its vicinity are very attractive for the development of
countryside tourism, especially for nearby agglomerations of Warsaw and Lodz – two of the largest ones in the
country. An integrated geothermal-oil space-heating plant was put into operation in 2001.This geothermal
aquifer is situated within the Cretaceous sandstones at depths of 1900-2070 m. It belongs to the same
regional formation which is being exploited in Mszczonów. The reservoir temperature is about 70°C. The
maximum flowrate is 90 m3/h of 68C water in terms of self-outflow (4 atm static). The TDS are relatively low,
at the level of 8 g/dm3.Water is exploited in one doublet of the well system
9. Geothermal energy in Tenerife
The Canary Islands are located off the Northwest African coast, these tiny
Spanish islands are undertaking a revolutionary feat of utilizing
renewable technologies to fulfill a large percentage of their energy
demands by the year 2030. Currently, the largest island - Tenerife is
already generating about 42% of its electricity from wind power.
10. Studies from the 1970s and 1980s realized within the National Energy Plan by the
Geological and Miner Institute of Spain, considered the
Canary Islands as having the highest potential for the development of geothermal
energy in Spain. Primary evidence of the geothermal
potential which exists comes from an underground hydrothermal system in the
subsoil of Tenerife with a temperature of 275°C. Since
then, it has become a necessary venture to evaluate whether it is possible to
exploit the resource utilizing the scientific and technological
developments reached in the past years.
11.
12. Currently, surface explorations are being conducted on the islands of
Tenerife, Gran Canaria, and La Palma. Within the past 500 years, there
have been 14 volcanic eruptions in the Canary Islands. The rich,
volcanic history of these islands has already made them predisposed to
the potential of being explored for geothermal resources. The project
Termovolcan aims to promote the development of geothermal energy
through the objectives of designing and developing innovative
geophysical and geochemical methodologies that will improve the
exploration of geothermal resources in Tenerife, Gran Canaria and La
Palma.
13. High enthalpy deposits of high temperature (above 100-150 ) mainly for power generation.
Low enthalpy geothermal energy or low temperature for heating and cooling, mainly in tourist
facilities and shopping centers.
Surface geochemical and geophysical surveys have already started in all three islands.
Geothermal energy in the Canary Islands
