Survey of Energy Resources 2007
Geothermal Country Notes
The limited geothermal resources in mainland Portugal have been developed for direct use, whereas geothermal occurrences in the Azores are utilised for the production of electricity as well as being used directly.
Twelve areas with potential for developing geothermal electricity generation have been identified on the islands of Faial, Pico, Graciosa, Terceira and São Miguel in the Azores. Two plants are in operation on São Miguel: Pico Vermelho, a 3 MWe back-pressure steam turbine integrated in a single-flash system and Ribeira Grande with 2 x 2.5 MWe + 2 x 4 MWe ORMAT dual turbo-generators. The 3 MWe unit at Pico Vermelho is due to be replaced, with a new units with a capacity of up to 10 MWe.
Research has shown that the island of Terceira has a high-temperature resource suitable for power generation. Construction of a 12 MWe plant is planned for 2009. Output will then meet approximately 50% of local electricity demand.
Low-enthalpy occurrences are spread throughout the mainland and have been harnessed for small district heating schemes, greenhouse heating and bathing and swimming (including balneology). Direct use in the Azores excludes district heating. To date there has been little interest in geothermal heat pumps. At end-2004, total installed capacity stood at 30.35 MWt of which 27.09 MWt was for bathing and swimming, 1.79 MWt for greenhouse heating and 1.47 MWt for district heating.