Over the last decade hydroelectric plants achieved the production of around 30% of energy consumption needs in Portugal. The current hydroelectric network exploits 50% of the water potential in Portugal, around 5000 MW of power, by way of 66 large-scale dams and 150 mini water plants.
The new National Energy Strategy set as its priority the achievement of 8,625 MW of installed power by 2020 which may raise energy of water origin to 40%. This solution reduces by over 180 million Euros per year the import of fossil fuels and greenhouse gas emissions (CO2).
The National Dam Plan carries out the mission of driving the development of new hydroelectric projects and optimising existing water infrastructures to maximise their hydroelectric potential. This commitment will allow an increase of around 75% in installed hydroelectric power by 2020.
WATER
Water energy consists of the transformation of the mechanical energy of water under the effect of gravity into electrical energy resulting from the topographical unevenness originated by a weir or dam.Hydroelectric plants are made up of dam systems where water is stored on a temporary basis and by way of canals whereby water flows are channelled for the conversion of mechanical energy into electrical energy.
Hydroelectric equipment may be reversible and operate as a complement to wind production. Wind Energy may be used to re-pump water into the reservoir to be used in the production of water energy, where necessary.
In Portugal ten new projects of high hydroelectric potential and the improvement of six existing dams are foreseen.
The installed power at hydroelectric plants in 2009 stood at 4,972MW, with an annual potential of production of over 16TWh. The goal set for 2020 is to achieve 8,625 MW of installed power, hoping to achieve in this year 70% of usage of the national water potential.
Large-scale dams
Height of over 15m, storage capacity of over 1 million cubic metres of water.
| Dam |
|
HEIGHT |
CAPACITY |
ÁREA |
POWER |
ENERGY PRODUCED
/YEAR |
 |
ALTO LINDOSO
Higher
installed power |
|
110m |
379 Mm3 |
1525 Km² |
639 MW |
948 GW/h |
|
AGUIEIRA
Multiple purposes
and pumping |
|
89m |
423 Mm3 |
3100 Km² |
270 MW |
210 GW/h |
|
ALQUEVA
Largest artificial lake
in Europe |
|
96m |
4150 Mm3 |
55 000 Km² |
240 MW |
269 GW/h |
|
MINI WATER PLANT
The energy of river water may be taken advantage by way of a mini water plant installation which transforms the kinetic energy created by the natural or artificial topographical unevennesses into electricity.
The mini water plants have power of lower than 10 MW. In Portugal around 100 mini water plants are installed with a total capacity of 365 MW.
OCEANS
The energy of the oceans is used in various ways, each of which has a specific technology: waves, maritime currents, tides, gradients of temperature and salinity. The waves constitute the form of ocean energy used most in Portugal by way of equipment which capture the movement brought about by said waves.
Portugal has an extensive coastline, undulation of excellent characteristics with very high energy density and appropriate bathymetry. The resource is very stable and foreseeable with relative immunity to local climate effects and a minor time variation.
The potential for electrical energy production from wave energy on the Portuguese Atlantic coast was estimated assuming a resource of 30 kW per km of coast and that an average percentage of 15 percent of incident energy may be converted into electrical energy. Waves with large amplitudes (> 2 m) and long periods (7 to 10 s) have energies of over 40~50 kW/m. The potential for electrical energy production associated with said coast is estimated at 10 TWh per year at 50 m deep. For the same 250 km, using the value of 20 MW of installed power per kilometre, the installed power may stand at 5 GW.
Portugal has a world, prestigious leadership position in terms of technical and scientific knowledge about wave energy after over 20 years of research developed by the IST (Further Technical Institute) and INETI (National Institute of Engineering, Technology and Innovation).
Experimental projects:
- Porto Cachorro Wave Energy plant, Pico Island, the Azores, 1999 –, 400 kw, OWC technology –Oscillating Water Column
- Submerged pilot plant in Almagreira, Peniche, 2007 -, 2 MW, AWS technology – Wave Roller
- Wave Farm in Aguçadoura, Póvoa do Varzim, 2008, 2,25 MW, Pelamis technology