Case studies


 

Corvo


 
NAME: Corvo
Corvo
LOCATION: Azores, Portugal
GEOGRAPHIC COORDINATES:

39 40' N and 31 50' W

AREA: 17 km2
POPULATION: 430
TOPOGRAPHY:
Low hills, terraced plains and coastal cliffs.
CLIMATE:
Subtropical humid climate, rainy winters (> 13C) and hot summers (> 22 or 23C), no dry season during the warmest period.
GRID:

Isolated, 2x200 kW Diesel generator units

     
The supply of electricity to an isolated small island such as Corvo is very limited, while there is a great concern with environmental issues related to fossil fuel supply, such as water and land contamination and pollution by oil products and wastes through leakage during shipping handling and storage.

 

Table 1. Energy data for the island of Corvo

 

Year
Consumption (GWh)
Production (GWh)
2000
0.678
0.763
2001
0.723
0.809

 

In Corvo Island, the security of supply is a real and frequent concern, since due to bad weather conditions it is common to have oil shortages in this island. To reduce Corvo's dependency and secure supply, the implementation of an energy system that combines RES and storage is the best solution.

 

 

SCENARIOS

 

In order to show the pathway for Corvo renewable island, 3 scenarios of energy supply were set:

 

Wind 30% - baseline scenario, limiting intake of wind electricity to 30% on hourly basis, and thus not overloading wind turbine with supplying ancillary services.

 

Wind Reversible Hydro - wind and hydro scenario, with wind turbine being able to supply ancillary services, and thus allowing for 100% momentaneous penetration, storing the excess wind electricity by pumping.

 

Wind Reversible Max. Hydro - wind and maximised hydro scenario, similar to previous, but with running strategy-giving advantage to hydro, thus increasing the stability of the grid.

 

Corvo_ph

 

Figure 1. The hydro-pumping storage system proposed for Corvo Island

 

While in first scenario the penetration of renewable energy, wind reaches 25%, in wind-hydro scenarios it is possible to supply 70% energy from renewable sources, thus significantly increasing the security of supply.