However, doubt has been cast on the much-vaunted advantages of renewables due to some of their characteristics, such as availability, security and affordability.
—
If you are going to put it that way…
You should contact the authors of the paper; I’m sure they have plenty of references.
Diogo Santos Pereira - University of Beira, Covilhã, Portugal
António Cardoso Marques - NECE-UBI, Covilhã, Portugal
José Alberto Fuinhas - University of Coimbra, Coimbra, Portugal
DB2