ABSTRACT
This chapter is solely devoted to wind and solar power due to their gaining importance in the energy mix of renewable sources. More than 94 GW of wind power generation has been added worldwide by the end of 2007, out of which over 12 GW is in the USA and 22GW in Germany alone. Looking at energy penetration levels (ratio of wind power delivered by total energy delivered), Denmark leads by reaching a level of 30% or more which is followed by Spain. In some hours of the year in Denmark, the wind energy penetration exceeds 100%, with excess sold to Germany and Nord Pool. Nineteen off-shore projects operate in Europe producing 900 MW. The US offshore wind energy resources are abundant.
