The Renewable Energy Foundation is a registered charity promoting sustainable development for the benefit of the public by means of energy conservation and the use of renewable energy.

REF Publishes
New Collection of Papers on Wind Power Variabiity in Germany, Denmark, and Ireland
The Variability of Wind Power: Collected Papers 2009-2011 (x + 53pp) brings together five papers all concerned with the topic of wind power variability, and all grounded in rigorous examination of large bodies of empirical data. The contents comprise:

1. "Wind Power and Spot Prices in Denmark and Germany: Statistical Survey 2009"
2. "Wind Power Variability: Observations and Analysis"
3. "Wind Power Variations are Exported"
4. "Geographical Distribution and Wind Power Smoothing"
5. "The European Wind Integration Study Final Report"

Copies of the book are available free on request from
Renewable Energy Foundation, 21 John Adam Street, London, WC2N 6JG; 020 793 3636; press@ref.org.uk.

They have a good number of additional  pdf publications available HERE