The Front Cover
Bill Leighty argues in his article on page 6 that rather than just extending electricity grids it would be worth looking at alternatives (such as hydrogen and ammonia carried via underground pipelines) for storage and transmission of renewable energy. The image of the frontcover shows a solution-mined compressed Hydrogen storage caverns in domal salt.
American wind energy rebounded in 2014 but will this continue?
Alternatives to Electricity for Transmission, Storage and Integration of Renewable Energy
By Bill Leighty, The Leighty Foundation, Juneau, Alaska, USA
The Hexcrete Wind Turbine Towers
By Sri Sritharan, Wilson Engineering Professor, Department of Civil, Construction and Environmental Engineering, Iowa State University, USA
Measuring Low-Frequency Vibrations
By Dr Edwin Becker, Pruftechnik Condition Monitoring GmbH, Germany
View from Inside
Global Wind Hits Record Growth
Steve Sawyer, GWEC Secretary General, Belgium
Projects and Contracts