Wind Energy for Cathodic Protection (Case Study #2)
All around the world, corrodible metals are exposed to air and rain. Replacing these structures would be a terrible expense for government and industry. Cathodic protection is needed to prevent corrosion of these vulnerable metals. This is done using a small negative voltage applied to metal. Bridges, wells and railway lines (to name just a few examples) can be protected against corrosion when a positive terminal is attached to the metal and a sacrificial anode is attached to a piece of scrap metal buried in the ground.
Small wind energy systems are used to power many cathodic protection systems. Wind turbine systems along with battery backup and other components work independently of the grid and are designed to go without source energy (wind) for up to a week.
This reliability and economics (much cheaper than running hydro lines to a remote area) make these renewable energy sources a big player in the cathodic protection industry (a $2 billion a year industry in the US).
Trestles, pipelines, steel tanks and marine locations are some other structures that benefit from cathodic protection provided by wind energy systems.