Wednesday, November 18, 2015

Deep foundations not essential to withstand earthquake

Coquimbo was hit by the tsunami but wind turbines were not damaged (pic: Sfs90)

by Tom Azzopardi:

CHILE: Some 600MW of wind projects installed in Chile are in the northern region that bore the brunt of the massive earthquake and tsunami on 16 September. Nonetheless, all survived the tremor without a scratch, and most were reconnected to the grid in minutes.

Only damage to auxiliary equipment, such as substations and transmission lines, interrupted supplies to local homes.
"It took us just 50 minutes to return to services because of a problem with the transformer," said Javier Varas, operations manager at the 114MW Los Coruros wind farm, in Coquimbo.

Of the 900MW of wind projects installed since 2008, around two thirds are located along the wind-swept, sparsely populated coast of the northern region of Coquimbo.

The resilience of these projects is not surprising, said Horacio Musante, a partner at geotechnical consultants Geofun. The demands put on wind farms by seismic movements are generally less than those imposed by the wind itself.

Rather than spending too little on foundations, Musante said Chile's wind developers could actually be spending too much — critical when foundations can represent a significant proportion of the final cost of a project.

When the first farms were installed in Chile a decade ago, developers insisted on deep-pile foundations similar to those used in the sandy clays of northern Europe. But most Chilean projects are located on high-lying areas with good quality soils and do not need deep foundations.

Due to inexperience in Chile, many projects combine remote locations with deep foundations, making them an expensive proposition.

"You have to adapt to the local conditions and the local technology," says Musante.

Shallow wind turbine foundation received their first test in Chile with the Lebu-Toro wind farm in the southern region of Biobio. In February 2010 an earthquake struck, killing more than 500 people and causing an estimated $30 billion worth of damage, yet the seven turbines barely moved.
You may also like:

No comments :

Post a Comment