An curved arrow pointing right. A $1.5 billion energy-generating lagoon on Wales' south coast could be the first of many wave-harnessing power stations around the world. More from Tech A $1.5 ...

About 30 miles southwest of Reykjavik, the Blue Lagoon is Iceland's most popular tourist attraction. This geothermal spa welcomes more than 700,000 annual visitors. For a little perspective ...