Islands trying to use 100% green energy failed, went back to diesel

Islands trying to use 100% green energy failed, went back to diesel:
"The islands of Tasmania and El Hierro tried to power their economies with 100 percent green energy, but both islands eventually went back to diesel generators after suffering reliability problems and soaring energy costs.
These islands may be on opposite sides of the Earth, but they became poster children for environmentalists campaigning for countries to ditch fossil fuels.
The fact remains that Tasmania and El Hierro saw their energy sectors become costly failures after going green, according to the free market Institute for Energy Research (IER) published Thursday.
“One of the biggest reasons that natural gas, oil, and coal are the world’s most-used energy resources is because they are incredibly reliable,” Daniel Simmons, vice president for policy at IER, told The Daily Caller News Foundation.
“By the same token, wind struggles to compete with conventional fuels because it is inherently unreliable.”
...El Hierro was supposed to be the poster child for 100 percent green energy.
The island, located in the Spanish Canary Islands, replaced its diesel power plant with a hybrid wind power and pumped hydro storage system worth $94 million in 2014. 
The system has only been active since June of 2015.
The expensive system, however, provided an unpredictable amount of power and couldn’t even electrify the entire island.
...The sheer unpredictability of the system damages the island’s electrical grid and forces the island to rely on the diesel power it was supposed to replace..."