One of the big thorns in the side of today’s renewables is intermittency: the sun doesn’t shine at night, the wind blows when it wants to, and so on.
So you need back-up energy sources to fill in the holes between bursts of renewable energy. Typically that has meant coal or gas plants.
But all kind of crazy ideas are coming out to play these days involving energy storage that can be pumped into the system when the renewables are having a break. The most obvious storage option is batteries. But there are others on the horizon. From CNBC:
“Work has started on a liquid air energy storage site in the northwest of England, with the team behind the project stating it will be one of the largest energy storage systems in Europe.
“Highview Power’s 50 megawatt facility in Greater Manchester will harness technology that uses something called “air liquefaction.”
“The system involves a number of steps: excess or off peak electricity powers an air liquefier. This cleans, compresses then cools ambient air, turning it into a liquid at -196 degrees Celsius (around -320 Fahrenheit). According to the company, this liquid air is “stored at low pressure and later heated and expanded to drive a turbine and generate power.”
“The technology being deployed by Highview Power stems from an idea developed by Peter Dearman, the brains behind the concept of a “liquid air engine.” According to the U.K. government, Dearman — who’s been described by the BBC as a “self-taught backyard inventor” — worked alongside a team from the University of Leeds to develop the idea of “using air as a form of energy storage” when compressed and liquefied.”
I can just see the guy waking up one morning, lying in bed staring at the ceiling and it coming to him in a flash that you could store energy in liquid air. I mean, I don’t know about you, but I have ideas like that nearly every day.
Not.
There’s also been more and more talk recently about using pumped hydro storage, whereby you pump water up a mountain when the going’s good, and then let gravity take it back down through the turbines when the wind stops or the sun checks out for the evening. It turns out this is not even one of the new kids on the block:
“Cruachan Power Station, for instance, is a hydroelectric pumped storage facility housed in a hollowed-out Scottish mountain.
“The site was officially opened by Queen Elizabeth II in 1965, with its final two turbines coming online in 1966 and 1967. Back in August, the Drax Group announced it would benefit from a £1 million upgrade to improve its efficiency.
”According to Drax, the Cruachan station uses reversible turbines to take water from Loch Awe, a 41 kilometer long freshwater loch, or lake. In order “to store excess power from the grid,” the turbines pump this water to an upper reservoir on the side of the mountain.“The stored water is then released back through the turbines to generate power quickly and reliably when demand increases,” the business adds. The site can produce power in under a minute when required.”
The Queen was still a youngster when she opened that.
[Cover photo by Scott Webb on Unsplash]