Liquefied Air Could Power Cars and Store Energy from Sun and Wind

[OKIsItJustMe]

17. The real question is not how much energy it takes to chill it

Because, then, you have to ask, “how much energy do you get back?”

So, your real question is “what is the overall efficiency of the system?” As “tinrobot” pointed out, the article says, “Highview Power’s process is 50 to 60 percent efficient…”

Of course, that was taken out of context:

…

Highview Power’s process is 50 to 60 percent efficient—the liquid air can yield just over half as much electricity as it takes to make it. Batteries, by contrast, can be more than 90 percent efficient. But the new process can make up for its inefficiency by using waste heat from other processes (see “Audi to Make Fuel Using Solar Power”). Highview has demonstrated that low-temperature waste heat from power plants or even data centers can be used to help warm up the liquefied air. The system can also last for decades, while batteries typically need to be replaced every few years. This longevity could help reduce overall costs.

…

Here’s the key point (once again from the article):

…

“When we’re looking at energy storage mechanisms, we’re looking for something that’s based on extremely low-cost materials and very simple processes we can do in bulk,” says Haresh Kamath, program manager for energy storage at the Electric Power Research Institute. “And this certainly fits the bill.”

…

And now, I have taken 6 paragraphs from the original article, rather than the recommended limit of 4.