Comment by alvah
1 year ago
An impressive technical feat, but obviously there's no way a battery (i.e. storage technology) can actually replace a coal plant (i.e. generation technology) without additional generation. Sounds pedantic, but there are many headlines phrased this way, and many technically dumb people reading these headlines.
The article goes into this:
"The old coal generator provided three key values to Oahu, Keefe explained: energy (the bulk volume of electricity), capacity (the instantaneous delivery of power on command), and grid services (stabilizing functions for the grid, wonky but vital to keeping the lights on). The battery directly replaces the latter two: It matches the coal plant’s maximum power output (or “nameplate capacity,” in industry parlance), and it is programmed to deliver the necessary grid services that keep the grid operating in the right parameters."
Energy without batteries must be produced when it's consumed. Imagine your cellphone without a battery: it would be connected to a power plant that must be started on demand, and stopped when your phone is not in use.
Now imagine your phone gets a battery, that can be charged with a small solar panel when you're not using the phone. This way, you can use the phone even when the sun isn't shinning or at dark hours, as long as the solar panel and the sunny hours at least match you consumption.
The additional generation you call for comes from the windy/sunny times when people are not consuming 100% of production, so they charge the batteries instead.
In fact, coal can be thought as a storage of energy, not a source: it was stored from sun energy some million years ago when nobody was consuming it, so we can recover some of that energy today by pluging "the coal batteries" in a furnace.
I’m aware the battery in Hawaii uses additional generation, it’s mentioned in the article. That point was the obviously-misleading headline, which is not the first I’ve seen for this type of installation.
But my point is that you don't need additional generation. At night, a lot of wind energy is currently being lost, because 1) it doesn't get consumed and there's no means to store it and 2) the more eolic you install without batteries, the less ROI you get. Thus, you have to install extra-capacity for the day in the form of gas or coal. Now imagine you install batteries to store night wind energy: the show changes! You can actually replace a coal plant with a battery that can store enough wind energy at night that offset the coal plant, without extra generation installed.
This currently isn't true, because grids are not dumb. They are not over installing eolic or PV if they can't store the over production. But if batteries are price competitive, they might go that route. An eolic turbine that was previously stopped 50% of the nights, could be producing 24/7.
With the prevalence of cell phones and laptops in our life, accusing somebody of not understanding how a battery works is tantamount to an insult like calling them a man idiot. Who does not have to deal with charging their batteries continuously?
Further, it seems a bit hypocritical to complain about others reacting only to the headline without reading the article, when that's exactly what you have done.
Your assumptions are incorrect, and it’s perfectly valid to point out that a battery is not, in fact, a generator, when there are many headlines such as this one confusing the issue. There are many man idiots, whatever that means, making assumptions.
This headline does not confuse the issue.
The article is clear on how.
1 reply →