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If 19% of the power for the country is being generated by wind, then there is clearly a large reduction in carbon footprint.
The article claims, ‘not a single power plant was shutdown’.

So how is that possible...

To understand how it is possible, you have to understand how the electrical system works. 19% of the kwH delivered may have been from wind, but the wind is not a steady reliable producer. For instance, in one part of the day, wind may be providing 30 or 40% of the total demand, but then the wind can slow or even stop entirely, and demand must be met from other sources.

Conventional steam plants, be they coal, gas, oil or biofuel, can not be switched on and off like a light switch. They have to be ready to generate extra MW at a moment's notice since the wind is so intermittent. To do so, they have to have a fire burning in the boiler, generating steam, and have the turbine spinning and synchronized to the grid running at low power or even no power -- a very inefficient way of operating. Only then can they ramp up to meet demand and keep the grid from crashing entirely. So while the wind is blowing, these conventional plants are still operating, burning fuel, but not operating at their highest efficiency levels, which is typically 100% power.

That is just the generation side of the equation. Wind also causes some unique problems on the transmission side. It is vital that the grid be balanced from a voltage and frequency standpoint, and because wind changes by the second, the output to the grid can cause voltage and frequency to vary beyond acceptable values and the higher the percentage of wind on the grid, the more dramatically values can jump. To keep the grid balanced, conventional plants that can respond rapidly must be deployed to track the frequency and voltage to keep the grid balanced.

The “19% of the power” is misleading as well. As you pointed out, power and energy aren’t the same thing. So while it may be that the wind turbines can produce 19% of the power it might only be for limited amounts of time. It would be nice to know what the percentage of kWH is being produced.

The other issue I have heard from utility people, is that it is hard to balance the KVARs from these turbines. They need fossil plants that utilities can directly control to deal with the reactive loads.

>>> To understand how it is possible, you have to understand how the electrical system works. <<<< I understand how the electrical system works. Okay. >>>> To do so, they have to have a fire burning in the boiler, generating steam, and have the turbine spinning and synchronized to the grid running at low power or even no power <<<< Try again. The wind is ONLY providing 19% of the power consumption. Assuming that the coal/gas power plants can provide supply all of the power needed at 80% capacity, this means that the power plants are cut back to a net of 61% capacity when the wind is a peak supply. A gas burner is typically designed for a 2/1 turndown ratio. So the (net) plants would be well within their 50% to 100% operating range. So no, overall they would not be at no/low power. If you do a bit of digging, what you will find they are actually complaining about is that the CO2 emissions credits are being sold to other places and those places are operating facilities to maintain the CO2 levels.