You don't get it, the 80% potential outputs of the new coal fire plants are conceptually energy storage (not in a conventional sense). When the renewables are putting out full power, the coal fire plants scale back their output. When the renewables aren't generating the power needed, the coal fire plants will take over.
You are the one that doesn't get it. That's fine if there's around a 50:50 ratio of renewables to coal, which is the situation today, you can scale up coal when renewables are low, and scale down coal when renewables are high . What happens when the ratio is more like 90:10 in 10 years? What happens when you can generate 5 terawatts of renewables at peak capacity and only have 500 gigawatts of coal at peak capacity to balance the books? No amount of scaling up or down of coal is going to balance the scales when the disparity is that high. And it's not like all of China's coal fleet can throttle up and down, only the the newer plants. Are you gonna spend trillions to build thousands of new coal plants to always have them at a 50:50 ratio with renewables?
Keep in mind that gigawatt scale power plants are not cheap. And a coal plant idling at 20% capacity or entirely idle for most of the year is losing money, you can't build too many of them. Gas peaker plants already exist, and their electricity prices are insane, because they have to make back their initial capital cost while only running a handful of times a year.
Also keep in mind that coal plants running on an unpredictable schedule is not the same as a battery or gas peaker plant running at an unpredictable schedule. Coal plants needs physical inputs of thousands of tons of coal on standby. Batteries don't need any physical fuel and gas peaker plants can use pipelines to quickly get access to their fuel. The logistics for moving thousands of tons coal are a lot more complicated if you don't know if you're gonna be idling for months at a time and suddenly might have to go 100% for days randomly.
Heat is a low-quality form of energy. There's like waste heat from all sorts of places.
Heat is great energy as it's easy to manage and many industries need raw heat anyway. All fossil fuel power is literally just heat engines, it's called thermal power for a reason.
Theoretically, once you have a completely electric vehicle fleet, you only need about 20% of that existing paid-for battery capacity for an entire day's electricity usage.
Vehicle to grid tech is still new and it depends largely on the consumer. Not a good idea for baseload storage.
