> We do not, in fact, need to build storage now.

No, we do. Well, perhaps saying storage isn't quite accurate. What we need is reliable power, because solar is not.

Perhaps you have not seen the charts I posted from my 13 kW array showing what we produced in the last three months compared to the same period last year?

Here:

https://imgur.com/bo0s7b0

This was caused by rain and weather. The very direct implication of this is that solar power requires an external reliable power source. Without it you could have entire cities go dark.

And so, the question is: If solar cannot work without an additional power source capable of delivering 100% of the required power for prolonged periods of time, why are we insisting on building two power systems, one solar and one using a different technology?

> There is no point in even talking about building nukes. Nukes are dead, dead, dead. Not because of regulation, or hippies, but because no one with the money would waste it building one.

Forget I said nuclear then. Solar at scale cannot happen without having a reliable power source available to support it. If we want to stick with clean sources, the only real options are wind and hydro. Nuclear, I would highlight, is cleaner than burning stuff to make energy. Yet, again, let's not discuss nuclear for the moment.

Because of the characteristics of solar you have to two at least two things:

- You have to grossly over-build by ten times or more

- You have to have a backup power source that can
deliver 100% of the required peak power for minutes,
hours, days and even weeks.

The grossly overbuild part is very easy math to understand. Let's take the simplest of them all: No sun at night. This means --in very rough strokes-- that if you want to store the equivalent amount of energy for night-time use, you have to double the system. One half of the array supports daytime use while the other half charges 100% efficient storage (not a reality) for use at night.

That's not the end though. In a practical reality (feeding a neighborhood, town, city) you need constant power. In a perfect day (no clouds, rain, etc.) the output of a solar array looks like an inverted parabola. Here's a chart from my system.

https://i.imgur.com/aNnbmDp.png

In order to deliver the same amount of energy as a constant-power system of the same peak power output, you need to build a solar array 1.5 larger than this. That's because the integral of the area under the inverted parabola is 2/3 the area of the enclosing rectangle. Simple math.

Now we are to having to build a system of 2 x 1.5 = 3 times larger.

The you have bad days, like this one:

https://i.imgur.com/breTHQd.png

This happens more often than most people might imagine. The cause, in this case, clouds. Not ugly dark clouds, beautiful white clouds during an beautiful blue-sky day. When it comes to solar, clouds are evil.

I won't continue with the math. I'll just say that, when you consider all the issues with solar (including seasonal output, negative power coefficient and dirt) you can easily see that if you want 1 GW of output you better consider building a 10 GW array, or more. And this requires massive amounts of storage, otherwise you have no power at night or during some of the issues I presented above. As the other charts show, the last few months taught me a lot about what can happen.

Going back to having to build a 100% reliable power system that can supply 100% of the power needs to support unreliable solar. At some point you have to ask yourself. If you are going to build a full duplicate power system, just to have solar, does it really make sense?

This is where reality smacks you in the face again. Sure, there are places in the world where one could use hydro and wind. That isn't going to solve the problem though. You can't use these technologies everywhere. Wind also has its problems.

This is why I tend to reach for nuclear. I can't think of any other technology that can provide 100% power availability at nearly 100% of the time. The other requirement is that we have to be able to start building it now, not in ten years (see above). In the US, it could take well over 25 years to build any type of reliable-power generation plant. We just don't have the ability to move quickly any more. Which means that there's a practical limit function to how far we could take solar, because it isn't reliable and it requires 100% backup.

Not a simple topic. I obviously believer in solar enough to have spent my own money and built a nice 13 kW system. I will be expanding it to 20 kW this year. I might consider going to 30 kW next year. Why? I can't charge enough batteries for the system to deliver power reliable enough to support electric vehicles. This is another reality. Most of my neighbors have small 3 to 5 kW systems. They are all screwed. I talk to them all the time. Some regret having solar because it is costing them more per month (due to leasing and the rising cost of power) than when they put these inadequate systems in. Some were told they could charge electric cars with solar, which was 100% false.

I love solar. I believe in it. I simply prefer to talk about it in real terms and not in a fantasy world where the technology is perfect, reliable and has no issues.