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We do not, in fact, need to build storage now. What we need now is renewable generating capacity to displace fossil fuel burning. At a time in the (not very di

We do not, in fact, need to build storage now. What we need now is renewable generating capacity to displace fossil fuel burning. At a time in the (not very distant) future, when we have enough of that above immediate needs to spare enough to charge storage, then we will start to need storage. 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.

robomartin 4y ago
> 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 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 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 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.
- moloch-hai 4y ago
  None of what you have posted is surprising. None of it changes the equation dictating build schedule. None of it favors nukes in any role. There is no need for "ten times" overbuild. Instead, you just need a backup generator you can fuel at need. Any tropical country can put up a solar farm and start exporting synthetic fuel. Until those are built, we can burn NG in shortfalls, at radically reduced average total carbon output. Building storage after you have enough renewable overbuild to charge it from, in normal conditions, incrementally reduces duty cycle on the generator. So, for a utility, a 1.5x overbuild and a few hours' 1x storage means they hardly ever run it. A transmission line to a neighboring utility cuts the fuel bill more, and makes selling excess easier. At home, with a grid tie-in, you need the generator only when a tree takes out the lines, and you can sell excess most days. A low duty-cycle backup generator should be, above other considerations, cheap. Don't you have one? They are cheap. In the future, 10x overbuild will be much cheaper than today, and would reduce your residual backup fuel bill if you care enough, and you can sell more power, most days. The correct course for a public utility is to focus on exceeding 1x average renewable generating capacity, and then add a bit of very dispatchable and quickly built storage--batteries. After that, incrementally overbuild, and add cheapest usable storage--not batteries--still using the combined-cycle gas turbine at need. The more overbuild and storage they add, the better things get. Maybe add some fuel synthesis equipment and tankage, and sell excess beyond local tankage. For home, keep your generator and/or grid tie-in ready. At 13 kW nameplate, you can usefully add some battery to carry you past peak evening price and, with a bit more, through most nights. Your neighbors with 4 kW are substantially reducing their power bill. There was no expectation of anything else.
  - robomartin 4y ago
    I have to ask: Do you have a solar array? I ask because of comments you have made such as: "you can sell excess most days"
    - moloch-hai 4y ago
      Yes. I have excess in summer. You can sell excess when you have excess. Some places (sadly, not all places), adding battery lets you sell excess at a higher price during peak times and maybe buy back off-peak.

robomartin 4y ago

> 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 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 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 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.

moloch-hai 4y ago
None of what you have posted is surprising. None of it changes the equation dictating build schedule. None of it favors nukes in any role. There is no need for "ten times" overbuild. Instead, you just need a backup generator you can fuel at need. Any tropical country can put up a solar farm and start exporting synthetic fuel. Until those are built, we can burn NG in shortfalls, at radically reduced average total carbon output. Building storage after you have enough renewable overbuild to charge it from, in normal conditions, incrementally reduces duty cycle on the generator. So, for a utility, a 1.5x overbuild and a few hours' 1x storage means they hardly ever run it. A transmission line to a neighboring utility cuts the fuel bill more, and makes selling excess easier. At home, with a grid tie-in, you need the generator only when a tree takes out the lines, and you can sell excess most days. A low duty-cycle backup generator should be, above other considerations, cheap. Don't you have one? They are cheap. In the future, 10x overbuild will be much cheaper than today, and would reduce your residual backup fuel bill if you care enough, and you can sell more power, most days. The correct course for a public utility is to focus on exceeding 1x average renewable generating capacity, and then add a bit of very dispatchable and quickly built storage--batteries. After that, incrementally overbuild, and add cheapest usable storage--not batteries--still using the combined-cycle gas turbine at need. The more overbuild and storage they add, the better things get. Maybe add some fuel synthesis equipment and tankage, and sell excess beyond local tankage. For home, keep your generator and/or grid tie-in ready. At 13 kW nameplate, you can usefully add some battery to carry you past peak evening price and, with a bit more, through most nights. Your neighbors with 4 kW are substantially reducing their power bill. There was no expectation of anything else.
- robomartin 4y ago
  I have to ask: Do you have a solar array? I ask because of comments you have made such as: "you can sell excess most days"
  - moloch-hai 4y ago
    Yes. I have excess in summer. You can sell excess when you have excess. Some places (sadly, not all places), adding battery lets you sell excess at a higher price during peak times and maybe buy back off-peak.