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Renewable Energy Storage -- What's Real?

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I didn't know that. According to Emissions from the Cement Industry it is currently 50% of total emissions; I only addressed the other 50%. To which my answer is: "Just plant more trees!" If we terraform Earth with the equal numbers of trees to remove cement kiln chemical reaction CO2, then we should be OK, but I think there's a transport problem getting the CO2 to the trees. Maybe we can pipe it in to those new forests. Then, I'd look to removing the energy CO2 by using solar as I described.

The conveyer belts bringing in lime from the mines (all but 1 cement factory in the world get their lime from colocated mines (since it is (considered) uneconomical to do otherwise)) could run through tubes that carry the CO2 back the other way for a large part of the distance, reducing overall cost of transporting the CO2 to the man-made forests. Unfortunately, I don't think it could be mixed with the water misting systems to hydrate the terraformed forests, since that creates "Carbonic Acid". Nothing is free I suppose.

Some answers to that question:

Fast growing: CO2 (carbonic acid) uptake through roots? - GardenBanter.co.uk

http://www.treedictionary.com/DICT2003/shigo/RHIZO.html

The last link gets deep into chemistry. I haven't figured out if Carbonic Acid helps or not from that description, yet.
Annnnd ... scratch that idea for now, until someone hires a bunch of tree and forest biologists to study it. While reading it, I realized there is a lot of detail. Once the detail is figured out, it might or might not work.
 
@ecarfan & @Jeff N I'll happily concede I oversimplified my CO2 comment, but I'll remain a non-fan of Al Gore mainly because I'm leery of prophets making profits and I don't like hypocrisy (e.g., politicians cashing in for hundreds of millions, while flying around on private jets, while mandating how others should live). Hopefully you won't hold that against me while I try to practice what I preach by educating others how they can personally improve our planet through conservation (the best solution that's rarely mentioned), switching to LED bulbs, adding DG solar, driving a Model 3 (or S/X if one can afford the luxury), installing a Powerwall 2, etc. I do appreciate your input ;)
One, Al Gore isn't a politician, and hasn't been one since 2001. Two, he isn't mandating anything. Three by that standard of yours you should be hating on Elon Musk. Four Donald Trump has holding in fossil fuel companies which he has not placed in a blind trust, and has made decisions that directly affect those businesses. He's also trying to kill off environmental regulations which would help those businesses, and is trying to undermine green forms of electrical generation in the US.
 
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No it won't. You will be powering your neighbors on your low voltage distribution circuit. To the utility your exported power will appear as lower overall distribution load. Releasing stored off-peak energy during peak hours will actually help reduce congestion on distribution and transmission lines, and would help prevent utility-scale solar curtailment. Electricity flow does not work like data packets on the internet.
I'm thinking of a situation where output from batteries+PV is more than local demand on the low voltage distribution circuit and the extra is exported to the grid. It probably isn't possible, but my feeling is it could increase congestion since the homeowner is importing energy off peak to store in their battery pack and exporting it on peak instead of more solar being installed in whichever low voltage distribution circuit is still pulling a lot of energy from the grid on peak.
 
I'm thinking of a situation where output from batteries+PV is more than local demand on the low voltage distribution circuit and the extra is exported to the grid. It probably isn't possible, but my feeling is it could increase congestion since the homeowner is importing energy off peak to store in their battery pack and exporting it on peak instead of more solar being installed in whichever low voltage distribution circuit is still pulling a lot of energy from the grid on peak.

It probably isn't possible. More importantly any issues due to over supply during peak hours are far... far less likely than issues due to lack of supply... A smart grid would further reduce problems... it doesn't even need to be that smart. The grid has a built in health meter... frequency. 60hz... everything is ok. 60.3 too much power... please charge your batteries. 59.7... I need some juice... The limiting factor there is that it's the same everywhere since it's a synchronous grid... so it won't help with local congestion just overall supply/demand. You can actually see frequency dip in the evenings and rise in the mornings with a voltmeter...
 
I'm thinking of a situation where output from batteries+PV is more than local demand on the low voltage distribution circuit and the extra is exported to the grid.
Then the medium voltage distribution network sees less load on a step down transformer feeding that section of the grid. If that whole area starts exporting power, then high voltage transmission network sees less load. If there is so much solar that transmission system goes idle, then you are powering your grid by solar alone at that point in time. But solar will not be allowed to be only source on the grid due to requirement to keep spinning reserve on the grid to keep it from collapsing. Now if batteries get so cheap that we have hundreds of GWh of them on the grid and the inverters interfacing them to the grid are designed to be robust enough to not trip offline due to faults on the system (inverter safety tripping in wind turbines brought down South Australian grid recently) we may see the grid shutting down thermal generation sources for days at a time based of solar/wind forecast. We need A LOT of batteries for that.

It probably isn't possible, but my feeling is it could increase congestion since the homeowner is importing energy off peak to store in their battery pack and exporting it on peak instead of more solar being installed in whichever low voltage distribution circuit is still pulling a lot of energy from the grid on peak.

I don't fully get what you are saying here, but there is no difference what source of power is suppying the grid. Solar or battery the current is the same. The batteries have an advantage over solar to supply ON DEMAND power to shave off demand peaks. Solar cannot do that. Batteries will be very useful to supply evening peak load right after solar goes off and into 9pm hour. That will save the homeowner from buying expensive peak power between 5 - 9 pm. Now, if you mean that batteries will create more energy demand then yes. Batteries (Lithium) are lossy storage devices that lose ~15% of the source energy due to cycle and inverter losses. But it does not matter since batteries will be set up to charge off-peak when there is excess generating and transmission capacity on the grid and the prices are low or when you have excess solar generation at noon and you do not want to export that power for various reasons. So no, if setup properly batteries will help avoid power congestion on the grid, not create it.
 
Then the medium voltage distribution network sees less load on a step down transformer feeding that section of the grid. If that whole area starts exporting power, then high voltage transmission network sees less load. If there is so much solar that transmission system goes idle, then you are powering your grid by solar alone at that point in time. But solar will not be allowed to be only source on the grid due to requirement to keep spinning reserve on the grid to keep it from collapsing. Now if batteries get so cheap that we have hundreds of GWh of them on the grid and the inverters interfacing them to the grid are designed to be robust enough to not trip offline due to faults on the system (inverter safety tripping in wind turbines brought down South Australian grid recently) we may see the grid shutting down thermal generation sources for days at a time based of solar/wind forecast. We need A LOT of batteries for that.
Or demand response. A negawatt is as good as a megawatt and all that. The amount of battery storage required also depends on how long it takes to ramp up generators. I don't think CA would need hundreds of GWh of battery backup to safely spin down some natural gas generators, but we still need a lot.
I don't fully get what you are saying here, but there is no difference what source of power is suppying the grid. Solar or battery the current is the same. The batteries have an advantage over solar to supply ON DEMAND power to shave off demand peaks. Solar cannot do that. Batteries will be very useful to supply evening peak load right after solar goes off and into 9pm hour. That will save the homeowner from buying expensive peak power between 5 - 9 pm. Now, if you mean that batteries will create more energy demand then yes. Batteries (Lithium) are lossy storage devices that lose ~15% of the source energy due to cycle and inverter losses. But it does not matter since batteries will be set up to charge off-peak when there is excess generating and transmission capacity on the grid and the prices are low or when you have excess solar generation at noon and you do not want to export that power for various reasons. So no, if setup properly batteries will help avoid power congestion on the grid, not create it.
The difference I'm thinking of is in transmission. I guess an extreme case would be enough PV to complete cover demand during the day, along with enough battery capacity to provide the same amount of energy over a day that could be used to export power outside of the low voltage distribution circuit with the batteries (LVWB).

In that case, the utility transmits energy from large generators to the LVWB off-peak, and then transmits the same amount of energy from the LVWB on peak to some other low voltage distribution circuit, which would increase congestion compared to not allowing exports of off-peak energy from the LVWB and building more PV in other low voltage distribution circuits that the LVWB is exporting to.

I would think that any situation where energy is transmitted, stored, and transmitted again would cause more congestion than energy being transmitted once, or ideally, mostly generated at the point of use.
 
I would think that any situation where energy is transmitted, stored, and transmitted again would cause more congestion than energy being transmitted once, or ideally, mostly generated at the point of use.

I think you're getting caught up on the concept of 'congestion'; The grid is bi-directional but not simultaneously... think more in terms of supply and demand. Each switchyard is an individual 'market'. Almost in a literal sense. Energy exported from homes to lines served by that switchyard won't contribute to 'congestion' it decreases demand and increases supply. Even if power is transmitted twice and stored to offset peak demand the benefits far outweigh the costs.

Demand response is a good first step but it's only going to take us so far. In many ways we've already begun to outgrow it's usefulness. It'll help but it's no where near enough...
 
. Energy exported from homes to lines served by that switchyard won't contribute to 'congestion' it decreases demand and increases supply.
And the same applies at the transformer level downstream of the switches. My excess solar generation gets used by my neighbors who share that transformer and therefore that transformer pulls less current from the switchyard.
 
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I think you're getting caught up on the concept of 'congestion'; The grid is bi-directional but not simultaneously... think more in terms of supply and demand. Each switchyard is an individual 'market'. Almost in a literal sense. Energy exported from homes to lines served by that switchyard won't contribute to 'congestion' it decreases demand and increases supply. Even if power is transmitted twice and stored to offset peak demand the benefits far outweigh the costs.

Demand response is a good first step but it's only going to take us so far. In many ways we've already begun to outgrow it's usefulness. It'll help but it's no where near enough...
I guess I don't understand what you're referring to by congestion then.

So lets say a "switchyard" with a lot of PV and battery backup (SWPVB) stores a bunch of extra energy off-peak. They export that to another switchyard (SW) through the transmission lines connecting them (T1) during peak demand. SW is normally supplied by another generator on a separate line (T2) and both T1 and T2 are usually at about the same percent of their max capacity on peak. Now that SWPVB is transmitting extra energy through T1, it's at it's maximum capacity and T2 is at a fraction of it's capacity. Isn't that a situation where changing how energy is moved around the grid increases congestion?
 
Why do you keep making up unlikely scenarios? Batteries would be placed at the location that draws a lot of power during peak demand, this way alleviating load on the lines feeding that location. Batteries in that way are "portable" and can be placed right next to problematic load.
 
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They export that to another switchyard (SW) through the transmission lines connecting them
Power on the grid is not necessarily exported to a particular site.. It flows in the direction where there is load. Think of it like water in pipes and demand is an open spigot. The source of the pressure, such as a tank at elevation does not determine how it flows. The open spigots determine how it flows.
 
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No.

You're using excess nighttime capacity to reduce daytime load.
Yeah, that would even out generation, but that's not what I was trying to talk about originally. I'll admit to not knowing a lot of jargon, but I guess I don't see how maxing out capacity on one set of transmission lines and minimizing it on another isn't congestion.

Why do you keep making up unlikely scenarios? Batteries would be placed at the location that draws a lot of power during peak demand, this way alleviating load on the lines feeding that location. Batteries in that way are "portable" and can be placed right next to problematic load.
I'm not making up unlikely scenarios, just clarifying my original post. I agree that it isn't likely at this point, but I'm guessing it's one reason why utilities may not be fond of homeowners buying inexpensive off-peak energy and exporting it back to the grid on-peak.

Power on the grid is not necessarily exported to a particular site.. It flows in the direction where there is load. Think of it like water in pipes and demand is an open spigot. The source of the pressure, such as a tank at elevation does not determine how it flows. The open spigots determine how it flows.
I agree. I'm not talking about load though, just transmission capacity/congestion. In my example, there are two pipes leading to a single destination. If the amount of water flowing through one pipe is maxed out and the amount flowing through a separate pipe is minimized, that seems like congestion (something I think an electric utility wants to minimize) to me.
 
I really can't see it happening, simply because peak draw is so high.

If large numbers of people have a battery system that could dump that much power into the grid:
- they wouldn't because the economics of self-consumption would be better.
- celebrate, because we've solved energy
 
I agree. I'm not talking about load though, just transmission capacity/congestion
I don't know how you can have a discussion about congestion without talking about load. The current flows to the load. Capacity is a static thing that is only called up by Cal ISO when there is demand (load). They do have some control over how to switch it to minimize congestion.
 
I don't know how you can have a discussion about congestion without talking about load. The current flows to the load. Capacity is a static thing that is only called up by Cal ISO when there is demand (load). They do have some control over how to switch it to minimize congestion.
I am referring to load, but it's constant at SW in my example. I'm mostly focusing about a change in transmission because transmission capacity constraints could be an issue if owners can export off-peak renewable energy they're stored by scheduling more capacity along an existing line. If transmission capacity is much higher than load, that's probably not an issue because a grid operator can try to minimize congestion, but in times of peak demand, my understanding is that both generation and transmission capacity tend to be lower and the grid operator may be less able to do this.
 
but in times of peak demand, my understanding is that both generation and transmission capacity tend to be lower and the grid operator may be less able to do this
Maybe I am misunderstanding your use of the term "capacity" or I am using it wrong. My definition of capacity is that capacity is static. A transmission line or generating facility has a maximum capacity. Many things run at a fraction of capacity. That is why i do not understand your statement that capacity tends to be lower. Are you saying transmission capacity changes? Please explain?
 
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I gotcha. I'm mostly referencing available transmission capacity. So in my example, both lines have X amount of available capacity to start with, and both are below their maximum rated capacity. After the SWPVB starts exporting a lot of energy through the first list (T1) to SW, the amount of power moving through it results approaches it's maximum rated capacity (available capacity decreases). The available capacity of the second transmission line (T2) increases because now the generator on that second doesn't need to produce the same amount of energy and less power flows through that line.