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Tesla application for an electricity generation licence
- Thread starter pharwood
- Start date
Cnixon
Member
Or....
Tesla quietly adds bidirectional charging capability for game-changing new features - Electrek
Could be playing the long game.
Tesla quietly adds bidirectional charging capability for game-changing new features - Electrek
Could be playing the long game.
A University of Oxford study suggested that it didn't have any significant impact on the battery and might actually be beneficial, perhaps because the additional discharge means that the car sits at lower average state of charge.
ACarneiro
Active Member
If I wanted the battery at a lower average state of charge I would charge it less.
I’m sorry but range is THE one limiting factor with EVs at the moment, with battery longevity a close second.
V2G takes away control of the first with a possibility (the Oxford study is disputed) of sacrificing the second.
With the current tech seems like an obvious no-go, IMHO.
I’m sorry but range is THE one limiting factor with EVs at the moment, with battery longevity a close second.
V2G takes away control of the first with a possibility (the Oxford study is disputed) of sacrificing the second.
With the current tech seems like an obvious no-go, IMHO.
Exactly. For the 'plug in and ignore' user, V2G might make it easier to ease the typical state of charge below 90%, it comes with the reduced flexibility that I'm working with by sticking with 75% SoC during lockdown. For me, V2G is an emergency measure only - implemented with a 12V invertor.
I'm happy to host a grid connected battery in the house (and if I had time, I might look into load shifting some of the baseload), but using new grade-A cells for this doesn't seem to pay off today.
We will allow you to choose what you do with your battery.
Will you allow us to choose what to do with our batteries?
P.S. The range and longevity of current tesla batteries are fine, problem is just their price.
And V2G usage can reduce it.
I wouldn't say not a hope in hell's chance for V2G, although I am a skeptic.
I think that scale and simplicity will always favor dedicated storage on the grid. V2G is predicated on making use of sunk battery and power cost, but it's not free to implement. So, as storage system costs fall, the net value of V2G will decrease.
The problem with customer feed-in, is that to make it worth customers' while, the price to feed in has to be higher than the amount they paid for the electricity, including taking into account round-trip losses, and that price is far higher than typical wholesale power. We see this in the USA, with arguments over net metering, which pays a lot more than the wholesale price.
That high price to consumers will, in my opinion, leave too much margin for generators and utilities to add storage, storing low-value power to sell later into the peak, or to avoid expensive peak power.
However, V2H/V2B is a possibility because it's all behind the meter and provides the additional benefit of power in the event of an outage. As with a generator, there would be a cost to setting it up. But, if you already have solar+storage, or already have a generator, it should be able to be added to the system relatively cheaply.
At the moment, Elon Musk must be rubbing his hands with glee at the wild speculation. He just has to say that they're going to do a presentation on something, and people go crazy.
MrBadger
Badger out
To implement V2H backup would require significant hardware changes to prevent anti islanding - ie to prevent power flowing back to the grid in the event of a power failure - a significant danger to people working on the grid. Without backup protection (not a requirement with V2G and nice to have with V2H), anti islanding could be implemented either in the car, or the wall connector.
Agree on the requirement for protection. All of the pieces needed already exist.
Tesla Gateway wireless reports grid and isolation state to PowerWalls and coordinates mode control and load balancing. Requests for additional power are sent to the Gen 3 wall connector (also on WiFi) which then signals the car to export.
Presumably the million mile battery is a battery whose life is not reduced by charging and recharging cycles.
Given that the battery will be smaller and cheaper too.
If you then add a V2G capability it would be a very clever move.
If Tesla sold the battery seperately to the car, it could reduce the price of the car too.
If Tesla then applied for a licence to supply electricity....
Oh this could be a masterstoke Elon.......
Given that the battery will be smaller and cheaper too.
If you then add a V2G capability it would be a very clever move.
If Tesla sold the battery seperately to the car, it could reduce the price of the car too.
If Tesla then applied for a licence to supply electricity....
Oh this could be a masterstoke Elon.......
Like @ItsNotAboutTheMoney, I just can't see V2anything having much overall benefit. Maybe if a car becomes a complete managed service, owned, insured and operated by a third party, then I wouldn't care what they did to reduce my transport cost, including messing around shunting energy in and out of the battery as long as the range was maintained at an acceptable level.
300 miles range with fast charging is going to be fine for most owners, so if the transport provider wants to provide a 200kwh battery and use some capacity for other purposes, fine. Although wasting energy having the car needlessly drag that oversize battery around and the increased risk / cost in an accident doesn't make sense to me.
Also look at Smart Meters and how long coming and under performing they have been. And unless you have very smart systems, you risk shunting energy back and forth between batteries and wasting quite a lot along the way.
.... and imo that makes far more sense. Don't buy a new car with a 200kwh that you don't really need only to need V2x to make it worthwhile. Just install 50kwh battery / power wall. The regulatory issues of grid connection are not insignificant and its all a hassle for even 20kw of power. Every firmware change would need testing and approval. Now if every location had a bidirectional power connection separate from existing supply, at least the whole thing is separate, and in reality mass charging infrastructure has yet to arrive so there might be something to look at. But it all feels very infrastructure-heavy with relative high install and maintenance costs for a pretty low benefit per connection.
What I had not given much thought to was the problem of maintaining grid frequency. With loads of micro generating kit on the network, all trying to maintain sync with the network, that presumably assumes and requires the 'micro' to be very much in the minority. If you have so much dispersed generation all slaving its frequency to the grid..... made up of a lot of other dispersed generation also slaving it's frequency to the grid...... then I guess you easily end up with the tail wagging the dog as there is nothing on the grid capable of actually holding the frequency. Or may be more like blind leading the blind with slave inverters syncing to other slave inverters.
300 miles range with fast charging is going to be fine for most owners, so if the transport provider wants to provide a 200kwh battery and use some capacity for other purposes, fine. Although wasting energy having the car needlessly drag that oversize battery around and the increased risk / cost in an accident doesn't make sense to me.
Also look at Smart Meters and how long coming and under performing they have been. And unless you have very smart systems, you risk shunting energy back and forth between batteries and wasting quite a lot along the way.
.... and imo that makes far more sense. Don't buy a new car with a 200kwh that you don't really need only to need V2x to make it worthwhile. Just install 50kwh battery / power wall. The regulatory issues of grid connection are not insignificant and its all a hassle for even 20kw of power. Every firmware change would need testing and approval. Now if every location had a bidirectional power connection separate from existing supply, at least the whole thing is separate, and in reality mass charging infrastructure has yet to arrive so there might be something to look at. But it all feels very infrastructure-heavy with relative high install and maintenance costs for a pretty low benefit per connection.
What I had not given much thought to was the problem of maintaining grid frequency. With loads of micro generating kit on the network, all trying to maintain sync with the network, that presumably assumes and requires the 'micro' to be very much in the minority. If you have so much dispersed generation all slaving its frequency to the grid..... made up of a lot of other dispersed generation also slaving it's frequency to the grid...... then I guess you easily end up with the tail wagging the dog as there is nothing on the grid capable of actually holding the frequency. Or may be more like blind leading the blind with slave inverters syncing to other slave inverters.
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MrBadger
Badger out
If you are not directly connected, why do you need to synchronize?
Systems with multiple Powerwalls self synchronize already.
My non-expert but hopefully slightly informed understanding goes this far: (happy for better informed educational responses!)
Unlike DC where you simply increase voltage to increase current & power, AC is far more complex. Imagine three playground swings in a row side by side loosely tied together, two at the ends being pushed and the one in the middle following them. The two end swings represent the grid and local inverter / powerwall / generator and the middle is the loads in your house.
Firstly, for the middle swing to 'work' the outer two swings must be swinging at the same rate as each other and stay in time (synchronization). The inverter swing has to decide on its frequency by following the frequency of the grid swing. The inverter also has to take some / all load off off the grid. Unlike DC, the voltage is always changing magnitude (and direction). In order for the person pushing the Inverter swing to do more work moving the load swing, not only must they stay synchronised but they must push very slightly earlier than the grid swing gets pushed. As long as the effect of the grid swing is potentially very much greater than the Inverter swing (think a much heavier swing) then there is no problem with where in the system your steady, definitive master timing is coming from. Or rather there is an obvious leader, like a huge heavy pendulum that has enough weight to ensure it remains in control!
Now extend the model and imagine loads of inverter swings and loads of load swings. If there is not enough 'weight' in the grid swing, all the Inverter swings can start pulling the timing one way or the other as they think trying to take up some of the load. In such a case the grid swing could no longer be able to maintain a fixed frequency, and things could quickly fall apart.
My question was if there is any purpose or existing or proposed system where the synchronization could be sent separately so generating devices could synchronize to an absolute reference.
Multiple inverters at one location could either have a separate control bus between them or just work independently but that would have some potential issues.
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An absolute reference doesn't help because the generating systems need to react to what the voltage waveform is, not what it should be. Any cumulative drift needs to be ignored while still attempting to pull the frequency to nominal.
This is due to how mechanical to AC generation works. There is an induced field in the rotor that acts on the stator to generate power. This field is not synchonous and you have slip. The amount of slip changes the load on the mechanical side and the power generated. Just like loading a direct fed three phase AC motor slows the rotor and increases the power draw, but doesn't change the stator drive field. So in power generation, a reduction in the line frequency results in more power being placed on the grid. Conversely, higher frequency unloads the generation.
For a powerwall on any other inverter, the current waveform is under direct control. Rather than needing slip to adjust power, they can do it directly. By watching for the zero crossing of the waveform they know which polarity to produce. They then add power boosting the voltage. By tracking the resultant waveform, they determine if they need to reduce output from maximum. They also vary their output current based on the voltage to approximate an ideal source, max positive at 1/4 cycle, zero at half a cycle, max negative at 3/4.
So the inverter doesn't neccessary push earlier, it can push power at line frequency causing the voltage to rise.
In both cases, getting out of phase loads up one source and unloads the other so the system is self adjusting.
That's exactly what I wanted to hear.
So, in that case, why was there a push to get renewable (wind? - but I thought PV too) taken off-line at such a high cost recently? Relating to the mix of generating method?
Is Wind typically rectified and inverted? (therefore looking the same as PV to the grid?
So, in that case, why was there a push to get renewable (wind? - but I thought PV too) taken off-line at such a high cost recently? Relating to the mix of generating method?
Is Wind typically rectified and inverted? (therefore looking the same as PV to the grid?
