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It depends on the design, maybe the old generation Roadster was too aggressive trying to maximize peak torque while shifting, hence the transmission at the time couldn't take the torque. The shifting is not to deal with more torque from standstill or at low speed, it is to allow the electric...

Do note that electric field propagation does travel close to the speed of light, so the energy exported from local solar's to the grid do aggregate(with peaker plants and remote renewable sources) and contribute to peak load. So export limiting is self defense from utilities.

BEVs will get their sales and volume, and HFCEVs will get theirs, and this plays out in real time as both encounter their own constraints in their respective stages of deployments, and both are very very far from displacing a meaningful amount of FF consumption. So my guess is that going...

The above arguments have been repeated a few times in the last 2 weeks, but these deep-pocket automakers do have to collect their emission credits or else pay up(dearly). As much as this second round of EVs has taken a long time(100+ years from the first round!) to roll out, hydrogen actually...

In the context of discussing "1 million EVs waiting for excess solar", even when superchargers get renewables, that chunk of electricity still needs to be routed from remote solar through the grid, adding that much stress on the grid. In contrast, if a supercharger can be off-grid with solar...

Well nwdiver asserted that there is no enough curtailments hence there is no need to worry about storage, plus another poster asserted that 1m EVs sitting idle can be used to soak up any excess PV outputs. Both of which are not my assertions.I did participate to point out the holes in their...

This is almost 2 year old. https://electrek.co/2017/06/09/tesla-superchargers-solar-battery-grid-elon-musk/ "CEO Elon Musk said that they plan to deploy more battery and solar systems with the upcoming ‘Version 3’ of the Supercharger, but now he went a step further and claimed that “almost all...

Well how come it is just me off-topic while the other posters also build their cases for/against storage? The discussion of hydrogen as storage is mainly on remote solar farms, not local distributed generators like rooftop solar. From the above quote, It is you what build a case for local...

That is exactly right, but nwdiver argues that curtailment is not to avoid stress on the grid, hence the last few pages of discussion.

Assuming that extra 30MW from those remote farms do not trip a circuit breaker in the grid and cause brownouts/blackouts.

Wrong. There are peak PV outputs(that can stress the grid), there are peak electricity rate hours. Wrong, Curtailed solar power is not excess PV output, because there are curtailed. But the discussion is how to possibly avoid those curtailments, by sucking up the un-curtailed excess solar to...

One can do the calculation to figure out how many square meters locally are needed to charge those 1M cars. But then, that beats the purpose of reducing curtailments at those big solar farms that are recorded by CA ISO, plus the local (non-tallied) curtailments implemented as export limits by...

That is a noble goal, but given how PG&E operates, that is unlikely cost savings will materialize.

Tesla's claim at one point was to take all superchargers off grid and be powered by solar and battery storage, but that has not proceeded that far, meaning most superchargers are still grid tied. Obviously if your EV happens to be close by local solar, the EVs do work as local storage. But...

Again, peak hours are those hours with peak usage, and/or with peak PV outputs. Having excess PV outputs means usage(demand) is not as high, but the excess PV outputs still need to go somewhere, unless the excess is stored locally. Without local storage, the excess PV outputs at peak hours...

Those who pay attention to the verbose descriptions in the article probably may question how a complicated pricing structure(as often championed by utilities?) as described can lead to increased or reduced prices for consumers. E.g. for those who do not charge EVs, how do all these complexities...

The stress matter if the electrical connections between WalMart and your solar are bottlenecks. That has happened around here on and off(and this is the heart of SV), e.g. on heat waves in the last few days, when local loads trip up transformers and fuses.

Again, distributed generation is just a generic term that encompasses rooftop solar, storage, microgrids, etc, etc, that are not grid-tied(at least to the "main" grid). These distributed generators do see their own curtailments, e.g. utilities impose "export limit" to throttle excess PV...

"Peak" in the context of usage as well as PV generation(e.g. hot clear sunny afternoons), both of which puts extra stress on the grid. And in your context of "If there's excess power then by definition that's 'off peak'", for sure this type of 'off peak' at the middle of clear sunny afternoons...

How does charging off peak have anything to do with "1 million vehicles sitting at work, plugged in, just waiting to soak up any/all available excess power"? We were talking about using excess PV output during peak daylight hours to charge 1 million vehicles sitting at work, not off-peak after...

Let's say 7.7kW/car and 1 million EVs, that is still 7.7GW, or 15% extra on top of 50GW peak load in CA the last few years. Let's say excess PV power shows up at peak daylight hours(yes they do), so it looks like you are suggesting that daylight peak excess PV power needs to be stored somehow...

Let's say those 1 million EVs are charged at 19.2kW L2, so that is extra 19.2GW that the grid needs to bear. The peak load in CA's grid is around 50GW the last few years, so you are asking the grid to take extra 40% load, likely causing brownouts/blackouts. If those 1 million cars can be...

The article said the sales price is less than $40k after incentives, that's still not as generous as $10k all-in for those 3-year leases with 20k miles/year, free fuel, free 21-day rentals, free tolling to closest refilling station while inside CA, and free loaners when the refilling stations...

That is what HFC fans say about electrolysis! :)

The chemical hydride supposedly can drop to 1800 psi.

That means your solar roof does not pump all the excess(e.g, a chunk of 13.5kWh per PW2) back on the grid, instead store it off grid. This reduces the load on the grid in peak hours.

In peak rate hours(e.g. today was 100F+ sunny clear afternoon around here) with high demand (e.g. AC), and high supply(e.g. solar at full tilt). The grid is under the most stress at this time. Off grid storage can absorb excess PV outputs and smooth out the load on the grid.

That is the idea of Honda/Toyota/Hyundai and several other countries, apparently they think it is a viable future for them.

PW is off grid and needs to be charged by solar to be eligible for 30% ITC. Solar itself can be off or on grid to qualify for 30% ITC. Powerwall3 should be available soon.

Grid tied solar without storage means when grid goes down, so does solar, probably to isolate the grid while technicians work on it. Solar + Powerwall(PW) means PW is off grid, i.e. PW2 cannot import from nor export to grid. As u said, this probably is enforced by power company to avoid PW...

There is a recent R&D paper about using maganese hydride@1800psi 10.5% wt storage with room temperature absorb and release, leakage may not be too bad compared to 10000psi with pressured hydrogen. The paper does not say if this hydride eats through metal or not.

CA offers 30% of purchase price solar + Powerwall installed at the same time as investment tax credit ITC.

CA provides incentives for solar + storage to go off grid, in order to save the grid. No matter how many times others insist otherwise, no grid = no electricity(blackouts) even for basic needs(let alone BEVs). CA as a state being at the bleeding edge of renewables at state level is learning...

Powerwall installed with solar cannot be charged from grid. People around here use their Powerwall's to soak up daylight for daytime use and then charge BEV at night off-grid with zero extra load. Stored power can become a workhorse in CA esp. with the rooftop solar mandate starting 2020. As...

The Powerwalls solves another important problem, namely, electricity to feed BEVs is offloaded from the grid. Just use CA as an example, it has around 5.5% of cars registered in US, so let's assume CA uses 5.5% of that 10 million barrels a day, or 0.55 million barrels, or almost 1TWh a day...

The fundamental issue with electricity is storage, so that needs to be addressed wisely upfront. There are experiments of solar to heat storage that can he promising, but again billions are needed to play around with sci-fi ideas. It probably does make sense to spend some billions to plant...

Batteries do have its emission foot prints that are front loaded(some said almost 8 years of equivalent ICE driving, others say 2 years) and scaled with capacity, plus daily plug-in. Actually the 1% daily drain should be accounted for in MPGe(but likely not the case). So the 2x efficiency...

My view is still that multiple factors need to be considered, e.g. efficiency, availability, cost(e.g. rare earth + clean-room manufacturing in huge factories versus old school electrolysis), etc, etc. It is a complex dance, and any viable solution(instead of just the current winner) needs to...

We will very likely take on a FCEV lease soon to gain first hand experience. From what is observed so far, Toyota/Honda treats their guinea pigs better than Tesla, and is clear winner for 3-year lease TCO.

Well my own real-world experience with spare OEM 4 and 6-cell lithium ion packs for laptops have not been stellar neither. Your Li* maintenance routine must be stellar.

That was a company named Better Place that had trial runs of battery swapping at Israel and Japan but went bankrupt in 2013 after spending $800m. Better Place (company) - Wikipedia

The reality is that the existing renewables are to offset the current power plant electricity output, e.g. CA now has close to 50% of its usage from renewables. There is no spare renewables to offset existing H2 consumption(e.g. 9 million tons in US), nor to offset existing daily gasoline...

The extra weight does weight down the efficiency advantage of BEVs. E.g. a 75KWh on a Model 3(3814lb) yields 325 miles, while a similar capacity 75 KWh in Model X (5140lb) yields 238 miles, or 35% weight increase has a 27% drop in range. Also, let's say a 75KWh pack weights 1000lb. To double...

LiFePO4 is one type of lithium ion batteries, and while it does have lower discharge/self-discharge than other chemistries, it should still have some self-discharge. Lithium iron phosphate battery - Wikipedia Also phosphate type has lower energy density than cobalt type, but stationary...

What brand is your non-OEM battery? I want to read the user manual of that. Is that custom made to have virtually no leakage current while idle? How much does it cost? That is exactly the point. 18 million barrels a day(US alone), 10 million being gasoline, is huge stress on the system...

My previous post says "plants + solar power can scrub", as in photosynthesis.

One sensible approach will be to focus on clean consumption, namely, do not produce any C other than CO2 such that plants + solar power can scrub, plus produce carbohydrates that probably can be composted into synthetic fuels(albeit not fast enough). Those natural solar plants cost a lot less...

Efficiency is one aspect, but availability is also critical. E.g. when the biggest battery factory cannot go beyond 23GWh per year, without good yields, alternatives need to be explored and funded. Do remember 10 million barrels of gasoline a day in US alone is 17TWh a day. At the rate of...

If synthesized CH4 is easier and cheaper to make and store than H2 then the market will gravitate towards that. It is possible that on local roads there are more CH4 powered cars than H2 ones(no stats on that though). Also my question can easily be changed to "Does 100-mile battery range, plus...

It matters a lot what is on the right hand side, CO2 can be absorbed by plants, while CO and other C variants(if released to atmosphere and not captured) cannot. The real point probably is that too many plants have been razed and nature's cycle of recycling carbon and oxygen (etc, etc) gets...