Electric vehicles could save billions on energy storage

May 22, 2018, Institute of Physics
Electric vehicles could save billions on energy storage
Credit: Institute of Physics

Using electric vehicles (EVs) as mobile power storage could eliminate the need to build costly stationary grid storage for energy from renewable sources.

That is the key finding of a new study by the Lawrence Berkeley National Laboratory (Berkeley Lab) in California, published this month in Environmental Research Letters.

Using California as a case study, the researchers looked at the issue of large-scale deployment of renewables across the energy , the associated problems of variability (daytime overproduction, or evening surge demand), and how controlled charging of mandated EVs could help to mitigate these problems.

Lead author Jonathan Coignard, from Berkeley Lab, said: "California has ambitious targets to decarbonize transportation, mandating the introduction of 1.5 million zero-emission vehicles (or ZEVs) by 2025, most of which will be EVs. It also has a renewable energy policy requiring 33 per cent of grid energy to come from renewables by 2020, and 50 per cent by 2030."

Co-author Dr. Jeffery Greenblatt, now at Emerging Futures LLC, said: "A substantial opportunity exists if EVs from the ZEV Mandate are used to provide grid storage to support renewables integration.

"By removing the need to build new stationary grid storage, EVs can provide a dual benefit of decarbonizing transportation while lowering the capital costs for widespread renewables integration. These benefits are not limited to California, but are applicable worldwide whenever EVs and renewables generation become widespread."

Using net grid load forecasts from the California Independent System Operator (CAISO), the research team quantified how increasing numbers of EVs would affect the evolving grid load in three scenarios: 1) if EVs were charged in an uncontrolled manner, 2) if vehicles were grid-integrated with controllable charging only (one-way power flow, or V1G), and 3) if vehicles were grid-integrated with controllable charging and discharging rates (two-way power flow, or V2G) for the worst day of each forecast year.

Their results showed that California's storage mandate could largely be met through the ZEV mandate with only V1G-capable vehicles. The finding is significant, as V1G is readily available today with little added cost compared with uncontrolled charging.

Co-author Dr. Samveg Saxena, also at Berkeley Lab, said: "Even more significantly, we found that several billion dollars of capital investment could be saved if EVs are used in lieu of stationary . Those savings could be redirected to further accelerate the deployment of clean vehicles and -grid integration, and could even be used to pay EV owners when their vehicles are grid-connected with controlled charging."

Explore further: Research determines integration of plug-in electric vehicles should play a big role in future electric system planning

More information: Jonathan Coignard et al. Clean vehicles as an enabler for a clean electricity grid, Environmental Research Letters (2018). DOI: 10.1088/1748-9326/aabe97

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dogbert
2.4 / 5 (10) May 22, 2018
If your electric vehicle won't charge because the grid needs the energy first and especially if your electronic vehicles battery it's drained to serve the grid, how happy are you going to be with your electric vehicle?

If you keep missing work or come in late because your car is not charged, how long will you have that job?
dschlink
3.9 / 5 (8) May 22, 2018
There are four distinct periods in power consumption: early morning - high, midday - low, evenings - high, and over-night - very low. Solar peaks in the midday, wind at night. Automobile use peaks in the morning and evening, so if EVs are used to absorb the solar and wind peaks, they will be fully charged for commuting and providing power for evening use. Base generation can cover for days with low solar or wind production.
EyeNStein
5 / 5 (2) May 22, 2018
If you can set your car to only feed the grid as prices reach your chosen premium price then the take-up of this scheme should be better.

(Though with past FIT schemes it seemed only the big enterprises got the top premium rates at peak demand, even if your system had battery storage built in, you received a lesser rate. )
carbon_unit
4.8 / 5 (4) May 22, 2018
I can see how this could work. It is reasonable that EVs that have arrived home could carry excess charge into the evening, making it available to the grid, then recharging overnight, for the right incentives. If trickle charging were offered at most workplace parking spaces, then vehicles could charge in the morning and into mid afternoon without causing grid peaks.
Dogbert's doom and gloom scenario could be avoided by suitable preference settings in the vehicle:
- amount of charge to hold in reserve (never give back)
- amount of charge needed by drive time
- strategies for charging/returning power based on utility energy pricing (there must be incentive...)
- etc.
There would of course need to be suitable overrides, for example if going on a long trip.
Eikka
4 / 5 (3) May 22, 2018
Automobile use peaks in the morning and evening


Not quite.

https://ops.fhwa....orig.jpg

While the traffic -peaks- happen and morning and evening, the traffic in between doesn't go away. It stays at about 80% from the peak through the middle of the day, leaving a great number of the cars unavailable for grid storage.

The proposal also means that all parking spots must be equipped with smart chargers (cost?), and drivers need to be forced to always seek those parking places and plug their cars in for when CAISO needs to dump power. If your EV is sitting in a parking lot without being plugged in, it's no good for V1G or V2G because it isn't connected.

That's still the kind of "do I really want this?" question for car owners. Unfortunately, the way the politics goes, they may not have a choice.
carbon_unit
5 / 5 (1) May 22, 2018
Your chart is kind of what I expected. Peaks in the morning and evening as workers commute. That set of vehicles typically sits at the work destination until quitting time and would be conducive to slow charging between 10 and 4ish. Those six hours could 'top the tank' quite nicely for many. Parking garages and lots could offer access to powered spaces for a nominal extra cost.

I never indicated that such things should be mandated. An employer could offer trickle charging as a benefit or for a very modest monthly deduction. Might not even need smart outlets? Just offer access to 110-vac outlets. I would not care to see behavior mandated, only that the capability to do this be available in terms of standards, defined infrastructure and in vehicles. Let power price incentives make it happen.
Eikka
5 / 5 (2) May 22, 2018
Besides, the main argument of the paper isn't that you can store large amounts of energy in the cars, but that they provide a cheap POWER reserve due to their ability to instantly respond to command. It saves billions because you don't need to run as many load following gas turbines to ramp up and down with the renewables - it gives time for the other producers to adjust their output.

Each individual car can only charge up as much as it has consumed during the day, so the actual storage capacity of the vehicle is rather small. For 15 miles of commuting, about 5 kWh per car.

Unfortunately for the ramping load/supply use, the power ramps coincide with the traffic peaks.
Eikka
5 / 5 (1) May 22, 2018
Might not even need smart outlets?


It will need smart outlets, because the output of renewables during the midday peak isn't guaranteed. There are days when you get a huge dip in net load, and days when you don't, and days when you get a bit of both because the weather might clear right through the middle, and the cars can't just be plugged in dumb to charge regardless or they'd make the situation worse.
WillieWard
1.9 / 5 (9) May 22, 2018
"Study: Electric Cars Actually Increase Pollution" - May 16, 2018
https://www.weste...llution/
"Every green initiative has been a disaster"
Eikka
5 / 5 (2) May 22, 2018
Also consider, what happens when there's been a cold, cloudy/rainy day, and all the commuters have NOT been able to charge at work.

Oh, that's alright, they all just plug in when they arrive at home and... oh dear, things just went from bad to worse:

https://insideevs..._305.png

With an increasing number of EVs, the utilities will have to start limiting charging at evening/night as well. All in all, it seems that this isn't a situation you can "win", except by buying a bigger (more expensive) battery and charging it up whenever possible to make sure you're not stranded because of load shedding.

That graph btw. shows why the smart chargers are a boon to utilities - notice the perfectly straight and level ramp at night: that's the utility staggering the chargers to create the demand they want. The rest of the curve is people switching their chargers on regardless of the utility's charging plan, with a peak around 9 pm.
tpb
5 / 5 (4) May 22, 2018
If you are charging and discharging your batteries for grid use you are degrading the batteries.
Who pays for early battery replacement in your car.
Eikka
5 / 5 (1) May 22, 2018
Another trick that can reduce demand for energy storage is simply turning all the solar panels to face west instead of south.

https://cdn.app.c..._-05.png

But that requires changes in the subsidy structure, which currently rewards people for producing the maximum amount of energy regardless of whether it fits the grid.
Eikka
5 / 5 (5) May 22, 2018
If you are charging and discharging your batteries for grid use you are degrading the batteries.
Who pays for early battery replacement in your car.


The utility of course. It's just another load following powerplant from their point of view.

$200 per kWh at current prices, divide by 2,000 cycles = 10 cents a kWh or $100/MWh. That's cheap compared to peaking powerplants which in the worst cases can run up to $2000/MWh.

All the larger powerplants can only ramp at limited rates. Let's say you have a poweplant that can ramp at 10 MW/min and you expect the load is going to reduce by 200 MW in ten minutes. You have to start reducing output 20 minutes in advance to reach the -200 MW load condition in time, but while you're reducing output you need to bring other generators online to make up the difference. Same thing in reverse going the other way.

This is peaking power, the most expensive type because it consists of simple once-through gas turbines and diesel generators
carbon_unit
4.5 / 5 (2) May 22, 2018
If you are charging and discharging your batteries for grid use you are degrading the batteries.
Who pays for early battery replacement in your car.
Good point. Any incentive system must take this into account and compensate for the extra use.
Eikka
5 / 5 (3) May 22, 2018
The reason it's called peaking power is because it follows the derivate of the load curve. That makes the output "peaky". It's not just for the highest power demand of the day - it makes a "blip" whenever the load changes up or down - and that's part of the reason why it is costly: the expensive turbines and engines only get to run for a limited amount and run idle otherwise, so the fixed costs per output energy are greater: the money has to be made on a smaller number of kilowatt-hours.

The most expensive kind is the backup power that may see use once a year, when the backup reserve of other powerplants runs out.

V2G schemes can pay off in both of these cases. You can pay a good profit to car owners for providing a ramping power reserve, but for energy reserves (load following/baseload) batteries are still too expensive because they add to the cost of energy, e.g. $50/MWh + $100/MWh = triple the cost of power.
Eikka
5 / 5 (1) May 22, 2018
Then there's also the case of reactive power. In a power system, there's all kinds of loads which react differently to the voltage waveform of the AC power. Ideally all loads should draw more current when the voltage increases and vice versa, but motors, power converters etc. distort the relationship (called the power factor) and lower the power quality. This leads to instabilities, which shows up as wild voltage spikes/dips and spurious currents that heat up transformers and power lines, losing power or even breaking equipment.

A number of batteries with smart chargers on the grid can shift the power factor closer to ideal by drawing current from, or returning it back to the grid on a millisecond timescale in sync with the AC waveform to compensate. They can charge up the battery on the part of the AC cycle when other devices aren't, or returning it when other devices are drawing more than normal, thus stabilizing the grid voltage.

This is also a valuable service.

carbon_unit
not rated yet May 22, 2018
Might not even need smart outlets?
It will need smart outlets, because the output of renewables during the midday peak isn't guaranteed.

I was envisioning dumb 110vac outlets off of the grid. Nothing fancy. If the grid is primarily renewables powered at that time, great. If not, well, the cars still need to be charged. (Yes, some opportunities to be optimal may be missed in exchange for simplicity/low infrastructure costs.) Irrespective of energy source, the power delivered during morning to mid afternoon will reduce power needed later, reducing the peak usage later in the day. The increased carry-over power could be made available to the grid during during peak.

To avoid small peaks, the dumb trickle charge outlets could be managed slightly, to phase turn on and maybe do some modest duty cycling/load shedding if required. They might be guaranteed to be on only 80% of the time during the day. Ten minute outages on rotating sockets if demand was too high.
Eikka
5 / 5 (1) May 22, 2018
If the grid is primarily renewables powered at that time, great. If not, well, the cars still need to be charged.


Well, the main problem is the power ramp. The cars should be connected in a staggered fashion to match that. This doesn't happen by just everyone plugging them in when they arrive at work, because that produces a large swing upwards in the net load over a short period of time that may or may not coincide with the large swing downwards produced by the renewables. The amount of overlap determines whether the effect is better, neutral, or worse, and the overlap changes throughout the year and day-by-day.

If the renewables aren't there, you get a similiar undersupply condition, which costs you money to deal with because the swinging portion in the middle of the day cannot be reliably met by regular load following.

But the phase-in-out method is viable. A simple timer should do.
Eikka
5 / 5 (1) May 22, 2018
They might be guaranteed to be on only 80% of the time during the day. Ten minute outages on rotating sockets if demand was too high.


This is already used in places where cars need block heaters to start in the winter. The power is on 15 minutes per hour in a staggered fashion, so the entire parking lot of cars draws 1/4 the power. This is exactly to prevent the kind of situation where people turn up at work at 8 am, everyone plugs in their cars, and the load suddenly increases over a ~30 minute period.

However, EVs need more power to charge than block heaters do. Just the charger itself may use significant power, for example in a Model S the "phantom" power draw was 1.4 kW just sitting still before they made a software upgrade to turn the DC-DC converters off when the car was "off". (It is never truly turned off)

antialias_physorg
4 / 5 (4) May 22, 2018
If you are charging and discharging your batteries for grid use you are degrading the batteries

This is one of those myths that dones't seem to want to die. No, car batteries do not degared with moderate charge and discharge. They age due to *rapid* charge and discharge (fast acceleration, supercharging and high voltage outlets) . If you use them to buffer the grid and limit the charge/discharge current and limit the charge region of the battery at which this happens then there is no degradation.

Currently wind energy is present in abundance at night to the point where this is sometimes being sold at negative price. (While output tends to drop at night energy usage drops a lot more between 11pm and 5am). People might even get paid to buffer the grid.

With headlines like these for the 50m battery storage unit in Australia it's easy to see how:
http://www.eurone...two-days
granville583762
3.4 / 5 (5) May 22, 2018
Share your full battery and you will run out to a flat battery
Brilliant kill the electric car before it even starts, we do not share are full petrol tank so whats the difference with a electric tank, you rush out to get in your car and all the nieghbours have been sharing your petrol tank who pays to fill it up, is their a mental blockage that the flow of electrons causes brain cells to seize up, and how you supposed to get to work to pay for people draining your battery pack.
WHO PAYES YOU TO CHARGE YOUR BATTERY AT THE MAINS, how philanphropic of you to work every god given hour to pay other people to drain your battery and leave you to up pick tab the for an overworked battery and a big electricty bill - what a weeze!
granville583762
4 / 5 (3) May 22, 2018
Every IC car fills up at garages, you cannot share a full battery you have charged up at garage, it is no different charging at home and it goes without saying charging outlets have the capacity to meet demand - ask you self how many people fill up their tanks at a typical garage in a day and that is how many electric cars will fill up every day.
granville583762
5 / 5 (2) May 22, 2018
If electricity is free at the point at use, it is feasable to share batteries! But as electricity is not free at the point use of use, no home owner is going to entertain the idea! including every one at the momet is settig forth its good points will be draw the line when BILL drops on every ones mat with a hefty surprise .
david_king
3 / 5 (1) May 23, 2018
At some point, perhaps even now most electric cars will be fleet vehicles and not parked at people's homes. Fleet owners will have contracts with utilities that manage whatever needs to be managed. Soon enough induction chargers will be inlayed into parking spots and even into special charging lanes on Interstates etc. The urban grid will be made up mostly of cars which will be connected most of the time.
humy
5 / 5 (1) May 23, 2018
The premise of this link may be rather flawed because it is assuming the cost of energy storage will stay the same; costly.
But the costs of energy storage are coming down all the time and, once magnesium-sulfur batteries and/or flow-batteries are finally fully developed for mass production, energy storage will become dirt cheap and cost would cease to be an issue for energy storage.
...and this isn't even to mention the supergrid that potentially would eliminate the need for special energy storage (for electric supply) in the first place!
betterexists
1 / 5 (1) May 23, 2018
Let Guys with appropriate keys go to parking lot or driveway based on the reading transmitted, push charged one from the left, take the discharged/about to be discharged one on the right AND LEAVE ! CALCULATE EVERYTHING AND BILL THE CUSTOMER ! Use Appropriate Software Application. It need not be his own Battery !
EyeNStein
4 / 5 (1) May 23, 2018
Some smart hardware and software may well save a few billion; but it will be dwarfed by the capital cost of installing the major power infrastructure upgrades when EV's become popular.
Its still a good idea though to plan and think this way now, rather than too late when other solutions have been built into concrete.
(As long as you factor in the major variances like school holiday migrations!)
antialias_physorg
3.7 / 5 (3) May 23, 2018
Share your full battery and you will run out to a flat battery]

That's BS. You have full control how much of your battery you share. 99% of the time you know exactly what kind of trips you'll be making the next day. With 500km in the battery and an average trip of 40km per day you can easily share 200km worth of battery and still have plenty to spare for any unplanned trips.

The last time you suddenly had to make a 500km trip in a day that was totally unplanned was...never.

ask you self how many people fill up their tanks at a typical garage in a day and that is how many electric cars will fill up every day.

Nope. Almost everyone will charge at home or at work or at the supermarket. The number of highway charging points you actually need is pretty low - and those are quickly set up. they're no more than glorified outlets.
granville583762
4 / 5 (3) May 23, 2018
FREE ELECTRICITY the dream of fusion
When you plug your electric device, mobile, Hope R4+ Vision LED bike lights, tablets and any item with a battery is a storage device for the national grid. This is a brilliant idea - everyone's plugs their mobile in any charging device and the storage capacity potential is enormous.
Even better, the new wireless charging devices charging on the move creates billions of mobile storage capacity - no need to plug your mobile in any where FREE ELECTRICITY on the move.
I do not see BT or VIRGEN as free wither the wireless network so why with BRITISH GAS ELECTRICITY.
Which is why it is cheaper to charge at home through the none storage none sharing chargers now coming onto the market.
granville583762
3.7 / 5 (3) May 23, 2018
Who is paying?
For you to have the privilege of sharing your battery all the electric utilities were all signed up to for our house hold electricity will charge extra for the privilege.
We buy electricity from BRITISH GAS then store it in our devises then make it available for sharing for FREE; I think that will go down well with WALLET. Well it will go down well with the utilities because when you have shared all your electricity you will go back and buy more!

If you store and share back to your utility, you can only convert a lesser percentage of the electricity you just bought back to grid. YOU CAN NOT PUT 100% BACK. Straight away you have made a loss on your investment, it cost more to buy the electricity than you would get, if your utility paid you to put it back, because of loss's you have, you have less to sell back.

To make this work in the free market is simple – I pay you less than you pay me to sell it you in first place!
TheGhostofOtto1923
5 / 5 (4) May 23, 2018
Either vehicle storage or stationary storage - why not both? What about redundancy as a national security issue? Would your vehicles get drained and unusable just when you might need them for evacuation?

This is especially true in CA, land of pending natural disasters. Make the system with layers of backup for safety.
antialias_physorg
5 / 5 (4) May 23, 2018
For you to have the privilege of sharing your battery all the electric utilities were all signed up to for our house hold electricity will charge extra for the privilege.

Would you mind rephrasing that into an english sentence? You know: words with meaning in a correct syntax? it#s the prerequisite so people can actually understand what you want to say.

We buy electricity from BRITISH GAS then store it in our devises then make it available for sharing for FREE

Who said anything about "for free"?
We can either be paid directly by the energy provider or indirectly (because if we don't store the stuff they have to build dedicated storage - the price of which will be added to your utilities bill)

YOU CAN NOT PUT 100% BACK.

So? Do you think hydrostorage is 100% efficient? Or what happens when nuclear/coal powerplants produce more than is currently needed? That isn't stored at all - THAT is 100% lost (100% of which YOU also pay on your utilities bill).
Eikka
5 / 5 (4) May 23, 2018
This is one of those myths that dones't seem to want to die. No, car batteries do not degared with moderate charge and discharge


No. THAT is a myth. Any time you put current through a battery, side reactions happen and part of the active materials are trapped out of use. The issue of rapid charging is a different question, because you also have excessive internal heating and overpotentials due to internal resistance, which causes different chemical changes.

https://endless-s...ioration

Below about 1C charge/discharge rate, the differences between fast and slow charging diminishes. In other words, if you're already taking hours to charge full, even doubling the charging time isn't going to do much anything to the cycle life. A kWh of energy put through the battery is going to damage the battery approximatelly the same amount, fast or slow.

Lithium batteries do NOT get "infinite cycle life", by charging them extra slowly.
Eikka
5 / 5 (2) May 23, 2018
The cycle life of a lithium battery is mainly a factor of its internal voltage and temperature. With the cell sitting at a higher voltage (and higher temperature), more unwanted side reactions happen. In other words, if you never charge your battery full, it lasts longer, but then you have less of a battery to use (more $$$ per kWh)

Faster charging also causes a voltage rise inside the cell (overpotential) due to Ohm's law (V = RI) and the speed at which the charging reaction can happen, which is dependent on temperature. Trying to fast charge when the battery is at 0 C will hurt it a lot, likewise at over 40 C because the voltage potentials needed for the side reactions are reduced and they start to compete with the charging reaction.

If you want to make your typical cheap lithium battery last something like 2,000 cycles, you already have to "over-provision" it by about 40% by not charging it to full voltage, and always charge it slowly.

That's the state of the art.
granville583762
5 / 5 (2) May 23, 2018
granville583762> We buy electricity from BRITISH GAS then store it in our devises then make it available for sharing for FREE

antialias_physorg> Who said anything about "for free"?
We can either be paid directly by the energy provider or indirectly (because if we don't store the stuff they have to build dedicated storage - the price of which will be added to your utilities bill)

I also said nothing about getting free, it's just apart from myself no one else mentioned the cost, your responding to others comments, and yes constant charge discharge wears out lithium–ion batteries.
granville583762
5 / 5 (2) May 23, 2018
Running batteries hot, past their design limit.
Which when everyone purchases their shiny electric TIGUANs, they will suddenly realise a full charge does not get you those 300miles, but 200miles and diminishing, that can only be made up by using it immediately on charging. And to further complicate matters if the manufactures drain the batteries faster than their design they will get hot which I know from experience does lithium-ion batteries no favours at all as they go flat.
Eikka
5 / 5 (2) May 23, 2018
Another common myth is that lithium batteries, in "moderate use", exhibit linear degradiation. In other words, when the battery is past 80% its initial capacity, it still has a long long life ahead until it's truly dead.

Not so.

http://batteryblo...les2.jpg

That graph represents a cell charged up to 4.2 Volts in 2 hours and discharged in 2 hours. For example, a 24 kWh electric car battery charged up in two hours and then driven around at 40-50 mph for two hours. Rinse and repeat.

The 80% from starting capacity point occurs at cycle number 850, and 50% capacity point occurs at around 1150 cycles. Beyond that, full end of life is just 100 more cycles and it's done. The "long life ahead" to 50% was actually just 35% more charges.

In miles, this battery would reach 80% capacity in 85,000 miles, and 50% capacity in 115,000 miles, being effectively dead thereafter.
granville583762
5 / 5 (2) May 23, 2018
The hazards of sharing the battery
When the lithium-ion batteries age they start losing their charge to 50% and lower, you develop a knack of knowing how soon to the point of using and the miles you can get. Where if it is charged a few days ago go then used to day it will leave you stranded and that is without sharing your battery, which by the way I would not advise if you like nipping out in the car, because you remember what was in the battery before tea time and the kids come home thinking they can go to the shop in the car but some dopes been sharing the battery!
Eikka
5 / 5 (2) May 23, 2018
In the above example, increasing the battery size to 50 kWh would more than double the miles, but keeping the charge levels and charging power the same, would not double the cycle life. The charging/discharging rate would be halved, but this does not result in a corresponding doubling of the cycle life because you're already well below the 1C rate which is considered "slow".

However, for very large batteries, 50 kWh and up, the mileage is almost inconsequential - you can't exhaust the battery cycles by driving it before the battery rots out of old age. Therefore you do have capacity to spare for V2G uses - with the caveat that when the battery is starting to degrade by old age around year 8-9, the effect of cycling is amplified and results in a sharper decline to EoL.

That's because nearing the end of life, the internal resistance of the cell grows and this causes the overpotential in charging to grow. To maximize lifespan, the battery should be charged slower as it ages
granville583762
5 / 5 (2) May 23, 2018
Eikka> Another common myth is that lithium batteries, in "moderate use", exhibit linear degradiation. In other words, when the battery is past 80% its initial capacity, it still has a long long life ahead until it's truly dead.
Not so.
http://batteryblo...les2.jpg
That graph represents a cell charged up to 4.2 Volts in 2 hours and discharged in 2 hours. For example, a 24 kWh electric car battery charged up in two hours and then driven around at 40-50 mph for two hours. Rinse and repeat.
The 80% from starting capacity point occurs at cycle number 850, and 50% capacity point occurs at around 1150 cycles. Beyond that, full end of life is just 100 more cycles and it's done. The "long life ahead" to 50% was actually just 35% more charges.

We are starting to see the battery cycling going on during battery sharing and the it effect it has on battery life
granville583762
5 / 5 (2) May 23, 2018
If you have ever used Hope R4+ Vision LED bike lights they have increased the length of time needed to charge the batteries where the batteries stay cool at all times where the 2000 LUMEN LEDs get to hot to touch unless cooled by air, they have made them flicker to fast to see to prevent the LEDs melting, these by the way are in a class of brightest bike lights in the world made in Barnoldswick near Skipton and are the highest quality bike lights in the world, where even hopes expensive batteries charging once a day every day succumb to lithium-ions inability to hold a full charge after a year where we're not talking of constant recycling as in car sharing batteries.
Eikka
5 / 5 (2) May 23, 2018
And you also have to remember that in a large battery such as an EV battery with 8,000 individual cells, the lifespan of the whole battery is determined by its weakest cell. With random process variation in manufacturing, unless you painstakingly measure and select each cell to be equal (more $$$) you can be damn sure that the whole battery performance isn't going to be all that great.

Fortunately, the cells are arranged in modules which can be individually monitored, so the situation isn't competely unmanageable - the software can detect a weak module, and the services can replace it, but, replacing a new module into a well-worn old battery is a waste of money because the battery is going to die soon anyhow, and it causes potentially dangerous balancing problems.
granville583762
5 / 5 (2) May 23, 2018
This rules out Battery sharing
Eikka> Fortunately, the cells are arranged in modules which can be individually monitored, so the situation isn't competely unmanageable - the software can detect a weak module, and the services can replace it, but, replacing a new module into a well-worn old battery is a waste of money because the battery is going to die soon anyhow, and it causes potentially dangerous balancing problems.

This is what HOPE does with its 4cell batteries, its electronics monitors the charging so each cell fills up equally, then it has 3 stages where it drops the battery level from 2hrs on 3 then 2hrs on 2 then an hour on 1 so the battery never lets you down as you can see clearly in pitch black on stetting one - which actually is how car batteries have to be structured to always get you home which rules out battery sharing
antigoracle
1.8 / 5 (5) May 23, 2018
LMAO...
The complete and utter bullshit "solution" to the AGW Cult's pathological LIES. This makes their idea of bio-fuels from food crops, absolutely "brilliant".
WillieWard
3.4 / 5 (5) May 23, 2018
Poor families are so happy helping the rich eco-nuts to pretend they are green.
"Electric Cars are Mostly for Wealthy People, and You're Subsidizing Their Purchase" - May 22, 2018
https://www.ameri...urchase/
ZoeBell
May 24, 2018
This comment has been removed by a moderator.
antialias_physorg
3 / 5 (2) May 24, 2018
It's nonsensical to believe, that if you buy an expensive car (this one which cost you more during its lifetime), then you're saving nature.

Funnily enough, if you do the lifetime cost calcs then these seemingly 'expensive' EVs actually come out cheaper than a comparable conventional ICE car. Even though you pay a hefty extra price up front just adding up all the money you save in terms of maintenance, repairs and fuel costs more than offsets that.
You don't need your own solar panels on the roof (but if you do...boy can you save some serious cash!)

If you want to add 'soft' advantages (like never, ever having to make extra trips to a gas station) then things start looking like a no-brainer.
Eikka
5 / 5 (3) May 24, 2018
Funnily enough, if you do the lifetime cost calcs then these seemingly 'expensive' EVs actually come out cheaper than a comparable conventional ICE car.


I don't believe you, since the lifespan of the EV is half that of a regular car, and you still go through brake pads, shock absorbers, tires, brake fluid, coolant fluid, water pump bearings, u-joints... etc. which wear out just the same.

Of the top 10 list of common faults in cars requiring expensive maintenance, 1st is a worn-out gearbox, the 2nd is electrical faults. The most common reason why cars fail MOT inspection is worn out and loose steering/suspension and brakes, and in older cars rust of course.

What you save is the annual oil change and the occasional timing belt swap, but other than that an EV is going to have approximately as many problems, especially when there's no point in designing them to last more than the life of the battery.
Eikka
5 / 5 (2) May 24, 2018
By year 10 the center dash infotainment console will be obsolete like some in-car phone system from the late 90's and needs replacement...

All said and done, if people are going to scrap the car at year 10-12 rather than buy a replacement battery that is worth more than the car by that point, it's a total waste to engineer the car itself to last 20+ years. Cheaper materials will be used, thinner steel, non-replaceable parts... because it all saves money from the manufacturing point of view.

How cars typically go is, one guy buys a new car, drives it for 3-4 years, sells it on. The other guy drives it for 3-4 years, sells it on... etc. so the cost of the vehicle is spread over multiple owners since most people can't afford to buy new cars. The re-sale value of EVs is lower because of the battery issue, so the first owners are paying more. That needs to be offset by lowering the cost (quality) of construction of the EV to make it worthwhile.
MR166
3.7 / 5 (3) May 24, 2018
Using your property to power the grid is just a hidden tax. It also assumes that every car will be plugged in when not in use. Also the costs of wiring city streets for chargers at each parking spot will be huge as will be the costs of vandalism in many areas.
ZoeBell
May 24, 2018
This comment has been removed by a moderator.
Eikka
4 / 5 (5) May 24, 2018
You don't need your own solar panels on the roof (but if you do...boy can you save some serious cash!)


Actually, that's dependent on what sort of subsidies they're paying you for the solar power. It depends on what price you get for selling it out. Without the subsidies, the payback for your solar panels may be 30 years to never, and so you don't really save anything.

MR166
3 / 5 (2) May 24, 2018
Remember that power availability has to be configured for worst case conditions not the average. Thus if you have a heat wave during commuter drive time you still need fossil backup generators and these must be paid for even if they are not used as often or to capacity. Thus peak spot prices will go through the roof. The only savings will be in average fuel costs since you will still have to pay for employees and maintenance.
ZoeBell
May 24, 2018
This comment has been removed by a moderator.
antialias_physorg
5 / 5 (1) May 24, 2018
Just the replacement of Tesla 85 kWh battery would cost you 45.000 USD or more

That statement makes little sense.
a) You have an 8 year guarantee on the battery
b) Li-ion battery prices have been dropping almost 20% every year since 2011
c) All the data so far says that batteries far outlast the lifetime of an EV (i.e. are much less likely to need a replacement than a motor or a gearbox on an old type of car )

So arguing that "replacing such a battery now is pricey to the end-user" is completely irrelevant.

(BTW: the official quote for replacing a battery by Tesla was 20-25k in 2015...not 45k. But since no one has yet had to pay for this, what's the point?)

Cars with range over 100 miles cost 70.000 USD or more.

What are you talking about? The Model 3 has 220 miles in the base version (35k$) and 310 miles in the long range version (44k$)...before incentives.

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