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Did EVERYTHING just change??????
#1
So I am in the early stages of building my own powerwall.  Thanks to all of you for valuable information on this site.   My project it taking a little while because....lets face it.... I do things the hard way for the sake of fun.

I will still build my wall.  Its actually in the early stages and moving along slowly but surely.  Testing cells, 3D printing cell holders, preparing a network rack for containment...

The Change:

On November 21st, within minutes of the unveiling, I ordered a CyberTruck.   I think this may be a game changer.   This is a huge powerwall on wheels!  They have not released the actual battery specs yet.  But, what do you think?  100KWH???   I'm guessing on that.....   The truck is going to have 110/220 outlets on it.  Unknown amperage rating on the inverter but Elon did say it is for tools.  So 15 amps at least.... Probably 20.

Now I am thinking that my home powerwall should be nothing more than an energy storage buffer.  Get about 4000 watts of solar panels, a 3000 watt Victron inverter, and have about 10KWH powerwall storage buffer just to charge the truck.

Just to so everyone understands, I live in a household with 2 driving adults.   We already have 2 practical internal combustion vehicles.  The CyberTruck is intended to be a 3rd vehicle that spends most of its time in the garage.  So charging at a slow rate is a non-issue.  It would be used whenever a truck is required, and for travel when the 6 seats are needed (we have 4 kids combined).

What do you all think?  Game changer?
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#2
I think that if you have an EV it should be your primary transport vehicle.
If the EV is home a fair bit charge it straight from solar rather than using solar to charge a battery to then charge the car.

It’d be a shame to have an EV & solar and do most of your driving in an ICE vehicle.

We have a Kona EV and a Zappi charger that lets us charge direct from solar (AC coupled), just ticked over 15,000km in 5 months.
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#3
Jon, You just introduced me to the Zappi. I am going to read up on that a lot more.

Right now we drive a Hyundai Santa Fe and a Hyundai Kona (both ICE). The CyberTruck will possibly be our first EV. But, because production will not start until 2021+, it may end up being our second EV. Not sure yet. If money works out the way I would like it to, there could be a Model 3 or Model Y thrown into the mix first. Either of those would replace the Santa Fe. I drive the Kona to work and my business owns it.

I have been looking at the Kona EV as well. But the charging network in my area for the Kona would be terrible. I really need to be able to use the Tesla charging network.
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#4
No, not game changer. There are several who are now using their EV to help with power needs. Tho, it's usually there to supplement, not primarily deliver the power.

I think there's a few on here that have done this. And I believe for a long time, some of the EVs wouldn't allow it. Then there was a software update that allowed for higher amp output or something. Maybe that was Tesla, not sure.

However, buying an EV specifically for being a powerwall on wheels is VERY expensive and wasteful all around. As Jon mentions the EV should be used for transport, not powering the house. Now, using it out in the woods as a portable powerwall, that'd be nice.
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#5
Buy a brand new vehicle just to store it in the garage? That's got to be a first world problem! Haha! Even if it's possible, I don't know how I'd feel about degrading a EV battery so that it's basically a useless vehicle in 10 years, requiring a complete battery replacement costing more money than it's worth.

The biggest things with EV is that you can't charge it at work, but it doesn't benefit from sitting at home all day either. PV production is during the day when you're at work, so it's a waste to discharge a powerwall to charge a ev during the night and doing unnecessary cycles and degrading the battery. I thought about this for a bit as well, and the only way to see maximized benefit is to use two vehicles. I was thinking about getting two used PHEV vehicles, like a used Chevy Volt, so one stays charging during the day while the other is being used. I like the Kona because it's a hatchback/wagon type and can haul quite a bit.
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#6
2 totally unrelated pieces of info;

If you want a big battery it’s cheaper to by a Kona EV in Aus than it is to buy the equivalent kWh in a powerwall.

Battery degradation in utilising an EV battery for home supply will be negligible I believe, both the charge/discharge rates will be very slow and the depth of discharge will be very gentle compared to driving the vehicle,
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#7
Am I the only one that finds the new Tesla CyberTruck *really ugly* - like so ugly I could never buy it? I'm a complete fan of Tesla, so I don't say that with any autonomous - its just ugly/disappointing to me.
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#8
The truck will have something like 200kWh of battery for the 500 mile range version.

From Muks comment of million mile battery life (new cells next year) and the 500 mile version implies a cycle life of around 2,000 to start with and the test data shown earlier seems to support the multi thousand cycle life..

The socket for "power tools" would need to be minimum 3kVA and with the poresentation of the electric quad charging 2kVA would be an absolute minimum that would be of any use.

The option would be to use the truck as a reseve battery and not a main battery for a powerwall (dump excess energy in and discharge only when you really need to) and use a separate powerwall to take all the main charge/discharge cycles.

First issue is Musk has yet to build his new battery factory to produce the cells for the truck and pickup..... this is the critical delay.

Oh... use LTO cells for your main powerwall and cycle life is not really an issue.... :-)
If you can't quantify how much they cost, it's a deal, I'll buy 5 of them for 3 lumps of rocking horse ......
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#9
I really should have set the context better Wink

I live in hurricane ally (southeastern NC). My primary objective for a powerwall or equivalent energy storage is for use during power outages for essential loads....like the fridge/freezer at least part time, fans when needed, and charging kids electronics so they don't drive us insane. Essentials.... lol

My secondary objective is to mess around with small loads. Maybe power my workbench in the garage. Perhaps a windows unit AC sporadically to cut back on the crazy summertime electric bill on super hot days. Planning to charge the powerwall on only solar so the powerwall energy is free (sort of).

So my thought was that the Cybertruck can probably provide power to a full size refrigerator for what???? A couple of weeks? More than I would ever need. And am betting its inverter is bigger than I would ever want to purchase as a stand-alone item. Its changing the way that I am looking at this entire project. So now I may be more focused on providing solar energy to the truck vs. focusing on peak amperage draw capability from the powerwall. More solar panels and less batteries.



To answer some of the other comments...

I am buying the truck as a truck 1st. We have 2 SUV's. Neither are well suited for hauling plywood or lumber over 8 foot. I can say I have successfully moved 8 foot 2x4's in the Kona but I am sure I look like an idiot doing it. It is front glass to back glass. This happens often enough that I want some kind of truck. I considered buying an old beater just for this purpose.

When all 6 of us currently travel together we have to drive both vehicles. That is just......stupid. I believe the Cybertruck will seat 2 adults and 4 kids pretty comfortably. The skinny little kid in the center front seat gets VIP access to the screen. A good trade-off if you ask me.

I have a long commute of 80-90 miles per work day. I am a partner in my company and we purchase vehicles through the company to drive. The (ICE) Kona is only 1 year old, and is my vehicle to drive for work. It is a cheap vehicle and rather practical as far as fuel economy.

My wife drives the Santa Fe and only has a 15 mile commute per workday. She would be the best candidate to drive an EV, but I don't see her wanting to drive a CyberTruck on her own unless the weather conditions are bad, or zombies are on the loose. She actually wants a Model 3/Y, but is perfectly ok with me buying the truck. (I am fully aware of the reality here. This means that I do in fact owe her a Model 3/Y to be delivered ASAP. lets just hope crypto sees a big boost in 2020)

OffGridInTheCity, I understand what you are saying. As a Tesla/SpaceX fanboy, I eagerly watched the live-stream, and my first impression was WTF, this is a joke, bring out the real truck..... But 30 minutes later I placed the pre-order. I went for the middle, dual motor model. Its just so much tech for the $50k price tag. Its just too much...... And as I stare at it I wonder if it is really ugly or just different. And are trucks really good looking? No, I think trucks are actually boxy and ugly They are big, square, and utility. Cars are pretty. The cybertruck is just a different kind of ugly Smile But you know you secretly like that singular headlight and off-road light. GMC/Chevy/Ford/Nissan/Toyota will copy that in the next 2 years.
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#10
(12-03-2019, 07:21 PM)Jon Wrote: 2 totally unrelated pieces of info;

If you want a big battery it’s cheaper to by a Kona EV in Aus than it is to buy the equivalent kWh in a powerwall.

Battery degradation in utilising an EV battery for home supply will be negligible I believe,  both the charge/discharge rates will be very slow and the depth of discharge will be very gentle compared to driving the vehicle,

I've been looking into Leafs, so I'm surprised that there isn't a bigger EV market in Australia. According to wikipedia there's only around 1000 Nissan Leafs out of a total of 250,000 sold.

Your comment about degradation got me thinking... Using some really simple maths (and do correct me if I didn't get it right!!) I use a Leaf that has a 24kwh battery, of which around 75 miles range which is to be expected. Assuming it's not depleted all the way and only 80% is used, so around 19kwh is consumed. That means per kwh it can travel around 3.9miles. I average around 30 miles a day, which consumes around 7.6kwh daily.

My powerwall currently consumes 15kwh per day during the winter. So by using an EV as a powerwall would put a bigger burden on any EV than I would actually do to it while driving.

If you'd think a Tesla doesn't suffer just because it's got such a huge battery, a Tesla Model S has a 250mile range (i think?) and a 85kwh battery?. Most people don't drive 250miles per day. If they do then they would be putting 50,000+ miles per year. I'd not want to touch any Tesla that has 200k miles after 4 years. But going with the same math, 85kwh minus 20% would be around 68kwh for 250miles. That puts it at 3.6 miles per kwh. About the same as a Leaf in efficiency. So driving it would put less than 10kwh per day if you travel less than 40 miles per day. Still less than what a powerwall would consume. There are of course other factors such as heat and stress that a powerwall might be more gentle on.

By using it as a powerwall, you woud indeed put 'miles' on the EV battery and it's not negligible by far.

But I do see the benefit for supplemental use during emergencies. That's a good thing! It wouldn't be too difficult to have the charger back feed 240V back into the system just like a Tesla Powerwall would do.
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