GRA
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Re: Autonomous Vehicles, LEAF and others...

Tue Feb 06, 2018 7:46 pm

Via GCC:
Hyundai NEXO fuel-cell vehicles self-drive (Level 4) 118 miles from Seoul to Pyeongchang
http://www.greencarcongress.com/2018/02/20180204-nexo.html

. . . Five Hyundai vehicles completed the journey. Three vehicles are based on Hyundai’s next-generation fuel cell electric SUV NEXO, scheduled to be released in Korea next month, and the other two are Genesis G80 autonomous vehicles. All vehicles are equipped with level 4 self-driving technology, as defined by the SAE international standards, and 5G network technology. . . .

The Hyundai test marks the first time autonomous vehicles have operated on public highways at 110 km/h (68 mph), the maximum speed allowed by law on Korean highways.

The demonstration took place in Seoul on 2 Feb, with the ‘CRUISE’ and ‘SET’ buttons being pressed on the autonomous-driving steering wheel of each vehicle, at which point the cars immediately switched to self-driving mode and began the 118-mile journey to Pyeongchang.

Entering the highway, the vehicles moved in response to the natural flow of traffic, executed lane changes, overtaking maneuvers and navigated toll gates using Hi-pass, South-Korea’s wireless expressway payment system. . . .

During autonomous driving, a high volume of data is processed by the vehicles on board systems, necessitating large power consumption. A fuel cell electric vehicle is able to produce electricity to meet this power consumption, as well as powering the vehicles drive systems. Hyundai says that the fuel cell vehicle is optimal for this type of test. . . .

As mentioned upthread, I've been increasingly seeing the power requirements of autonomy being a possibly significant obstacle to combining them with BEVs. Presumably power needs will decrease over time, so we'll see if that happens in time to avoid this issue.
Guy [I have lots of experience designing/selling off-grid AE systems, some using EVs but don't own one. Local trips are by foot, bike and/or rapid transit].

The 'best' is the enemy of 'good enough'. Copper shot, not Silver bullets.

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RegGuheert
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Re: Autonomous Vehicles, LEAF and others...

Wed Feb 07, 2018 1:10 am

GRA wrote:As mentioned upthread, I've been increasingly seeing the power requirements of autonomy being a possibly significant obstacle to combining them with BEVs.
You must be joking. The power capabilities of BEVs are significantly higher than that of H2 FCVs.

Likely you are talking about the impact of the energy consumption of the electronics on range. I find it interesting that you are still coming here in 2018 bellyachng about this. Today, we have the following BEVs available for sale in the market:

- Tesla offers three different cars with over 300 miles of EPA range.
- GM offers a car with over 200 miles of EPA range.
- Nissan offers the LEAF with 150 miles of EPA range.
- Proterra makes a BEV city bus with a 660-kWh battery that has demonstrated the ability to drive 1100 miles on a single charge in ideal conditions. That bus should be able to easily travel over 300 miles in even very challenging conditions.

We also have the following BEVs being prepared for sale in the marketplace soon:

- Tesla is developing two Class 8 Semi trucks, one with nearly 1 MWh of energy storage and 500 miles of range claimed.
- Tesla has announce a new version of the Roadster which should have over 600 miles of EPA range.

Seriously, let it go. The days of BEVs being limited to 60 miles of energy storage are quickly moving into history. And they do it without wasting over half of the energy provided to them.
GRA wrote:Presumably power needs will decrease over time, so we'll see if that happens in time to avoid this issue.
What issue? Of course computing power requirements decrease with time. That's a given. And I posted about massive improvements to the cost (and I will assume also the power consumption) of LiDAR in the post immediately preceding yours.

When you see that something consumes a lot of electrical energy, you would be much better off worrying about how that energy will be efficiently sourced with a minimum of impact to the environment. H2 FCVs do it with the MOST impact of all the options available today. BEVs do it with the least impact and they are improving very rapidly.

In any case, as long as autonomy consumes massive amounts of power, that means it is extremely expensive and will either remain in the lab or will be confined to very few niche applications. it will need to be productized before it will see widespread application.

I do find it interesting that Hyundai is already demonstrating Level 4 Autonomy. Let's not get confused because Hyundai points out a corner case where H2 FCVs have a very slight, temporary advantage over BEVs in one insignificant, also temporary area and entirely lose sight of the massive drawbacks that technology brings to the table.
RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

cwerdna
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Re: Autonomous Vehicles, LEAF and others...

Wed Feb 07, 2018 1:18 am

A self-driving truck just drove from Los Angeles to Jacksonville:
https://www.cnbc.com/2018/02/06/embark- ... ville.html

The company involved is Embark, which I'd not heard of, until now.

'13 Leaf SV w/premium package (owned)
'13 Leaf SV w/QC + LED & premium packages (lease over, car returned)
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Please don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

GRA
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Re: Autonomous Vehicles, LEAF and others...

Wed Feb 07, 2018 8:36 pm

RegGuheert wrote:
GRA wrote:As mentioned upthread, I've been increasingly seeing the power requirements of autonomy being a possibly significant obstacle to combining them with BEVs.
You must be joking. The power capabilities of BEVs are significantly higher than that of H2 FCVs.

RegGuheert wrote:Likely you are talking about the impact of the energy consumption of the electronics on range.
Yup. Should have written energy.

I find it interesting that you are still coming here in 2018 bellyachng about this.

Uh, still? I hadn't even considered it as an issue until I read "Driverless: Intelligent Cars and the Road Ahead" last year, and then started to see it mentioned more and more with respect to BEVs, with some calcs showing the effects on range. I have no opinion either way, as I don't know enough about the current state of the art.

RegGuheert wrote:Today, we have the following BEVs available for sale in the market:

- Tesla offers three different cars with over 300 miles of EPA range.
- GM offers a car with over 200 miles of EPA range.
- Nissan offers the LEAF with 150 miles of EPA range.
- Proterra makes a BEV city bus with a 660-kWh battery that has demonstrated the ability to drive 1100 miles on a single charge in ideal conditions. That bus should be able to easily travel over 300 miles in even very challenging conditions.

We also have the following BEVs being prepared for sale in the marketplace soon:

- Tesla is developing two Class 8 Semi trucks, one with nearly 1 MWh of energy storage and 500 miles of range claimed.
- Tesla has announce a new version of the Roadster which should have over 600 miles of EPA range.

Seriously, let it go. The days of BEVs being limited to 60 miles of energy storage are quickly moving into history. And they do it without wasting over half of the energy provided to them.

No one's talking about 60 mile BEVs, they're talking about longer range BEVs (and other cars), using significant amounts of battery energy to run the sensors and computers. If BEVs need to use a large proportion of their electrical energy to run the autonomous systems, they are obviously the tech whose range will be most affected. Whether or not that range reduction will be judged serious or not by consumers and companies remains to be seen.

RegGuheert wrote:
GRA wrote:Presumably power needs will decrease over time, so we'll see if that happens in time to avoid this issue.
What issue? Of course computing power requirements decrease with time. That's a given. And I posted about massive improvements to the cost (and I will assume also the power consumption) of LiDAR in the post immediately preceding yours.
And the hope is that all the other sensors will also decrease, so that this will prove a minor issue. We aren't there yet, so we don't know how the timing will go.

RegGuheert wrote:When you see that something consumes a lot of electrical energy, you would be much better off worrying about how that energy will be efficiently sourced with a minimum of impact to the environment. H2 FCVs do it with the MOST impact of all the options available today. BEVs do it with the least impact and they are improving very rapidly.

In any case, as long as autonomy consumes massive amounts of power, that means it is extremely expensive and will either remain in the lab or will be confined to very few niche applications. it will need to be productized before it will see widespread application.
Right, so the question is will the timing of autonomy and energy reduction be out of sync or not?

RegGuheert wrote:I do find it interesting that Hyundai is already demonstrating Level 4 Autonomy. Let's not get confused because Hyundai points out a corner case where H2 FCVs have a very slight, temporary advantage over BEVs in one insignificant, also temporary area and entirely lose sight of the massive drawbacks that technology brings to the table.

As is usually the case with consumer products, the public will decide which benefits and disadvantages are most important to them. I have no idea which will succeed, and whether or not this will prove a significant handicap for autonomous BEVs (or FCEVs FTM) compared to ICEs. But I posted the info here because of the L4, not because it was an FCEV.
Guy [I have lots of experience designing/selling off-grid AE systems, some using EVs but don't own one. Local trips are by foot, bike and/or rapid transit].

The 'best' is the enemy of 'good enough'. Copper shot, not Silver bullets.

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RegGuheert
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Re: Autonomous Vehicles, LEAF and others...

Thu Feb 08, 2018 3:11 am

GRA wrote:But I posted the info here because of the L4, not because it was an FCEV.
You could've fooled me, since the only thing you commented on was how you had to have a fuel cell to do that drive and said NOTHING about the Level 4 capability. And you continue on, as if the issue is a big one.

All Teslas and the 2018 Nissan LEAF have autonomous features availavable for sale TODAY. I wonder how they manage to power all the sensors that they include. GM is targeting the using the Chevy Bolt for all their autonomous vehicle work. To my knowledge, NO H2 FCV available today has these features.

Yes, the sensors in autonous vehicles can and are powered by production BEVs. No, these features are not available in H2 FCVs today.
RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

GRA
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Re: Autonomous Vehicles, LEAF and others...

Thu Feb 08, 2018 6:48 pm

RegGuheert wrote:
GRA wrote:But I posted the info here because of the L4, not because it was an FCEV.
You could've fooled me, since the only thing you commented on was how you had to have a fuel cell to do that drive and said NOTHING about the Level 4 capability. And you continue on, as if the issue is a big one.

I t seems I did fool you. I went back and forth for a while about whether to post it in this topic, the Nexo one or cross-post in both, but ultimately decided that the type of propulsion was less important than the claim of L4 capability, as they put it in both the FCEV and the other vehicles.

RegGuheert wrote:All Teslas and the 2018 Nissan LEAF have autonomous features availavable for sale TODAY. I wonder how they manage to power all the sensors that they include. GM is targeting the using the Chevy Bolt for all their autonomous vehicle work. To my knowledge, NO H2 FCV available today has these features.

Yes, the sensors in autonomous vehicles can and are powered by production BEVs. No, these features are not available in H2 FCVs today.

As none of the Teslas, Nissans or Chevys you mention are currently available with autonomy (which is defined by the SAE as L4 or L5) yet, nor is any other vehicle that can be sold to the public and used on a public road without a safety monitor present, I don't agree with your statement. Quite frankly, until I read some of the concerns and details of the energy requirements for full autonomy in "Driverless", it'd never even occurred to me that there might be an issue. I lack the knowledge to say if it will be one when the time comes, but people who know far more about the subject than I do have been bringing it up so I feel it deserves to be mentioned, and have posted links to such. "Driverless" described it as a potential problem (among several others), one which might need to be solved to allow autonomous BEVs to achieve their goals, but the book is about autonomy, not AFVs.
Guy [I have lots of experience designing/selling off-grid AE systems, some using EVs but don't own one. Local trips are by foot, bike and/or rapid transit].

The 'best' is the enemy of 'good enough'. Copper shot, not Silver bullets.

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RegGuheert
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Re: Autonomous Vehicles, LEAF and others...

Fri Feb 09, 2018 4:06 am

Here's a recent article that supports your assertion, GRA:
AutoWeek wrote:How much power are we talking about?

Bloomberg says that current prototypes for fully autonomous driving systems consume the equivalent energy of 50 to 100 laptops, citing supplier BorgWarner. This translates to 2 to 4 kilowatts of electricity, which in a modern car makes it 5 to 10 percent more difficult to meet fuel economy and carbon emission targets.
Simply put, that IS a lot of power.

So lets run the numbers and find out whether the assertion that this will keep fully-autonomous BEVs off the road for the near future is a credible one.

First of all, a 4 kW load connected to the 12-V power in a car would draw OVER 300 A of current (assuming a float voltage of about 13 V like we see in the LEAF). I am unaware of ANY vehicle with this much current available at 12 V. That's over twice the current that the DC-DC converter in my 2011 LEAF can put out. Even the local rednecks who "amp up" the electrical systems in their pickup trucks so that they can operate the hydraulics for a snowplow are limited to about 300 A TOTAL.

That explains why these developments are being done almost exclusively on vehicles with electric drivetrains, since those have 10s or 100s of kW of electrical power available from the traction battery.

Even though that power level is for prototypes and such a power-hungry system would NEVER be put into a production car, let's just run the numbers anyway to see what it really would mean for the range of a modern BEV. I will define a 10% hit on range as the limit of what is reasonable. I will also use a 2018 Chevy Bolt as the reference vehicle, as it is what GM is targeting for fully-autonomous operation in 2019. The Bolt has over 60 kWh available but for this calculation, let's use 60 kWh.

10% of 60 kWh is 6 kWh. In other words, you could take advantage of autonomy for 1.5 hours at 4 kW or 3 hours at 2 kW and still have 90% of your range left. Put another way, the range mentioned in the article could easily be met by the Chevy Bolt equipped with an autonomy system that draws 2 kW, but with a 4-kW system it would exceed the 10% limit I set (but likely would still be able to make the drive).

But no automaker would field an autonomous system which draws more power than the resistive heater in my LEAF consumes in 10 F temperatures. That's the difference between a prototype and a product. So, how much power WILL the first fully-autonomous systems draw. I will put the ABSOLUTE upper limit at 1 kW, but I seriously doubt any automaker would ever commit to a system that consumed more than 500 W. Why? Because there are far too many knock-on effects to try to add another kW load into the car. But let's look at the effect of a 1-kW autonomy system on various vehicles' range.

Here are the number of hours that could be driven using a 1-kW autonomy system before 10% of the battery capacity is consumed:

- 2018 Chevy Bolt (60 kWh): 6 hours
- 2018 Nissan LEAF (36 kWh): 3.6 hours
- 2018 Tesla Model 3 (75 kWh): 7.5 hours
- 2018 Tesla Model X P100D (100 kWh): 10 hours
- 2018 Proterra Catalyst E2 max (660 kWh): 66 hours
- 2019 Nissan LEAF (55 kWh): 5.5 hours
- 2019 Tesla Truck (900 kWh): 90 hours
- 2020 Tesla Roadster 2 (200 kWh): 20 hours

Sorry, GRA, but this is not an issue for actual BEVs. Let's not imagine that autonomy is some sort of justification to field H2 FCVs. It is not.
RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

GRA
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Re: Autonomous Vehicles, LEAF and others...

Sat Feb 10, 2018 1:21 pm

First off, let me apologize for stating that I first read about this issue in "Driverless". I thought I had, but re-read the book last night and it wasn't mentioned there, so it must have been somewhere else; sorry for the bad steer. I'm pretty sure I posted two or three links referencing this issue on MNL, either upthread or elsewhere, and will try to find them.

"Driverless" is still well worth the read to anyone interested in AVs, as it discusses the history, technical (AI, sensors), regulatory, legal (who's at fault), societal (jobs, housing) and ethical (the Trolley problem) issues involved in bringing this tech to market, and potential positive and negative effects from same. One of the authors was part of the team from Carnegie Mellon Univ. that took part in the DARPA challenges, and the notes almost all have URLs to the papers etc. cited, so it's a great source of further info. The info on how AI has developed and the difference between symbolic (rules-based) and machine learning AI (esp. deep learning) approaches is particularly useful to anyone who, like me, is unfamiliar with this stuff.

RegGuheert wrote:Here's a recent article that supports your assertion, GRA:
AutoWeek wrote:How much power are we talking about?

Bloomberg says that current prototypes for fully autonomous driving systems consume the equivalent energy of 50 to 100 laptops, citing supplier BorgWarner. This translates to 2 to 4 kilowatts of electricity, which in a modern car makes it 5 to 10 percent more difficult to meet fuel economy and carbon emission targets.
Simply put, that IS a lot of power.

So lets run the numbers and find out whether the assertion that this will keep fully-autonomous BEVs off the road for the near future is a credible one.

First of all, a 4 kW load connected to the 12-V power in a car would draw OVER 300 A of current (assuming a float voltage of about 13 V like we see in the LEAF). I am unaware of ANY vehicle with this much current available at 12 V. That's over twice the current that the DC-DC converter in my 2011 LEAF can put out. Even the local rednecks who "amp up" the electrical systems in their pickup trucks so that they can operate the hydraulics for a snowplow are limited to about 300 A TOTAL.

That explains why these developments are being done almost exclusively on vehicles with electric drivetrains, since those have 10s or 100s of kW of electrical power available from the traction battery.

Even though that power level is for prototypes and such a power-hungry system would NEVER be put into a production car, let's just run the numbers anyway to see what it really would mean for the range of a modern BEV. I will define a 10% hit on range as the limit of what is reasonable. I will also use a 2018 Chevy Bolt as the reference vehicle, as it is what GM is targeting for fully-autonomous operation in 2019. The Bolt has over 60 kWh available but for this calculation, let's use 60 kWh.

10% of 60 kWh is 6 kWh. In other words, you could take advantage of autonomy for 1.5 hours at 4 kW or 3 hours at 2 kW and still have 90% of your range left. Put another way, the range mentioned in the article could easily be met by the Chevy Bolt equipped with an autonomy system that draws 2 kW, but with a 4-kW system it would exceed the 10% limit I set (but likely would still be able to make the drive).

But no automaker would field an autonomous system which draws more power than the resistive heater in my LEAF consumes in 10 F temperatures. That's the difference between a prototype and a product. So, how much power WILL the first fully-autonomous systems draw. I will put the ABSOLUTE upper limit at 1 kW, but I seriously doubt any automaker would ever commit to a system that consumed more than 500 W. Why? Because there are far too many knock-on effects to try to add another kW load into the car. But let's look at the effect of a 1-kW autonomy system on various vehicles' range.

Here are the number of hours that could be driven using a 1-kW autonomy system before 10% of the battery capacity is consumed:

- 2018 Chevy Bolt (60 kWh): 6 hours
- 2018 Nissan LEAF (36 kWh): 3.6 hours
- 2018 Tesla Model 3 (75 kWh): 7.5 hours
- 2018 Tesla Model X P100D (100 kWh): 10 hours
- 2018 Proterra Catalyst E2 max (660 kWh): 66 hours
- 2019 Nissan LEAF (55 kWh): 5.5 hours
- 2019 Tesla Truck (900 kWh): 90 hours
- 2020 Tesla Roadster 2 (200 kWh): 20 hours

Sorry, GRA, but this is not an issue for actual BEVs. Let's not imagine that autonomy is some sort of justification to field H2 FCVs. It is not.

Thanks for the above, and BTW, it's not my assertion, it's the assertion of articles like that one and the experts they've consulted. As to it being some sort of justification for FCEVs, that remains to be seen. I've mentioned that it might be an issue that could noticeably reduce the range of any AV based on a BEV, which might make the vehicle less acceptable to consumers, and thus shift interest in ZEV AVs to FCEVs. It does look like short-range, low cost privately-owned urban BEVs would be most impacted, especially when the knock-on effects are added (extra weight of the computers, sensors and data storage etc. with the necessary redundancy, structural weight to carry it and any motor power increases to maintain performance), but as long as battery costs come down soon enough it may not matter.

As to how much juice prototypes are using, one of the things that "Driverless" makes clear is the enormous change from L3 or below to L4 and above in terms of computational and sensor power and data storage. These are improving rapidly (companies like Nvidia who make computer game processors leading the way), so the problem may be solved before it becomes an issue. All the recent articles I could find with a Google seem to cite or are at least based on the info in that same Bloomberg article, but arrive at slightly different conclusions. Here's C&D's: https://blog.caranddriver.com/self-driving-vehicles-may-save-energy-despite-power-hog-tech-on-board/

Here's a more recent (4 days ago) article from Wired: https://www.wired.com/story/self-driving-cars-power-consumption-nvidia-chip/

Here's a GCC article:
Continental and NVIDIA partnering on autonomous vehicle systems; market introduction in 2021
http://www.greencarcongress.com/2018/02/20180206-conti.html

NVIDIA and Continental are partnering to create AI (artificial intelligence) self-driving vehicle systems built on the NVIDIA DRIVE platform, with a planned market introduction starting in 2021 for Level 3 functionality. . . .

So, I'd say I'm now leaning cautiously optimistic that it won't be a major issue by the time L4 AVs are actually for sale to the public, but it bears watching.
Guy [I have lots of experience designing/selling off-grid AE systems, some using EVs but don't own one. Local trips are by foot, bike and/or rapid transit].

The 'best' is the enemy of 'good enough'. Copper shot, not Silver bullets.

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RegGuheert
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Re: Autonomous Vehicles, LEAF and others...

Sat Feb 10, 2018 6:47 pm

GRA wrote:Here's a more recent (4 days ago) article from Wired: https://www.wired.com/story/self-driving-cars-power-consumption-nvidia-chip/
Thanks. Good article.

In the processing world, you can nearly always trade hardware against speed and power issues. But new chip designs do not come cheap, so this is typically only done for specific applications if the addressable market is extremely large. This is just that sort of market.

Eventually these systems will drop well below 100W.
RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

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RegGuheert
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Re: Autonomous Vehicles, LEAF and others...

Sun Feb 11, 2018 5:19 am

Looking at this further, the Xavier AI supercomputer looks a lot like the follow-on to the Tegra X1 processor that Tesla uses in their cars. Here are the main differences:

1) Move from 20 nm to 16 nm process.
2) 512-core Volta GPU rather than 256-core Maxwell GPU
3) 8-core CPU versus 4-core CPU
4) 8K versus 4K video processor

What appears to be new are the "computer vision accelerator" and the "deep learning accelerator".

Here is an excellent primer on what "deep learning" actually is and what it means:

RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

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