Bloemfontein upcoming install

[JoeSlow]

15 minutes ago, PowerUser said:

@JoeSlow is running crypto miners still so profitable to pay for this whole system? 

Well yes in my case. I wanted a solar system since we bought the house. The friend who is a pilot in Port Alfred decided to go the crypto mining route and asked if I'd manage everything for him in Bloemfontein since he isn't interested on how it works, it just needs to make $. The past 5 days has cost us around R1000 - R1500 due to load shedding. 

So he's buying Eskom power at R2.5 a unit from me currently which will continue except all the power the Solar makes I will get and not Eskom. So indirectly I'm "selling kws to him albeit in a very legal way" which ends with him paying for my Solar system if the market go's on for long enough, could be up to 50% of the systems cost in under 2 years. The big ifs will come when Ethereum goes to POS from POW. 

Edited November 12, 2021 by JoeSlow

[JoeSlow]

11 minutes ago, Nexuss said:

If you are going for a really large battery bank i would suggest you look into using LiFePo4 batteries for extra longevity . Hubble AM2 uses a chemistry more suited to people running only one or 2 batteries(higher energy density /higher discharge and charge rates ) but shorter lifespan. 

I saw this during my research but liked the form factor and price of the battery. Will definitely think about LiFePo4 in future. Thanks for the input.

[Buyeye]

11 minutes ago, JoeSlow said:

I saw this during my research but liked the form factor and price of the battery. Will definitely think about LiFePo4 in future. Thanks for the input.

I think it's a rebranded pylontech or dyness not sure but it is Lithium iron phosphate. 

[PowerUser]

10 minutes ago, Buyeye said:

I think it's a rebranded pylontech or dyness not sure but it is Lithium iron phosphate. 

Looks like, it's 0.5C battery and it's not on the SunSynk compatibility list. Not sure if CAN communication will work with the inverter.

[Buyeye]

2 minutes ago, PowerUser said:

Looks like, it's 0.5C battery and it's not on the SunSynk compatibility list. Not sure if CAN communication will work with the inverter.

It would be fine since he is starting with 2. 2 would match the inverter requirements perfectly. Not sure about bms but it's a relatively new battery newer than my powerbox so bms should work.

I just checked it's a rebranded dyness.

[JoeSlow]

2 minutes ago, Buyeye said:

It would be fine since he is starting with 2. 2 would match the inverter requirements perfectly. Not sure about bms but it's a relatively new battery newer than my powerbox so bms should work.

I just checked it's a rebranded dyness.

Thanks for the info so it should be compatible 100%.

I'm guessing when it comes to batteries one cannot mix different batteries? Or can you connect additional batteries to inverter but charge them from a separate MPPT? I've seen a few posts here where guys have to sell their batteries cause they cannot upgrade due to the batteries end of life for production. This is a major concern for me cause it means I won't be able to get the same battery to upgrade my capacity in say 2 years from now cause it might be discontinued.

Or am i missing something with regards to different batteries supplying a single inverter? Plan was also to go for a 2nd 5kw Sunsynk if ever needed so guess I can add another different brand of batteries there in future?

[PowerUser]

6 minutes ago, Buyeye said:

It would be fine since he is starting with 2. 2 would match the inverter requirements perfectly. Not sure about bms but it's a relatively new battery newer than my powerbox so bms should work.

I just checked it's a rebranded dyness.

It's 23k for 4.8kWh vs 24k for 5.5kWh for the Hubble. So, it's not cheaper. Isn't Dyness a rebranded Pylontec?

[Buyeye]

4 minutes ago, PowerUser said:

It's 23k for 4.8kWh vs 24k for 5.5kWh for the Hubble. So, it's not cheaper. Isn't Dyness a rebranded Pylontec?

I was only finding him a similar form factor lifepo4 battery. Because of the advantages of lifepo4 mentioned on an earlier post.

[PowerUser]

6 minutes ago, Buyeye said:

I was only finding him a similar form factor lifepo4 battery. Because of the advantages of lifepo4 mentioned on an earlier post.

I'm yet to be convinced of any advantages of LiFePO4 vs the LiNMC cells in the Hubbles. Still haven't seen enough information to convince me either way. However, on paper, the LiNMC cells in the Hubble seems to pack more energy for higher loads.

Edited November 12, 2021 by PowerUser

[JoeSlow]

4 minutes ago, PowerUser said:

I'm yet to be convinced of any advantages of LiFePO4 vs the LiNMC cells in the Hubbles. Still haven't seen enough information to convince me either way. However, on paper, the LiNMC cells in the Hubble seems to pack more energy for higher loads.

The true 1C rating was another reason going for the Hubble. If there is extra PV capacity the battery can be charged at twice the speed of a .5C battery. So could potentially cycle the battery an additional or half time each day which can help with lower grid usage and not wasting PV output when demand is not from appliances. So battery could handle the otherwise grid loads. 

Haha I'm getting all the more confused of how to make use of all the available power and not let any go to waste. Water heating seems to be one of the places one can direct additional power. Swimming pool pump also something to run at day peak production.

[Nexuss]

3 minutes ago, PowerUser said:

I'm yet to be convinced of any advantages of LiFePO4 vs the LiNMC cells in the Hubbles. Still haven't seen enough information to convince me either way. However, on paper, the LiNMC cells in the Hubble seems to pack more energy for higher loads.

Lets do some simple calculations : AM2 vs UP5000

5.5kwhx 3000 cycles =16500kwh that you can run through the battery before you hit 80% capacity left.

4.8kwh x4500 cycles=21600kwh  before 80% capacity left .

21600-16500= 5100kwh you are missing out on .

5100x R2,40 avg price per kwh and that is over R12k worth of electricity.

AM2 vs US 3000C

5.5kwhx 3000 cycles =16500kwh

3.5kwh x 6000cycles=21000kwh 

4500kwh you are missing out on. 

 

 

[JoeSlow]

Haha you guys are going to give me buyers remorse! 

[PowerUser]

28 minutes ago, Nexuss said:

Lets do some simple calculations : AM2 vs UP5000

5.5kwhx 3000 cycles =16500kwh that you can run through the battery before you hit 80% capacity left.

4.8kwh x4500 cycles=21600kwh  before 80% capacity left .

21600-16500= 5100kwh you are missing out on .

5100x R2,40 avg price per kwh and that is over R12k worth of electricity.

AM2 vs US 3000C

5.5kwhx 3000 cycles =16500kwh

3.5kwh x 6000cycles=21000kwh 

4500kwh you are missing out on. 

 

 

You cannot compare like that! It’s very wrong!

The 3000 cycles for AM-2 are based on 1C 100% DOD at 35 deg Celsius temp. I’m yet to see lifecycles at 80% DOD for the Hubble at 0.5C and lower temperature. Then you can compare to your LiFePO4 stats. 

Edited November 12, 2021 by PowerUser

[JoeSlow]

@Nexuss & @PowerUser

Hey guys:

 

[Nexuss]

48 minutes ago, PowerUser said:

You cannot compare like that! It’s very wrong!

The 3000 cycles for AM-2 are based on 1C 100% DOD at 35 deg Celsius temp. I’m yet to see lifecycles at 80% DOD for the Hubble at 0.5C and lower temperature. Then you can compare to your LiFePO4 stats. 

See Figure 2b. 80% DOD @ 0,5C

https://iopscience.iop.org/article/10.1149/1945-7111/abae37/pdf

NMC cells actually do better with hotter temperatures btw.  

[PowerUser]

10 minutes ago, Nexuss said:

See Figure 2b. 80% DOD @ 0,5C

https://iopscience.iop.org/article/10.1149/1945-7111/abae37/pdf

NMC cells actually do better with hotter temperatures btw.  

This paper has no relevance to the particular NMC cells used in the Hubble. I can also Google... But that still doesn't prove anything.

 

 

 

[Buyeye]

LiNMC is truly impressive.

You must remember some of us come from lead acid that would die at the thought of 100% depth of discharge. Most people need 10kwh to 40kw to meet our needs so this is a huge investment. You can think of it as classical conditioning in psychology terms. We lost batteries in prolonged power outages so we are a bit averse to that type of situation/risk.

We are more inclined to believe that  0,5C will treat our batteries better.

The 10 year warranties with large number of cycles gives us hope that the batteries will actually last 10 years and more.

[Guest Sarel]

A basic list of batteries to compare. If you want something on there, let me know and I can add that.

[Nexuss]

11 minutes ago, PowerUser said:

This paper has no relevance to the particular NMC cells used in the Hubble. I can also Google... But that still doesn't prove anything.

 

haha can you elaborate on why you think the hubble's NMC cells are superior to other NMC cells?  

12 minutes ago, Buyeye said:

LiNMC is truly impressive.

I agree . If you look at the study i posted the figures for NMC cells between 20-80% SOC and 40-60% SOC are really impressive and just shows why they have been so good in EV's. For home solar storage we typically do not stay between 20-80% SOC though. You want to cycle as much of the battery possible everyday to utilize it the most and make it pay for itself quicker. So we have to look at the 100% DOD stats. That being said LFP cells are improving(higher charge and discharge rates) and are starting to become used in the EV market to a large degree . Tesla switched to LFP cells for all its standard range cars . “LFP has both positive and negative trade-offs,” said Sam Abuelsamid, Guidehouse Insights principal analyst. “It’s significantly cheaper and doesn’t require any nickel or cobalt. It’s also more stable, which makes it safer.”

 

[PowerUser]

2 hours ago, Nexuss said:

haha can you elaborate on why you think the hubble's NMC cells are superior to other NMC cells?  

 

Haha, if you look at that paper properly, you will see that on diagram 3em the study claims, that at 100% DOD and 0.5C discharge rate, the NMC cells will diminish their capacity to 80% of the initial capacity in less than 500 cycles (the highlighted red line):

 

On the other hand Hubble claims, that at 100% DOD and 1C discharge rate, their NMC cells will diminish their capacity to 80% of the initial capacity in around 3000 cycles!

That leads to the conclusion, either Hubble grossly exaggerates (6 times), the longevity of their cells (which everyone should've noticed already), or the NMC cells used in that study and completely different and much inferior to the NMC cells used in the Hubble batteries. What do you think?

Please note, I have no connection with Hubble at all, besides that I purchased one of their batteries for my system. So, I'm not biased at all.

And please, when you Google and look at numbers, try also to understand what is going on in the background of those studies and numbers!

[Nexuss]

14 minutes ago, PowerUser said:

That leads to the conclusion, either Hubble grossly exaggerates (6 times), the longevity of their cells (which everyone should've noticed already), or the NMC cells used in that study and completely different and much inferior to the NMC cells used in the Hubble batteries. What do you think?

Honestly i dont know what to think but i wouldnt personally take that gamble. 

I dont think there is anybody doing 0-100% cycles everyday on their AM2 so it would maybe not be noticed as quick as you would think ... on 80% DOD the cycles go up by lots, so its still many many years of service. 

19 minutes ago, PowerUser said:

Please note, I have no connection with Hubble at all, besides that I purchased one of their batteries for my system. So, I'm not biased at all.

well the fact that you have one kinda makes you biased then IMO lol . To that i would add i have nothing at all against Hubble as a company , i just got a friend to buy their S100 battery actually.

[PowerUser]

26 minutes ago, Nexuss said:

Honestly i dont know what to think but i wouldnt personally take that gamble. 

I dont think there is anybody doing 0-100% cycles everyday on their AM2 so it would maybe not be noticed as quick as you would think ... on 80% DOD the cycles go up by lots, so its still many many years of service. 

 

Ok, let's leave the 0-100% if they make you uncomfortable. I'm not sure where you got your numbers for 80% DOD and how close they are to anything, not to be noticed.... I'm yet to see 80% DOD curve for the Hubbles. Please share it, if you have it.

Unless I'm going blind, the black line represents from 20% to 80% charge, which would give 60% DOD. That is much more closer to the Hubble 50% DOD stats. On the above diagram 60% DOD is somewhere between 1500 to 2000 cycles to reach 80% initial capacity. Hubble NMC claim 6000 cycles at 50 % DOD to reach 80% initial capacity. The difference again is 3 to 4 times! That is substantial difference and again, not something small and unnoticeable!

Please.... if your school math teacher is still teaching somewhere.... tell that person to either retire or take up another job away from numbers.... 

[PowerUser]

1 minute ago, 87 Dream said:

Pop corn time 

Nope, we finished the popcorn already. You missed the party…  

[PowerUser]

15 minutes ago, 87 Dream said:

In all honesty, time will tell with NMC, all I can add to the valid points already mentioned:

I could never install anything in a client's home that is a risk of the type that NMC offers. Forget Google have a look at a hammer test of an NMC cell. Look into deeper reasons why a billion dollar company like Tesla changed Chemistry. It has nothing to do with some of the things mentioned here. They don't make decisions willy nilly.

Look at the liability to a billion dollar company should a Tesla end up in a very high energy crash in the US. I trust LFP, because it's safe!! Tesla started to find that they had a huge problem with containment of the battery enclosure box. They needed to strengthen so many things to contain the battery pack. They needed a vacuum, because you cannot contain a fire of that nature.

There is a reason the cells of NMC can deliver high C ratings. They are extremely volatile.  It's another Boeing 787 big corporate company type of thing. However, in the Aviation game, you can spend millions to type certify changes to a design. Hence Boeing did not change supplier nor the design, they just built a very very thick stainless steel box that can vent & contain the fire for long enough. I hope your Hubble is installed securely because if it drops & has a hard landing brace yourself...It's not my opinion it's facts. I fly with LFP on board my aircraft to places where we are 240mins away from a landing airport over the North pole. It is safe enough for this. They are not classified as the same. Forget cycles & whatever. Think safety!!!

87

https://youtu.be/Bg_480HUheo

 

If all other arguments fail... time to play the scary game... typical!

[Leshen]

I think what you guys fail to understand about the Hubble AM2 is that the cells are rated at 2.5C. Thats 250A at 50V. So do you really think that 100A will be a heating issue for this battery?