Depth of Discharge under load

[SunEagle]

You are a freaking genius, of course it would have been much cheaper for me to move my family overseas to get cheaper electricity rather than install battery/solar..

That about sums up your level of advice!

Actually SK is back in Oklahoma but then again your ability to move to find a lower cost power is probably not a good idea.

What I don't understand is why people have to justify the purchase of batteries because they pay so much for power from their POCO. It would be less costly if someone with high electric rates to just reduce their usage instead of buying something that does not last a long time to "solve the problem". Conservation is still the cheapest way to save money by reducing your electrical footprint.

[tom rickard]

Snowflake you are a moron. I pay 8-cents per Kwh. You believe in nonsense. That is what they tech in schools to Snowflakes and Millennials. The world is not a nice place, grow some balls and deal with it. .

You are a freaking genius, of course it would have been much cheaper for me to move my family overseas to get cheaper electricity rather than install battery/solar..

That about sums up your level of advice!

[Sunking]

Where i live, electricity costs around 45c/kwh.

Snowflake you are a moron. I pay 8-cents per Kwh. You believe in nonsense. That is what they tech in schools to Snowflakes and Millennials. The world is not a nice place, grow some balls and deal with it. .

[Ampster]

So, what's the sense in asking ?

It was a rhetorical question with an alluson. If you didnt get it, not worth my time explaining.

[Bala]

Bala. Thankyou for perfectly illustrating my point. 12 years ago the options for off-grid were poor, and the systems weren't as capable as they are now. Times have changed.

Assuming all components will fail at the end of their warranty period, it will still be cheaper for me to have off-grid power than connect to grid. This is an example of a professionally installed system capable of delivering 20kwh daily.

System components:
SMA Sunny Island 8.0
SMA SunnyBoy SB 5.0
BYD BBox (8 units) 20kwh
5kw panels
Auto Start genset (your choice, approx $5k)

Fully installed for $30k, warranty on all components except genset is 10 years, all components are changeover under warranty.

In Australia there have been thousands of this type of system installed, the technology has been verified over the last decade..

I feel you are not including all factors in your costing.

Byd warranty is 10 years, but only for 60% capacity, or a set amount of through out.

sunny island 5 years or you can buy more.

generator running expenses??? Who is going to service and maintain it. $100 an hrs in Australia if you can get someone to come out.

then you have the problem of actually claiming warranty. Each vendor simply blames the other. Or they did some little thing to good warranty.

There is also capital outlay consideration.

I feel a blanket statement saying stand alone is a direct replacement cost wise to grid is misleading.

It has its place for sure but only when all the facts are on the tablet

[SunEagle]

There is a subtle difference between off grid and self consumption (Aso sometimes referred to as Net Zero). The latter uses the grid for redundancy and therefore the extra layer and cost of a generator isn't there. I use the term Net Zero loosely because some would argue to be truly Net Zero one would have to include transportation. While I have EVs and mostly charge at my home, I also travel by plane, ferry and charge away from the home with unknown sources of electricity.

And I agree that you have a better installation using grid tie with battery backup then just an off grid system.

I understand the concept of Net Zero and applaud the new codes to make a building more efficient. I am also willing to find any way I can reduce my electrical footprint provided it does not drastically change my current life style.

I have had way too many past incidents (industrial, commercial & home) when it comes to batteries and simple do not trust them to "be there" when I really need them. Along with the cost being so high (for now) I would rather invest in SNR technology.

We each have a reason to utilize solar. I am not one of those that feel we need to eliminate all forms of carbon producing electrical generation. I would rather have more reliable power which IMO comes in multiple forms and uses. So for now batteries, as a home energy storage system is just not on my radar.

[J.P.M.]

About a dozen people participated in this thread and it had almost 500 views. Does anyone know what the views are of those lurkers?

Assuming that lurkers are not members of this forum and so not allowed to post, there is no easy way to communicate with those folks.

So, I'd suggest the above question is moot, that is, a question asked in such a way as to be open to debate or discussion. But, since it seems lurkers' responses are necessary information to discuss your question, and since they cannot, or won't, by definition, respond, it seems you pose a moot question with no way to get a resolution.

The same question can be asked of any thread and any lukers. So, unless you ask in a rhetorical sense, with no way to get what seems to be necessary information ("Hey all you lurkers, what do you think ?" - how does that work ?) an answer or more information from those unable to answer is a dead end. So, what's the sense in asking ?

[Ampster]

But unless you get your batteries free or very cheap and decide to live a life style of near zero power consumption I have a hard time believing it is cheaper to be off grid then on.

There is a subtle difference between off grid and self consumption (Aso sometimes referred to as Net Zero). The latter uses the grid for redundancy and therefore the extra layer and cost of a generator isn't there. I use the term Net Zero loosely because some would argue to be truly Net Zero one would have to include transportation. While I have EVs and mostly charge at my home, I also travel by plane, ferry and charge away from the home with unknown sources of electricity.

[SunEagle]

California is the second most populous state and battery supported grid tied systems are selling quite well there. Yes there are subsidies on some of those systems. Tesla has no more SGIP money but people continue to buy Powerwalls. I apologize if that creates the allusion that other people are "bad people".
Tom has already stated that his power costs $0.45 per kWhr.
If this is such an important topic for you or J.P.M. why dont you create a separate topic? You might get a few more meaningful comments.

Maybe you are right in that a new topic needs to be created since the OP is now a Guest and probably long gone.

Don't apologize for any allusion you think you have created. There are a number of members that live either in CA, HI or New England that can "justify" using a battery along with their solar pv system and have stated and believe they are correct. But the reason is due to the very high electric rates in those areas.

I have always believed a grid tie system has an ROI and ends up being cheaper then purchasing all of your kWh from any POCO at any cost. The ROI just changes.

But unless you get your batteries free or very cheap and decide to live a life style of near zero power consumption I have a hard time believing it is cheaper to be off grid then on.

[Ampster]

Tom. It still depends on what you would be paying for electricity from your POCO. You may be getting cheaper power from you battery/solar system but I seriously doubt the majority of people in the US or elsewhere can make the same claim.

All I ask is that you temper your statement by at least stating where you live and what your POCO charges for a kWh.

California is the second most populous state and battery supported grid tied systems are selling quite well there. Yes there are subsidies on some of those systems. Tesla has no more SGIP money but people continue to buy Powerwalls. I apologize if that creates the allusion that other people are "bad people".
Tom has already stated that his power costs $0.45 per kWhr.
If this is such an important topic for you or J.P.M. why dont you create a separate topic? You might get a few more meaningful comments.

[SunEagle]

So in summary:

The original poster asked how to maximise the life of his batteries.

He was berated by a few others as being stupid, and a time waster for daring to ask that question.

A few statements were made that it was physically impossible for a battery to return more energy than was used in its creation.

This was refuted and backed up by anecdotal evidence as well as reference to scientific study.

When shown to be wrong, the perpetrators of the incorrect statements attempt to deflect by changing subject or playing victim.

Conclusion:
You can get cheaper power from battery/solar than from grid-connect, but for some unknown reason a few people will not like it..

Tom. It still depends on what you would be paying for electricity from your POCO. You may be getting cheaper power from you battery/solar system but I seriously doubt the majority of people in the US or elsewhere can make the same claim.

All I ask is that you temper your statement by at least stating where you live and what your POCO charges for a kWh.

[tom rickard]

Bala. Thankyou for perfectly illustrating my point. 12 years ago the options for off-grid were poor, and the systems weren't as capable as they are now. Times have changed.

Assuming all components will fail at the end of their warranty period, it will still be cheaper for me to have off-grid power than connect to grid. This is an example of a professionally installed system capable of delivering 20kwh daily.

System components:
SMA Sunny Island 8.0
SMA SunnyBoy SB 5.0
BYD BBox (8 units) 20kwh
5kw panels
Auto Start genset (your choice, approx $5k)

Fully installed for $30k, warranty on all components except genset is 10 years, all components are changeover under warranty.

In Australia there have been thousands of this type of system installed, the technology has been verified over the last decade..

[Bala]

Imo to simply compare price per kWh between what poco supply and what some off grinders ca get by on is not a true comparison.

if you price an off grid system that will supply minimum15kw continuously, professionally installed and maintained and factor in replacement costs of items once they are out of warranty then you will have a real price per kWh for the average person to compare.

yes some officers who are happy will a few kWh a day may do ok but not the general population.

I'm off grid, 12 years on first set of batteries, but they are on there way out, need to start gender to weld etc etc. Inverter failed costing $700aud to repair plus 2 weeks on generators. Generator battery fails at an incovenient time. Stress over lack of power when it's raining and have visitors

give me the grid any day, life has more to it than the cost of electricity.

[Ampster]

About a dozen people participated in this thread and it had almost 500 views. Does anyone know what the views are of those lurkers?

[tom rickard]

So in summary:

The original poster asked how to maximise the life of his batteries.

He was berated by a few others as being stupid, and a time waster for daring to ask that question.

A few statements were made that it was physically impossible for a battery to return more energy than was used in its creation.

This was refuted and backed up by anecdotal evidence as well as reference to scientific study.

When shown to be wrong, the perpetrators of the incorrect statements attempt to deflect by changing subject or playing victim.

Conclusion:
You can get cheaper power from battery/solar than from grid-connect, but for some unknown reason a few people will not like it..