Is this the future of Solar - use your EV as your backup battery for your home?

[4myr]

Maybe you already heard about this Canadian company that soon will introduce this amazing product in California, called dcbel r16.

 

Is this the future of solar? No need for Tesla powerwalls or buy separately a solar inverter and an EV fast charging station.

Use your EV as your backup battery for your home.

 

What is it:

- 15kw dual string solar inverter

- EV charger [AC and fast charging DC]

- use your EV as a backup battery for your home, as the flow is bi-directional, from grid to EV, and from EV to grid [home].

 

At the moment only Chademo EV cars [e.g. Nissan Leaf & Mitsubishi Outlander PHEV] supports bi-directional flow. Expected price in US is 6,000 USD.

 

Maybe this is a dream that soon will be reality. GB/T [Chinese DC charging standard] has also adopted bi-directional charging, is now fully compatible to Chademo. Order an upgraded Dongfeng EX1 EV car with bidirectional charging at Alibaba. Fill up your roof with max 20kwp solar panels. You will have a complete system with a better ROI than having only grid-tied solar electricity for your home.

[DJ54]

The F-150 Lightning's 9.6 kW of Intelligent Backup Power can provide full-home power for up to three days on a full charge of battery. ...May 20, 2564 BE

[sezze]

The bidirectional charging is available in most electric vehicles i know of . You do need a bidirectional charger for it also , and that's not all around just yet .

Yes it is the future of solar and electric vehicles , some cities in Europe ( i think in Netherlands ) are already trying this on big scale , meaning multiple chargers in city area , leveling all power inside the grid , so somebody can use a fast charge without draining the net , or houses in the same neighborhood . If your car is in , the you do get your charge but if somebody uses a fast charge , then part of it goes out again . In order to work , there have to be enough cars on the grid , but so far it has been working fine .

 

[007 RED]

This topic was the feature of one of BBC's technology programmes last November.  It appears that the use of an EV's battery for home use is currently being tried/tested in the UK.  At present the cost of the installation is being heavily subsidised by the company who running the trial, and if you wanted to purchase the system, it would set you back around 6,000 GBP, if I recall correctly.

 

https://www.bbc.co.uk/programmes/p08zc55j

[Yellowtail]

Seems like a good idea, but it would certainly void the manufacturer's warranty on your batteries ...

 

And also, would your batteries not be low in the morning if you had to use the car?

 

 

Edited July 10, 2021 by Yellowtail
added text

[VocalNeal]

All utilities would like to store energy during off-peak times. Some pump water uphill etc.. 

 

If they need to do it on a large scale they will offer the equipment.

[Yellowtail]

43 minutes ago, VocalNeal said:

All utilities would like to store energy during off-peak times. Some pump water uphill etc.. 

 

If they need to do it on a large scale they will offer the equipment.

 

The  school I went to refrigerated water at night to provide cooling during the day as they could buy power at night much cheaper. 

[Jonathan Fairfield]

18 hours ago, DJ54 said:

The F-150 Lightning's 9.6 kW of Intelligent Backup Power can provide full-home power for up to three days on a full charge of battery. ...May 20, 2564 BE

Good video here on that:

 

 

[tjo o tjim]

Fundamentally it is an inefficient solution— good for an emergency but not necessarily every-day use. The benefit of stationary batteries is they are in the same place by definition as the solar power. 

[Yellowtail]

7 minutes ago, tjo o tjim said:

Fundamentally it is an inefficient solution— good for an emergency but not necessarily every-day use. The benefit of stationary batteries is they are in the same place by definition as the solar power. 

And one would assume they are stored and operated under optimum condition.

 

But people love to think they are getting something for nothing.

[Bob12345]

18 hours ago, tjo o tjim said:

Fundamentally it is an inefficient solution— good for an emergency but not necessarily every-day use. The benefit of stationary batteries is they are in the same place by definition as the solar power. 

Not sure how it is where you live, but I got a power outage maybe once a month only.

So i certainly don't need it for every-day use, and would prefer to avoid buying expensive stationary batteries. 

 

It would be a nice backup system for living on-grid with only a few solar panels.

That seems to be the first step, at a later stage we should see if every house can survive off-grid and create its own electricity year round. 

[Yellowtail]

3 minutes ago, Bob12345 said:

Not sure how it is where you live, but I got a power outage maybe once a month only.

So i certainly don't need it for every-day use, and would prefer to avoid buying expensive stationary batteries. 

 

It would be a nice backup system for living on-grid with only a few solar panels.

That seems to be the first step, at a later stage we should see if every house can survive off-grid and create its own electricity year round. 

What about all the condos?

[chilly07]

I just keep old car batteries charged up for when the power cuts- is this the same?

[Yellowtail]

18 minutes ago, chilly07 said:

I just keep old car batteries charged up for when the power cuts- is this the same?

Similar, but what you do is just cheaper and more environmentally friendly.

[MrJ2U]

Those can only be charged so many times as they degrade.  I imagine there many times more expensive than off the shelf batteries.

 

If you can afford a Tesla why not get seperate batteries for your house solar set-up?  

[Bob12345]

On 7/11/2021 at 10:58 AM, Yellowtail said:

What about all the condos?

What about them?

 

Just pointing out that this was never meant to be the ultimate solution to every problem, its only a first step: use your EV as a backup in case of a power outage when you live in a house. Its not perfect or applicable for every place and every situation, but that is also not the goal at the moment.

[Yellowtail]

22 minutes ago, Bob12345 said:

What about them?

 

Just pointing out that this was never meant to be the ultimate solution to every problem, its only a first step: use your EV as a backup in case of a power outage when you live in a house. Its not perfect or applicable for every place and every situation, but that is also not the goal at the moment.

Again, would using your EV as a back-up not void the EV battery's warranty?

 

Assuming there were a power outage at night, how would one drive to work in the morning?

 

If your wife were home, and you were at work with the car, what would she do in the event of a power outage? 

 

If you were at home and your wife were out shopping with the car, what would you do in the event of a power outage?

 

If you and your wife were home and you were getting ready to leave for work and the power went out, how would you get to work? 

 

 

 

$6,000 would go a long way to install a UPS that utilizes lead-acid batteries.

 

 

 

[tjo o tjim]

21 hours ago, Yellowtail said:

Again, would using your EV as a back-up not void the EV battery's warranty?

 

Assuming there were a power outage at night, how would one drive to work in the morning?

 

If your wife were home, and you were at work with the car, what would she do in the event of a power outage? 

 

If you were at home and your wife were out shopping with the car, what would you do in the event of a power outage?

 

If you and your wife were home and you were getting ready to leave for work and the power went out, how would you get to work? 

 

$6,000 would go a long way to install a UPS that utilizes lead-acid batteries.

V2H is a great solution to an emergency event— but most people can just run a small inverter from their 12V plug to cover essentials. What it does not do is let you effectively use your rooftop solar when the grid is down… or your appliances as noted above. 
 

But, if you are actually going to cycle the batteries (to maximize self-consumption of PV and rely less on spinning the meter backwards) you would be better off with LFPs than Lead Acid. 

[Yellowtail]

30 minutes ago, tjo o tjim said:

V2H is a great solution to an emergency event— but most people can just run a small inverter from their 12V plug to cover essentials. What it does not do is let you effectively use your rooftop solar when the grid is down… or your appliances as noted above. 
 

But, if you are actually going to cycle the batteries (to maximize self-consumption of PV and rely less on spinning the meter backwards) you would be better off with LFPs than Lead Acid. 

For much less than $6,000 one could buy a gen-set for power outs that will last much longer than batteries. 

 

What are the benefits of LPFs over deep-cycle lead-acids for storing excess solar?

[Crossy]

41 minutes ago, Yellowtail said:

What are the benefits of LPFs over deep-cycle lead-acids for storing excess solar?

 

Longevity (cycles), zero maintenance, and you can go to better than 80% discharge without killing them.

 

They are also rapidly approaching the price of lead acid on an available storage basis.

[Yellowtail]

1 hour ago, Crossy said:

 

Longevity (cycles), zero maintenance, and you can go to better than 80% discharge without killing them.

 

They are also rapidly approaching the price of lead acid on an available storage basis.

 

How far can you discharge deep-cycle lead-acids without killing them? 

 

I see the maintenance issues, but which hold up better in the heat? Incidentally I think it would be pretty easy cheap and easy to use a chiller to keep the batteries cool.

 

How close are they price-wise now? I assumed the only advantage to lead-acid would be cost. 

 

I think a case could be made to build very large lead-acids with refurbishable plates...

 

 

[Crossy]

Most solar enthusiasts suggest limiting you lead-acids to 50% discharge for best life.

 

Lithium are better in the heat (but still don't like it), they definitely do not like the cold (not an issue here).

 

Any form of active cooling is going to use your valuable solar energy of course.

 

Value wise, if you don't mind using recycled vehicle batteries (with loads of life left, they tell us) lithium is very competitive on a stored watt for watt basis, but the cost of new cells is falling rapidly.

 

I got some used golf-cart LiFePO4 cells for experimental purposes for 1,500 Baht each for 200Ah. I've not completed a capacity test yet but even if they only measure 100Ah I would need 200Ah of lead-acid. My 200Ah (or whatever) 48V pack cost 25,500 Baht including a 100A BMS (there are better deals to be had, but they are very dynamic). 

 

The equivalent lead acid (new 120Ah batteries) would run around 31,000 Baht for (hopefully) about the same number of cycles before they die.

[Bob12345]

On 7/12/2021 at 2:25 PM, Yellowtail said:

Again, would using your EV as a back-up not void the EV battery's warranty?

 

Assuming there were a power outage at night, how would one drive to work in the morning?

 

If your wife were home, and you were at work with the car, what would she do in the event of a power outage? 

 

If you were at home and your wife were out shopping with the car, what would you do in the event of a power outage?

 

If you and your wife were home and you were getting ready to leave for work and the power went out, how would you get to work? 

 

 

 

$6,000 would go a long way to install a UPS that utilizes lead-acid batteries.

 

 

 

Again, it is a solution for a specific situation. Not more, not less.

 

But what if the sun explodes, dinosaurs come back, or rice wont grow? No, in those cases using your EV as backup doesnt help either.

[Yellowtail]

8 minutes ago, Bob12345 said:

Again, it is a solution for a specific situation. Not more, not less.

What might the specific situation be? It seemed like a good idea when I read it, but the more I think about it, the less sense it makes. 

 

I guess if you worked graveyard and could charge your battery all day at home using solar, but still the house is left without a backup anytime the car is gone. 

 

8 minutes ago, Bob12345 said:

But what if the sun explodes, dinosaurs come back, or rice wont grow? No, in those cases using your EV as backup doesnt help either.

I assume you throw this out in a feeble attempt to discount my position as you are (apparently) unable to formulate a response that actually addresses anything I've said. 

 

 

[driver52]

4 hours ago, Crossy said:

I got some used golf-cart LiFePO4 cells for experimental purposes for 1,500 Baht each for 200Ah

ACE! where did you manage to pick them up that cheap?

re the actual topic, doesn't like a clever idea to me where sun is so plentiful and panels are so cheap?

Edited July 13, 2021 by driver52

[Crossy]

9 hours ago, driver52 said:

ACE! where did you manage to pick them up that cheap?

 

Here https://www.lazada.co.th/products/i2527489409-s8982895965.html but there are a number of Lazada sellers with the same cells and the same text etc. Evidently someone brought in a lot.

 

I've got one on capacity test at the mo, but my tester only does 6A charge (it's nearly full now), a 20A discharge test to follow (should be about 10 hours).

[Bob12345]

15 hours ago, Yellowtail said:

I assume you throw this out in a feeble attempt to discount my position as you are (apparently) unable to formulate a response that actually addresses anything I've said. 

I get the feeling i am completely wasting my time.

Bye.

Edited July 14, 2021 by Bob12345

[tjo o tjim]

22 hours ago, Yellowtail said:

For much less than $6,000 one could buy a gen-set for power outs that will last much longer than batteries. 

Yes, a genset is going to be cheaper up front. But, you need to run it monthly, overhaul it periodically, and find away to safely store >>100L of gasoline, while rotating the storage to make sure it doesn’t go bad. Or, you can spend more and go for propane to lower maintenance issues, but you add some complexity. 
 

With a stationary battery you can have something that just works reliably for 10+ years, with zero maintenance for LFP. 

[Yellowtail]

4 hours ago, Bob12345 said:

I get the feeling i am completely wasting my time.

Bye.

I assume you throw this out in a feeble attempt to discount my position as you are (apparently) unable to formulate a response that actually addresses anything I've said. 

[Yellowtail]

30 minutes ago, tjo o tjim said:

Yes, a genset is going to be cheaper up front. But, you need to run it monthly,

Yes, but only if you do not have to actually use it. IF you have frequent power-outs this would not be a concern.

 

30 minutes ago, tjo o tjim said:

overhaul it periodically,

As a back-up you would likely never have to overhaul it. You would want to change the oil every year or two.

 

30 minutes ago, tjo o tjim said:

and find away to safely store >>100L of gasoline, while rotating the storage to make sure it doesn’t go bad.

Greater than 100 liters? How long would you expect the batteries provide back-up power? 

 

30 minutes ago, tjo o tjim said:

Or, you can spend more and go for propane to lower maintenance issues, but you add some complexity.

That's a good idea. Always have an extra LP tank anyway.

 

30 minutes ago, tjo o tjim said:

With a stationary battery you can have something that just works reliably for 10+ years, with zero maintenance for LFP. 

The topic is using your car's batteries as a back-up in the event of a power-out, not using stationary batteries as a back-up or using stationary batteries to store excess solar power and work as a back-up. 

 

My position is that using your car battery as a back-up in the event of a power-out seems ridiculous for all the reasons I have pointed out.

 

I have never run any numbers on using batteries to store excess solar AND work as a backup, and this might make perfect sense, but I would bet it makes little sense to use batteries strictly as a back-up.

 

I can buy a generator that will run everything in my home (including the air-conditioner) indefinitely for under a thousand dollars. How much would it cost for enough batteries to power my home (including the air-conditioner) for just an hour?

 

To be clear, I have no generator and no back-up. I do not think I need a back-up, and I am not advocating people install generators or batteries. I think people should spend their money as they see fit.