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Abusing free nights electricity plan with batteries

Cabin Rising said:
You are getting fudged with TXU. I would suggest shopping around for a better rate. That is more than double what any of the off brand companies charge. TXU is the highest there is in the state. Most other plans are around $0.06-0.11 per kw.

A friend just got off TXU a few months ago. Electric bill went from average of $450.00 to $86.00 per month in the last two statements.
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I don't have TXU, they're just the ones with the free nights plan. I pay about $0.14/kwh. Still expensive, but it isn't $0.30/kwh that TXU charges on the nights free plan. I just renewed last month and this was the cheapest I could find.
1201 said:
This will be my last post in this thread.

Your goal is to have no to almost no energy bill. There are many ways to get there. 15kw of pv in Texas should make about 75kwh per day. That can be found for about $5k before tax credit.
Op You keep going on about 200amp service . Do you actually know what your peak demand is? What's the point of having 200a worth of inverter if you only ever use 100a.

Nowadays you can buy 20kw of inverting power for $2200 before tax credit. Mounting for 15kw may cost $3k

So 5k for pv
2.2k for inverter
3k for mounting
$4k for 30kwh of battery
And $2k for balance of system

So let's say $12k after tax credit all in to almost zero out your bill and have backup power .

The free nights plan is iffy since there is nothing one can do if they change the terms but it's probably even cheaper to just get pv , off grid inverters and some battery storage and have basically no energy bill. What is the Poco going to do then- remove the meter? 😂

Seriously though in most places they can't do much if the pv system is not connected to the grid.
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I was more just thinking about if there's a way to get a good deal with the nights free plan if you charge up batteries at night. 200A isn't required, but someone brought it up earlier, so I started thinking about it in those terms. You can probably get some value out of a small system if you don't need to sustain 200A.
 
bobby3605 said:
I live in Texas, and one of the energy companies I can choose from is TXU energy. They have a plan where you get 100% free energy from 8pm to 4:59am. During the day the cost is 29.6 c/kwh, so I'd never want to use power during the day.
EFL: https://residential.txu.com/Handler...ype=EnergyFactsLabel&custClass=3&tdsp=CENTERP
I've been brainstorming about designing a battery backup system that can fill up during the night for free, then discharge during the day, so I'd have 100% free power (minus a $10/month base charge).
Assuming a power usage of 2000kwh/month, that works out to 67kwh per day. So I'd need to charge a 67kwh battery pack every night. 67kwh/day is way overkill, but I'm just brainstorming, so I'm trying to see what a theoretical reasonable maximum of the system would look like.
Also, that 67kwh is for a full 24 hours, but I only need batteries to last from 5am - 8pm. However, I'll leave it at 67kwh for brainstorming.
The battery I'm currently brainstorming with is the EVE MB30. https://www.alibaba.com/product-det...fferlist.topad_classic.d_title.87aa458eANU1mh
67kwh over 12 hours means the inverter needs to be able to sustain 5.583kwh, not too bad.
The inverter I'm currently brainstorming with is the Schneider Conext XW PRO 6.8KW. https://signaturesolar.com/schneider-conext-xw-pro-6-8kw-inverter-charger-48v-120-240v/
It can charge the batteries at 48v 120A on 120vac, so it can charge 67kwh in about 11.6 hours, which is barely within the 12 hour free nights window.
The inverter is a bit expensive, I don't know if there's a cheaper one that will work for this.
The payback period I've currently calculated is 3.2 years, and that's with an overkill amount of batteries.
I'd appreciate any feedback on this idea.
All of this would also be contingent on the power company not refusing to renew my contract after a year, or kicking me off even sooner than that. I didn't read anything in the fine print about banning this kind of usage.
I may be able to get the federal tax credit for this, so that's 30% off the price. Battery shipping will increase the price, and so will miscellaneous things like cables, battery BMS, and battery case.

EDIT:
Here is the spreadsheet I used for my calculations. https://docs.google.com/spreadsheet...mZqEpd6nbbDKSrW7RShEYtWl6QY8A/pub?output=xlsx
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Holy cow is there a limit? Might be time to upgrade your panel haha! I would pull every Watt hour possible :LOL: run some 50A cables to my neighbors and sell them the power during the day
 
bobby3605 said:
which is about the same as the DIY solution.
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Reminiscent of the build-your-own-computer days, when it went from "build a much better computer for half the price" to "if your time is worth nothing it's the same price as the Dell". Really happy with my EG4 ESS, though of course I want more batteries. 8*) #RangeAnxiety
 
This feels a lot like the cellphone 'unlimited data' plans, followed by the 'unlimited and this time we really mean it' plans (narrator: They didn't mean it).
 
You gotta be careful when looking at these "free nights" plans. A lot of them will still pass the TDU charge on to you at $.045403 (Oncor). Green Mountain, Reliant, and Direct Energy are a few that offer truly free nights but the rates, free times, and base charges differ so you need to know when you use more power to take advantage of it. My current plan has free nights from 8pm-6am. Direct Energy has a 12 hour free window from 9pm-9am but this is worse for me since I use a lot more energy at night in the summer. More morning in the winter but summers here in Texas are longer than winter.
 
I do this with 20kw of battery and 6.8kw XW Pro. I use Flagship power in TX. My contracted rate is around 14.2c but it averages to around 9c per kw. I have 1 AC unit(with soft start) on it and it works pretty good. You still have to pay for the TDU charges. The more you pull, the more the TDU charges. In June, 70% of the day time charges was free for me. The power company basis their estimates on 40% of the charges being at night. I have not decided on if I should go solar or have more batteries. The only way to get rid of TDU charges is via solar(I think)
 
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blueforce said:
You gotta be careful when looking at these "free nights" plans. A lot of them will still pass the TDU charge on to you at $.045403 (Oncor).
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blueforce said:
Green Mountain, Reliant, and Direct Energy are a few that offer truly free nights but the rates, free times, and base charges differ so you need to know when you use more power to take advantage of it. My current plan has free nights from 8pm-6am.
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So these providers don't pass on the TDU charges to you?

blueforce said:
Direct Energy has a 12 hour free window from 9pm-9am but this is worse for me since I use a lot more energy at night in the summer. More morning in the winter but summers here in Texas are longer than winter.
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I'd put in a system that covers one half of daily usage to get started but at $0.29/Kwh it still is over $0.14/Kwh which is what you are paying now. There is a reason it is priced at $0.29/Kwh and free nights.

Get greedy and they will boot you off. Instead, just slowly increase free usage and say you installed more efficient appliances if they question it.
 
wpns said:
They are not going to question it, they are just going to boot you off when it becomes untenable for them.
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Hard to know..different places do different things… where I’m at if your usage abruptly changes it can be because you live here half a year and go to Florida in winter… (summer people).

If something seems odd they may just send a truck out and look around ..( snooping)

If your meter goes down and they don’t know why ,a truck will be out very shortly to find out 2hats going on …( investigating)

If they suspect you’re up to some monkey business in some way , you get known …you don’t want to be known…( a usual suspect) .

No one is as anonymous as they used to be…every one can be watched or monitored by different groups… for whatever reason. if somthing is suspected…even if untrue….( big bro)…

Phone Co, , power Co, , cable Co, ins Co, building inspectors, Health dept, enviro people ,DSS, narcs, revenuers , and plenty other type alphabet people .( here comes the Fuzz)

It’s best to just try to be a good boy …!!! and don’t do nothin…or at least don’t appear to be Doin somthin…( don’t start nothin, won’t be nothin) …

Totally new world we got now….
 
bobby3605 said:
they're UL listed. The 5th picture has a UL certification.
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+1 for getting the correct understanding of whether cell or system level UL is what you need.

I just looked it up again for California for another forum member. R328 in residential code (which comes from a common code book that many states adopt) explicitly says 9540 is required, which is a system and not cell level certification.

There is a California state amendment to allow recycled EV batteries but that’s not what you’re looking at.

I’ll note that this is very well trodden discussion in this forum
 
An XW Pro, or two, would absolutely do this. There are two strategies to manage the power production for self-consumption as you describe:

1. Move all circuits in the house to a load panel powered by the XW Pros. Doing this gives you full control over prioritizing your power flow goals. A transfer switch or bypass using a PDP should be considered for powering your home through that new loads panel when the XW needs to be shut down, like for firmware updates.

-or-

2. Install an "external power meter", as Schneider refers to them. These devices, such as the WattNode, have clamps over the mains from the meter feeding your main panel. This strategy required nothing at all to be connected to the XW Pro(s) output. The Insight Gateway/Home/Facility is connected to the RS-485 modbus terminals on the meter. Insight can then be configured to manage power produced by the XW Pros feeding back to the grid side of the inverter, not to exceed the loads, so that power isn't flowing backward into the utility. This solution introduces some latency in how quickly the XW Pro(s) respond to load changes, so it can't be considered the optimal choice for efficiency. It does mitigate the need to move all the house circuits to a separate load panel. The attached document explains some options for this solution.

Closed loop communication between the Schneider Insight and the LiFePO4 battery BMS stack is generally canbus, like with Ruixu batteries. So, both devices can connect to Insight at the same time.

Edit: I should also point out that option 2 provides no backup for you when the grid goes down. The Inverter can only generate waveform to the output side. Option 1 gives you full backup autonomy.
 

Attachments

  • Self-Supply and Export Limiting Solution Guide.pdf
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What I've seen here is a lot of people who aren't in TX saying they will boot you off. Is there anyone in TX who has first-hand experience being kicked off a free nights plan?

These companies know they're will be a few, very very few, customers who will get more out than they put in but most people will generate some level of profit for them. ERCOT's wholesale price for electricity averages <$0.05/kwh and the price from 8pm-6am averages<$0.03/kwh and that's for the entire year.
 
blueforce said:
What I've seen here is a lot of people who aren't in TX saying they will boot you off. Is there anyone in TX who has first-hand experience being kicked off a free nights plan?

These companies know they're will be a few, very very few, customers who will get more out than they put in but most people will generate some level of profit for them. ERCOT's wholesale price for electricity averages <$0.05/kwh and the price from 8pm-6am averages<$0.03/kwh and that's for the entire year.
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You are correct, most folks won't build out a full battery system based on a 1-year contract, so the number of customers paying the $4.23/month minimum is going to be few and far between, so it'll just disappear in the noise. But they _could_ change the terms, or pass through higher night-time charges, or not renew the contract, and that's going to further dissuade folks from spending tens of thousands of dollars in the hopes of saving money. Looks like they'll also buy surplus solar, so that's good.
 
wpns said:
You are correct, most folks won't build out a full battery system based on a 1-year contract, so the number of customers paying the $4.23/month minimum is going to be few and far between, so it'll just disappear in the noise. But they _could_ change the terms, or pass through higher night-time charges, or not renew the contract, and that's going to further dissuade folks from spending tens of thousands of dollars in the hopes of saving money. Looks like they'll also buy surplus solar, so that's good.
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Can’t speak for Texas or the Caribbean, but the poco in my region ended some TOU programs and incentives.

They just totally cancelled it for everyone as their agreements ran out and stopped the programs.

I had heard about them years ago but payed little attention or really cared.. Untill I learned about them here on the forum while starting to build my system..

By the time I finally called to express interest and request info, they said
“ we don’t offer that anymore “ …

I guess I was just late for the dance … so what’s new…! .
 
blueforce said:
What I've seen here is a lot of people who aren't in TX saying they will boot you off. Is there anyone in TX who has first-hand experience being kicked off a free nights plan?

These companies know they're will be a few, very very few, customers who will get more out than they put in but most people will generate some level of profit for them. ERCOT's wholesale price for electricity averages <$0.05/kwh and the price from 8pm-6am averages<$0.03/kwh and that's for the entire year.
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@GregTR Is on a free nights plan and liking it, hasn't been kicked off yet. I haven't seen any evidence of anybody being kicked off yet either.

https://diysolarforum.com/threads/w...id-or-even-paid-to-consume.84840/post-1129358
 
When enough people start doing this, some brilliant young MBA in management will suggest bringing back the night time tariff.

It seems to me to be a fairly obvious trap to attract new customers.
When enough suckers have signed up, the bait is certain to vanish fairly suddenly.
Power utilities are not charitable non profit institutions !!
Enjoy it while you can, just don't get too greedy.

After you have built your very expensive system, the payback time might end up being a lot longer than you now predict.
Especially when you factor in that those very hard working batteries are not going to have an infinite lifetime.

What I do here, is I have a minimalist "off grid" system to provide basic essential regular house power.
I have some fairly large loads that are infrequently run, welder, lathe, milling machine, all three phase, and airconditioning that I only need to run for a few days each year during peak summer.

So I can get away with having a small 5Kw single phase inverter, and run all the big stuff straight off the grid.
The big stuff only runs for very short periods (averaged over a monthly basis) so the actual running cost is minimal even though a lot of peak surge amps are involved.

If the grid does go down, I can still live quite comfortably and inexpensively.
 
Warpspeed said:
What I do here, is I have a minimalist "off grid" system to provide basic essential regular house power
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Absolutely….what do I need , not what would be nice…there’s no end to that list …

I just want enough to be long term comfortable , know how to repair it and not be worried about payback..

Everything I own will out last me anyway…. If not I have spares put back…

J.
 
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