let's talk about battery banks- I reckon the "they aren't worth it" thing is wrong

[PVfarmer]

(b) (PV only) does include the remaining POCO charges for 20 years, it is still cheaper than (c) (PV plus batteries).

This is a true apples to apples comparison.

Ok, but you aren't subtracting the oranges! :huh:

a) Is a typical electric bill that people are trying to avoid by using renewable energy. It's just a price for using 240,000kWh over 20 years. (Golly that seems like a lot!)
b) Is a typical PV setup. If it costs $24000 over 20 years...what happened to the payback period? Payback is the first thing everyone wants to know.
So yes, the LCOE was 15 cents/kWh. But the fact that you did not pay the POCO is what allows payback/break-even/then savings coming in (savings on no bill. If POCO pays you for extra, even better.
c) Is a typical PV/BESS setup. It may cost more up front, but a zero bill increases your savings, so b) and c) could have the exact same payback period depending on the variables, but after you hit payback point, you will be "saving more" with c).
---

Originally Posted by PVfarmer You simply aren't listening. So the whole USA is just one state that has the same amount of sun and same POCO price?
Really?
No.


Did I say that?
No.
There are very few places in the US where that area
A> does not have cheap power (ex. $.15/kwh or less)
AND
B> does not have net metering.

States with more than $.15/kwh like CA have net metering.
States without net metering like TX have cheap power.

The amount of sun is actually irrelevant to discussions about whether batteries are economically feasible.

The example I gave (Tesla using battery storage at their plant) would be a great demonstration of the capacity of their battery packs being sufficient to handle a large industrial situation. There's no lying in any part of that. Showing off technology for your company is generally considered to be PR (or possibly advertising/marketing when it is more directly leading to increased sales/profits)

I was saying practically the opposite.
That companies are primarily concerned with their bottom line.
And anything that isn't about their bottom line is PR.
Making donations to good causes? PR.
Using 'green' power even when it's more expensive? PR.

If you think those non-profit-minded things *aren't* PR, then what would you call it?
(And whatever phrase you want to use for those things, you can just substitute it for where I've used the term "PR")

Selling people expensive stuff that doesn't perform as promised is a good business plan?
So what promised performance are you talking about?
IF you're talking about Tesla's powerwall, I expect it will perform exactly as promised. They promise cycles and number of kwh. They do NOT promise that you'll save money if you buy one from them.

BTW - I will point out that you don't actually show any counter examples to my assertions. (ie. a place in the US where it actually *would* be economically beneficial to install batteries. I think in an earlier post you may have suggested CA as such an example, but since we have net metering here it definitely isn't economically beneficial to install a battery system. (Not that people won't install them anyhow here in CA - many people do things for other than economic reasons)

Did I say that?
No.
There are very few places in the US where that area

"Did I say that? No. So I'll say it again"....
:huh: That's what you typed!
---

The rate in California is 12.46 cents.
---

The amount of sun is actually irrelevant
That is actually 100% wrong! Alaska=Albuquerque? Nope.
---

Yes, Tesla had a big PR event when they unveiled their Powerwall. Now they are marketing them, which is a crazy scheme they have involving selling them.
If they are lying in their marketing/ads (as you are implying by saying IT DOESN'T WORK) then they will have to do more PR to explain why they made a mistake/lied.
But you yourself say they'll perform as promised- they aren't promising "this battery will store energy, but not save you any money. Try it!"
---

That companies are primarily concerned with their bottom line.
And anything that isn't about their bottom line is PR.
Business schools teach profit maximization, transferring wealth from customers
to owners, because that is what business does.
On the other hand, PR teaches relationship and reputation building in ways that
lead to profits. PR assumes a business has vested interested in ethics. We
know, of course, that this isn’t true.
http://www.online-pr.com/Holding/Public_Relations_and_Profit_article.pdf

So there we see that PR does in fact have something to do with the bottom line.
---

They do NOT promise that you'll save money if you buy one from them.
So then why would you buy one?
It's YOU saying "you won't save money".
No company has ever said "buy our thing, it won't save you any money or do anything for you really, but it sure looks real nice"
---

BTW - I will point out that you don't actually show any counter examples to my assertions.

A picture is worth over 14 million people.http://www.hikenewengland.com/images/MasterNewEnglandMap.gif

 

[iwire]

[/I]A picture is worth over 14 million people.http://www.hikenewengland.com/images/MasterNewEnglandMap.gif

And a map without info is worthless.

I tend to be blunt, you seem to be trolling not looking for answers.

Good luck.

 

[jaggedben]

The amount of sun is actually irrelevant to discussions about whether batteries are economically feasible.

Well, it affects the LCOE of PV, among many other factors. But for the purposes of this discussion we state the PV LCOE as a given and leave it at that.

 

[wwhitney]

a) Is a typical electric bill that people are trying to avoid by using renewable energy. It's just a price for using 240,000kWh over 20 years. (Golly that seems like a lot!)
b) Is a typical PV setup. If it costs $24000 over 20 years...what happened to the payback period?

Let's keep the numbers straight. (A) is $36K as $150/month. (B) is $18K as $12K up front plus $25/month.

If you want the payback on the $12K PV, your monthly savings in B is $125/month, so that takes 8 years.

But we don't really need to look at payback for this analysis. I'm accounting for all costs over the 20 year period. Whichever option has the lowest costs over the 20 year period wins.

So yes, the LCOE was 15 cents/kWh.

No, the LCOE in my example was $0.05/kWh. Please, let's keep the numbers straight. With a POCO price of $0.15/kWh and a PV LCOE of $0.15/kWh, PV would be a wash financially.

c) Is a typical PV/BESS setup. It may cost more up front, but a zero bill increases your savings, so b) and c) could have the exact same payback period depending on the variables, but after you hit payback point, you will be "saving more" with c).

I'm looking at the bottom line, which is total costs over 20 years. 20 years is the lifetime of the equipment, after that it will have died and you'll be back where you started. No more equipment, no more savings. 20 years is the assumed lifetime of the PV, the battery system will probably get replaced 3 times over that 20 years.

If you want to look at it from a payback point of view, option (c) costs $24K but you save $150/month. The payback period is 13 years and 4 months, longer than the PV system. You are correct that the savings per month is greater than in the PV only option, but you paid a lot more upfront, as evidenced by the longer payback period. In fact, option (c) never "catches" up with option (b) before the equipment dies. At the end of the 20 year period, you are still behind $6,000.

But this payback point view of is unnecessarily complicated. Just look at total costs over the lifetime of the equipment for the three different options. That's the bottom line, apples to apples. There are no oranges.

Cheers, Wayne

 

[PVfarmer]

And a map without info is worthless.

I tend to be blunt, you seem to be trolling not looking for answers.

Good luck.

Nothing wrong with being blunt.
Thanks for moderating, btw- you are good at it. I mean that sincerely, really.

I am in fact looking for answers- the correct ones.
Trolling is when someone...uses a red herring to "prove" a point (often a very specific point, with seemingly no reason to do so), while refusing to address the existence of said herring.
As in "net metering is the way it is always done and it doesn't work because..."
The because is just "because I said so".
When the person engaging in said activity posts no links at all, that's kind of a dead giveaway.

I don't believe "IT DOESN'T WORK" is correct, as it (still, after a couple of requests) isn't really backed up with anything but some vague statements sort of about how "there is only one type of situation in the entire USA".
So I posted a map of New England, since the previous link about how there are 14+ million people there with POCO rates over 20 cents didn't seem to register with the nay-sayer.
That doesn't take into account NY and NJ, what's that another 25-30 million people?
Of course, "it doesn't work" is based on...what? The LCOE of PV being over the average/arbitrary 15 cent POCO charge, which is potentially a high number in addition to both being arbitrary.
I still have zero clue, no idea where "it doesn't work" is coming from.
People wouldn't be doing it if it "didn't work", so to me it seems like someone is expressing their opinion repeatedly, not listening, for no apparent reason.
Net metering isn't the only way things are done, so "batteries don't work" fails by not acknowledging that people get incentives- dozens of different incentives in all 50 states except for perhaps Texas.

Why not say "the average POCO charge is 12.64 cents/kWh", and admit that people can still install PV when the LCOE is a bit higher, depending of course on the fact that, as we have agreed on, situations can be different for people across the street from each other?
Why not post a link that provides some relevant info?
Average POCO price is known....average install cost of PV can be found, average household usage also a constant...

If someone would like to explain why these two aren't true, or maybe update the 2010/2012 thing, please do! I'm good with this info here.

Policies for compensating behind-the-meter generation vary by State
Compensation. Customers effectively receive retail prices for the electricity they generate, as they are charged only for their net electricity usage (their consumption from the distribution system, over and above their onsite generation). In some States, customers receive wholesale prices (which are lower than retail prices) for their excess generation supplied to the distribution system.

(and in some states customers get more than wholesale, and some get more than retail. That is the truth.)
---
While participation is increasing, electric customers with net metering represented only 0.1% of all customers in 2010.
http://www.eia.gov/todayinenergy/detail.cfm?id=6270

 

[wwhitney]

If you want to look at it from a payback point of view, option (c) costs $24K but you save $150/month. The payback period is 13 years and 4 months, longer than the PV system. You are correct that the savings per month is greater than in the PV only option, but you paid a lot more upfront, as evidenced by the longer payback period. In fact, option (c) never "catches" up with option (b) before the equipment dies. At the end of the 20 year period, you are still behind $6,000.

To expand on this a little, option (a) (POCO only) is the baseline. So when we talk about "payback period", we mean the point at which the monthly savings versus baseline pay back for the upfront equipment costs. The savings after that are "profit" until the equipment dies.

Let's compare (b) (PV only) to (c) (PV plus batteries) from this point of view. Option (b) had a payback of 8 years--$12K in up front equipment costs for $125/month of savings. For the following 12 years, you get to save $125/month free and clear, or $18K. Then the equipment dies. Note that $18K is also the difference in the 20 year cost of option (b) versus option (a). Great, the math works out.

Now in option (c) the payback period is 13 years and 4 months--$24K in up front equipment costs and $150/month of savings. For the next 6 years 8 months you get to save $150/month free and clear, or $12K. Then the equipment dies. Note that $12K is also the difference in the 20 year cost of option (c) versus option (a). You saved some money, but not as much as with option (b).

If you want to "race" the two options, at the 13 year 4 month mark, option (c) has paid for itself, but option (b) would have already accumulated 5 years and 4 months of savings at $125/month, or $8K. From this point on option (c) saves $25/month more than option (b), but for it to catch up to the $8K lead of option (b) would take 320 months or 26 years 8 months. Sadly, the equipment dies after just 6 years 8 months, so option (c) never gets a chance to catch up with option (b).

Lastly, as far as whether or not "it works", you need to understand the analysis first before you are in a position to say whether it works. At least this simplified analysis which ignores the time value of money.

Cheers, Wayne

 

[PVfarmer]

Let's keep the numbers straight.

But we don't really need to look at payback for this analysis. I'm accounting for all costs over the 20 year period. Whichever option has the lowest costs over the 20 year period wins.

I'm looking at the bottom line, which is total costs over 20 years. 20 years is the lifetime of the equipment, after that it will have died and you'll be back where you started.
But this payback point view of is unnecessarily complicated. Just look at total costs over the lifetime of the equipment for the three different options. That's the bottom line, apples to apples. There are no oranges.

I hope you don't think I'm "trolling" you- we're having a friendly chat, while confusing the heck out of each other!
So where do you end up if you don't look at payback? When the LCOE is a positive number, because you didn't look at savings or payback or POCO rate/netmetered vs. cash incentives or anything compared to the LCOE (which is the correct way for the LCOE to be calculated....)
How do you even know if investing in the PV is worth it or not? I think if someone says "the LCOE is XX cents" the next question has to be "so what's the POCO rate?"
And then what's the usage.

Does this one sentence make sense? And if so, yes or no?
--> Over 20 years the LCOE is a constant, while the POCO price changes, and those two are what affects the amount of money in pocket, which must go from negative to positive (or at least zero in certain cases).

If you ignore the time value of money- what time is it? How can we meet up at the same place if our watches aren't in sync?!

 

[TommyO]

Well, sun exposure affects the LCOE of PV, among many other factors. But for the purposes of this discussion we state the PV LCOE as a given and leave it at that.

It does - BUT we're talking about the usefulness of batteries for residential use.
And the important numbers there are
* Sales price of power to the POCO
* Cost to store power
* Purchase price for power from the POCO

PV LCOE for the most part isn't going to be relevant, because assumably it will be cheaper than the sales and purchase price.
If it isn't, then installing solar at all (much less with batteries) is probably not a good idea.

 

[peter d]

I tend to be blunt, you seem to be trolling not looking for answers.

:thumbsup:

 

[TommyO]

No company has ever said "buy our thing, it won't save you any money or do anything for you really, but it sure looks real nice"

Hm - I thought jewelry companies were pretty much built with exactly that idea.

BTW - I will point out that you don't actually show any counter examples to my assertions.

A picture is worth over 14 million people.

Ok - so which state there has expensive power (over $.15/kwh) AND doesn't have net metering.
I understand that Maine has both cheap power AND net metering.
So that eliminates one of the states in your map on both counts.

 

[PVfarmer]

It does - BUT we're talking about the usefulness of batteries for residential use.
And the important numbers there are
* Sales price of power to the POCO
* Cost to store power
* Purchase price for power from the POCO

PV LCOE for the most part isn't going to be relevant, because assumably it will be cheaper ....

And what happens when you assume....?
PV LCOE isn't relevant because you didn't say what * * and * are! :happyyes:

You DID say that * * and * are always such that BESS is never a good option.

Ok - so which state there has expensive power (over $.15/kwh) AND doesn't have net metering.
I understand that Maine has both cheap power AND net metering.
So that eliminates one of the states in your map on both counts.

Then you said it is * * and * in Maine- still no actual numbers.
Maybe you should call these people and warn them that they are going to go bankrupt with this crazy BESS scheme.
Guess where they are?
Maine!
http://www.mooseheadpowersystems.com/gridTieSystems.htm

According to you, they are just doing it for PR. I doubt they'd agree.

 

[PVfarmer]

And the important numbers there are
* Sales price of power to the POCO
* Cost to store power
* Purchase price for power from the POCO

PV LCOE for the most part isn't going to be relevant

If, in Maine-
* Sales price of power to the POCO = 15 cents
* Cost to store power = 10 cents
* Purchase price for power from the POCO =15 cents...

The LCOE does in fact matter- it has to be below 5 cents or you are wasting your time.
Right?

 

[wwhitney]

So where do you end up if you don't look at payback?

Please carefully reread all my posts in this thread. If you don't understand a particular point, ask me about that instead of introducing other issues. If you take the time to do that, it should clear up your confusion.

When the LCOE is a positive number, because you didn't look at savings or payback or POCO rate/netmetered vs. cash incentives or anything compared to the LCOE (which is the correct way for the LCOE to be calculated....)

Correct, that is what LCOE means, other ways of calculating it are wrong.

How do you even know if investing in the PV is worth it or not? I think if someone says "the LCOE is XX cents" the next question has to be "so what's the POCO rate?"

Right.

Does this one sentence make sense? And if so, yes or no?
--> Over 20 years the LCOE is a constant, while the POCO price changes, and those two are what affects the amount of money in pocket, which must go from negative to positive (or at least zero in certain cases).

Well, at the beginning of your ownership, you can only estimate the PV LCOE (you don't know the actual lifetime) and you can only estimate the future POCO prices (you don't know how they will change). So for the simple example, I'm just assuming the PV lasts exactly 20 years, and that the POCO prices don't change. Once you understand this example, we can try to address those complexities.

If you ignore the time value of money- what time is it? How can we meet up at the same place if our watches aren't in sync?!

Ignoring the time value of money means just adding up all the payments and credits, ignoring when those payments and credit occur. it is working under the assumption that $1 today is worth the same as $1 in 10 years or any time in the future. That's obviously not true, but it simplifies all the math. Again, let's understand this version before worrying about the time value of money.

Good luck.

Yours,
Wayne

 

[ggunn]

Let's look at this from the other side and eliminate the situations where we can all agree that batteries as an adjunct to PV are definitely a bad idea, OK? I'll start:

1) For a facility (home or business) where the facility immediately uses all the power the PV system produces, i.e., the meter never "runs backwards".
2) For areas where there is net metering, i.e., the meter runs backwards and forwards and the utility is only concerned with the bottom line at the end of the month - grid storage is free.

 

[TommyO]

If, in Maine-
* Sales price of power to the POCO = 15 cents
* Cost to store power = 10 cents
* Purchase price for power from the POCO =15 cents...

The LCOE does in fact matter- it has to be below 5 cents or you are wasting your time.
Right?

No - you're still wasting your time if it's $.01/kwh or $.14/kwh

Let's say I need 10kwh at night. (really could use any number, but I'll use 10 because it makes the math simple and you can scale up/down to any amount and the result is the same)
Let's shorten LCOE for PV to "L" in the below equations.

Scenario A: I buy from the POCO (no solar, no batteries)
Cost: 10 * .15 = $1.50 per night

Scenario B: I generate the power, sell the power and buy it back at the same price
Cost: 10*L
$.10 if L=$.01/kwh
$1.40 if L=$1.40/kwh

Now, you might say "Why 10*L?", well it is the sum of:
10*L = cost to generate
10*-.15 = money from selling to POCO
10*.15 = purchase of power from POCO
The last two terms cancel (as expected with net metering)

Scenario C: I generate the power, I put it into batteries and then use it.
Cost: 10*L + 10*$.10
$1.10 if L=$.01/kwh
$2.40 if L=$1.40/kwh


Scenario B (PV, but no batteries) wins whether the LCOE PV is $.01 or $.14. It always is better than scenario C because your selling and purchase prices are equal (net metering)

 

[TommyO]

And what happens when you assume....?
PV LCOE isn't relevant because you didn't say what * * and * are!

???

I understand that Maine has both cheap power AND net metering.
So that eliminates one of the states in your map on both counts.

Then you said it is * * and * in Maine- still no actual numbers.

I assume from context that the "* *" and "*" are cheap power and net metering.

As for cheap power:
$.128/kwh is price of one POCO in Maine - http://www2.cmpco.com/EnergyCalculator/input.jsp

And maybe they might get as high as $.15/kwh - http://www.centralmaine.com/2014/10/06/maine-electric-rates-to-skyrocket/ (but that's so "high" that it warrants a news story, yet still is what I have categorized as "cheap")

As for net metering - here's some Maine POCO's pages about net metering:
http://www.cmpco.com/SuppliersAndPa...Market/BusinessInMaine/netenergymetering.html
http://www.emeramaine.com/residential/rates/bhe-net-energy-billing/

Maybe you should call these people and warn them that they are going to go bankrupt with this crazy BESS scheme.
...
http://www.mooseheadpowersystems.com/gridTieSystems.htm

According to you, they are just doing it for PR. I doubt they'd agree.

No - if they were paying for the batteries themselves, I'd say they were doing it for PR.
They're not - they're advertising that they will sell battery systems to anyone who wants to buy them.
In Maine, there are places where there aren't POCO lines nearby, and a battery system (off-the-grid) makes sense.
There's probably also places where POCO power is unreliable because lines get taken out in storms, and therefore a near-off-grid system is nice because they can run the generator a little less.

I'm certainly not predicting that they'll go bankrupt - BUT I bet they aren't selling many battery systems that are grid tied either. (Instead they're likely selling off-grid systems and grid-tie systems without batteries and probably making a nice profit at it)

 

[TommyO]

Let's look at this from the other side and eliminate the situations where we can all agree that batteries as an adjunct to PV are definitely a bad idea, OK? I'll start:

1) For a facility (home or business) where the facility immediately uses all the power the PV system produces, i.e., the meter never "runs backwards".
2) For areas where there is net metering, i.e., the meter runs backwards and forwards and the utility is only concerned with the bottom line at the end of the month - grid storage is free.

3) When the cost of storing the power is more than the cost of buying it from the POCO

 

[PVfarmer]

No - you're still wasting your time if it's $.01/kwh or $.14/kwh

Let's say I need 10kwh at night. (really could use any number, but I'll use 10 because it makes the math simple and you can scale up/down to any amount and the result is the same)
Let's shorten LCOE for PV to "L" in the below equations.

Scenario A: I buy from the POCO (no solar, no batteries)
Cost: 10 * .15 = $1.50 per night

Scenario B: I generate the power, sell the power and buy it back at the same price
Cost: 10*L
$.10 if L=$.01/kwh
$1.40 if L=$1.40/kwh

Now, you might say "Why 10*L?", well it is the sum of:
10*L = cost to generate
10*-.15 = money from selling to POCO
10*.15 = purchase of power from POCO
The last two terms cancel (as expected with net metering)

Scenario C: I generate the power, I put it into batteries and then use it.
Cost: 10*L + 10*$.10
$1.10 if L=$.01/kwh
$2.40 if L=$1.40/kwh


Scenario B (PV, but no batteries) wins whether the LCOE PV is $.01 or $.14. It always is better than scenario C because your selling and purchase prices are equal (net metering)

Um...what? PV is only worth it in Maine if the cost is zero?
That makes zero sense!

Let's try again. Person X lives in Maine and wants a PV system. Should they get PV or PV/BESS?
If, in Maine-
* Sales price of power to the POCO = 15 cents
* Cost to store power (BESS) = 7 cents
* Purchase price for power from the POCO =15 cents...

Where's the rest of the cost? Oh right, the panels and BOS.
So panels + BOS = 7 cents.
Total cost = 14 cents.
14 < 15. Good deal.
Right?

If panels + BOS = 10 cents...BESS is the same...total cost = 17 cents.
STILL a good deal because that 17 cents isn't the whole story- like I keep saying, there is no electric bill!
The fact that there is no bill is what allows you to pay back for the PV, BESS or not.
So yes, believe it or not, you can spend MORE on PV or PV/BESS than your electricity costs.
The amount you originally spent on panels, BOS, BESS goes down, and eventually becomes profit (or just savings when net metering only). That's kinda the whole idea!

If you pay 15 cents to POCO and spend 17 on PV etc:
Year 1: You are paying 2 cents more than you were. However, you saved X by not paying the electric bill. That X is your "payback money"- it really makes the "C" in LCOE go down, which is why LCOE is not really the whole story.
Year 2: You are paying 1.5 more.
Year 3: 1 cent more
Year 4: .5 cents
Year 5: 0 cents
Year 6: You broke even the year before, now you are making .5 cents.

It really seems pretty straightforward.

 

[ggunn]

I freely admit that I don't slog through all the laborious numerical analyses (sorry) but a factor I haven't seen in the ones I have read through is just how much storage we are talking about. For any battery storage hardware there will be some fixed costs that do not depend on the magnitude of the storage needed, while the monetary advantage (if any) will be tied inextricably to that quantity. You can't just say that storage in batteries costs some flat $/kWh down to 1 kWh; if you are only generating a kWh above your usage during daylight hours, batteries are not economically viable no matter what else is in play, even if the POCO just takes it without compensating you for it.

 

[ggunn]

That's the way it works, and presently the VOS is 10.7 cents per kWh. To their way of thinking, solar should not be worth more to you than to someone else just because you use more energy.

I was incorrect in the way I described Austin Energy's Value Of Solar. What they do is charge you for the energy your home uses at whatever tier you are on irrespective of where it comes from as one transaction, and then they credit you for your PV system's production at the VOS $/kWh as another transaction. Since AE is a municipally owned utility, that credit is applied to your electric bill, your water/wastewater bill, your garbage/recycling pickup bill, and any other municipal services charges you might incur. I don't think it counts against parking tickets, though.

It's very much like a Feed In Tariff, although it's all done behind the utility meter. I apologize for any confusion I may have caused by my misstatements.