Tesla Powerwall

[RegGuheert]

Maybe I'm missing something, butit seems to me that you are talking out of both sides of your mouth here.

You're right, I am. I am also conflating two different things:

- Where I live, there is currently no backlash against net metering because there are very few subscribers who net meter. Also where I live (and where you live) one would need to greatly oversize (~5X normal size) one's PV array in order to meet all of one's needs in the dead of winter, even with a large battery bank. (So dropping fully off the grid with a battery bank is not nearly as trivial. Nine months of the year, no problem. The other three months are much more difficult without burning something to stay warm.)
- Elsewhere in areas where the climate is not as cold and there is a much higher market penetration of PV, the utilities ARE starting to penalize their net-metering customers AND these same customers have a much better chance of disconnecting from the grid (or at least shifting their production and/or generation to compensate for the utilities' new policies. (So expect defections from the grid as the utilities change their policies.)

Long-term, we (the net-metered PV population in general) should be willing and able to pay the proper amount for the maintanence of our "battery".

Sure, but how much is that? And in the future, that will be much easier to bear since the PV will be much cheaper than the break-even that it was four years ago when I bought or the 50% grid price that it is today.

Or invest in your own personal battery if you prefer.

This is where things get tricky. Does it make sense to have people in our climate install mulitple times the amount of PV that they need to cover their annual consumption and then pull that off the grid and operate from batteries only? IMO, that is an extremely wasteful approach, particularly at a time when PV penetration rates are low and that actual production could instead directly prevent the equivalent amount of production from coal. Simply put, standalone battery-based systems are extremely inefficient. So until the time that my PV generation starts to impact others, either in their bills or in the behavior of the grid, net metering is a decent compromise overall. It certainly is the most straightforward approach at this time.

 

[mjblazin]

These ideas of everyone having own solar panels and batteries reminds me of Chairman Mao's Great Leap Forward in the 1950's. Then the idea was every village get its own blast furnace. I have to believe these systems do not repeal economies of scale. Everybody getting his own battery seems to be an atrocious waste of expensive materials and the seedbed of a gigantic toxic waste problem. What happens when that garage catches fire from something nothing to do with battery? Will we send firemen in there? Who cleans that mess up after the fire? In Dallas, we have more than a few fine homes that burn to the ground, nothing standing. Who knows what will leak out of that battery assembly?

 

[Slow1]

These ideas of everyone having own solar panels and batteries reminds me of Chairman Mao's Great Leap Forward in the 1950's. Then the idea was every village get its own blast furnace. I have to believe these systems do not repeal economies of scale. Everybody getting his own battery seems to be an atrocious waste of expensive materials and the seedbed of a gigantic toxic waste problem. What happens when that garage catches fire from something nothing to do with battery? Will we send firemen in there? Who cleans that mess up after the fire? In Dallas, we have more than a few fine homes that burn to the ground, nothing standing. Who knows what will leak out of that battery assembly?

While I've never considered the toxic nature of a fire incident, I fully agree with your comments regarding economies of scale here. Batteries are all well and good but it clearly is more efficient to let my neighbor use the power when required (i.e. when I'm generating in sunlight) and offset some other source, then both draw off that alternate source at night. Even considering transmission losses I'm sure the battery is going to be less efficient end to end.

 

[dgpcolorado]

[While I've never considered the toxic nature of a fire incident, I fully agree with your comments regarding economies of scale here. Batteries are all well and good but it clearly is more efficient to let my neighbor use the power when required (i.e. when I'm generating in sunlight) and offset some other source, then both draw off that alternate source at night. Even considering transmission losses I'm sure the battery is going to be less efficient end to end.

If utilities are willing (or required) to continue to allow net metering, it seems that utility-scale storage would be more practical, whether huge batteries or something else, such as pumped storage. But if the utilities start pushing back against net metering then I think more of their customers will go off-grid.

 

[Slow1]

[While I've never considered the toxic nature of a fire incident, I fully agree with your comments regarding economies of scale here. Batteries are all well and good but it clearly is more efficient to let my neighbor use the power when required (i.e. when I'm generating in sunlight) and offset some other source, then both draw off that alternate source at night. Even considering transmission losses I'm sure the battery is going to be less efficient end to end.

If utilities are willing (or required) to continue to allow net metering, it seems that utility-scale storage would be more practical, whether huge batteries or something else, such as pumped storage. But if the utilities start pushing back against net metering then I think more of their customers will go off-grid.

I agree. I really would NOT want to see a situation where it is better for individuals to go off-grid as I can see no way that it would be more efficient as a whole. Utilities are clearly being challenged to balance things - politicians and others creating incentives to push what they perceive as optimal behavior and/or satisfy various client groups can make for some very odd and complex optimization scenarios. In the end "fair share" of the costs ends up being very subjective eh?

However, when push comes to shove I would go off grid if it made sense - unfortunately given current tech/costs the optimum solution would likely involve at least some ICE generation in the mix. Not good for environment etc, but I could see myself building a solution with PV, Batteries, and a small generator to cover re-charging the batteries when required after a string of low-sun days.

 

[edatoakrun]

...Does it make sense to have people in our climate install mulitple times the amount of PV that they need to cover their annual consumption and then pull that off the grid and operate from batteries only? IMO, that is an extremely wasteful approach...

I think you are missing the possibility of using a BEV as your link to the grid, allowing you to download or upload kWh over the road, rather than over a wire.

Obviously, if the actual costs of bringing kWh over the grid to your home are low, this is uneconomic.

But for millions of homes in remote locations (like my own) the actual grid costs are very high, but currently subsidized by other ratepayers.

So, I hope that at some point my utility (PG&E) which loses a great deal of $ each year providing me service will offer me an incentive to take my business elsewhere.

I expect be able to use my OE LEAF pack (I expect to have ~16 total kWh remaining, by ~2020) to store my own daily PV production, to use both in my home, and in my BEV.

I won't need to size my PV system for winter conditions, since I expect to be able to buy kWh at a grid-connected charge site, transport this energy to my home in my BEV's battery pack, and download using V-to-H, as required.

I already own a ~225 gallon propane tank, and buying a propane generator will provide a (extremely inefficient, of course) backup energy storage capacity for supplying Kw to my home and vehicle, that doomsday preppers would envy.

Back on topic, since the Tesla Powerwall is so expensive per kWh of storage, and since the Tesla BEV sales model excludes V-to-H, just as it does V-to-G, I can't see how any Tesla product would ever be useful to me.

 

[WetEV]

If utilities are willing (or required) to continue to allow net metering, it seems that utility-scale storage would be more practical, whether huge batteries or something else, such as pumped storage. But if the utilities start pushing back against net metering then I think more of their customers will go off-grid.

Net metering doesn't pay for storage. Would need a lower rate for generated power than for stored power.

 

[AndyH]

If utilities are willing (or required) to continue to allow net metering, it seems that utility-scale storage would be more practical, whether huge batteries or something else, such as pumped storage. But if the utilities start pushing back against net metering then I think more of their customers will go off-grid.

Net metering doesn't pay for storage. Would need a lower rate for generated power than for stored power.

They shouldn't pay for storage today as the grid is a 'just in time' system. I don't think that grid operators should consider utility-scale storage as an excuse to soak the end user, though, as there are already plenty of ways for them to install a battery and make a standard rate of return without changing any part of their business model.

 

[LTLFTcomposite]

I don't get this theory of using the car battery as storage. Aside from needing every bit of capacity for commuting, the car(s) arrive back home on e-fumes needing to suckle just about the time the sun has gone down.
The Tesla brochure picture is even funnier, aside from the question of who keeps their garage that neat, what good is a 10kwh storage battery when you're charging an 85kwh car? Unless you're charging at work and bringing it home, the environmental equivalent of stealing office supplies.

 

[WetEV]

If utilities are willing (or required) to continue to allow net metering, it seems that utility-scale storage would be more practical, whether huge batteries or something else, such as pumped storage. But if the utilities start pushing back against net metering then I think more of their customers will go off-grid.

Net metering doesn't pay for storage. Would need a lower rate for generated power than for stored power.

They shouldn't pay for storage today as the grid is a 'just in time' system.

https://www.usbr.gov/projects/Powerplant.jsp?fac_Name=Mount+Elbert+Powerplant" onclick="window.open(this.href);return false;

Ignoring the relatively small amounts of storage on the grid today, there can be a cost to the grid associated with a large production of solar that in fairness should be charged to the producers of solar.

Take the town of Flatville, for example. Flatville has an exactly flat load, the town uses the same power every hour of every day, which was provided by fossil fuel power generation. One day, everyone in Flatville installs solar on net metering, and generates 100% of their energy use. The excess during the day is sold at lower wholesale rates, and the nighttime production is still provided by the existing generation equipment. The amount of fossil fuel burnt has declined, but the capital cost and maintenance of the generation system and the grid is the same, so the cost per kWh generated and delivered has also increased. Excess power sold makes up some of the gap, but now no one in Flatville has an electric bill to pay, but the system still has costs.

Net metering is a fair deal for everyone when the generation peak is during the day. Net metering is not a fair deal for the utility when the utility's generation peak is at night.

as there are already plenty of ways for them to install a battery and make a standard rate of return without changing any part of their business model.

Really.

Flatville decided to get rid of fossil fueled generation, and install batteries at night. Remember that with net metering, no one in town pays a dime. How does the business model work, again?

 

[mjblazin]

Increasingly utility, water, electricity, gas , costs will depend on the infrastructure to deliver the service and less on the material being delivered or removed. If you want to snap your fingers and access the various grids after however many periods on non-use, you have to bear those costs. Metering by time of day will change as behaviors change. If a sizable number start shifting usage to night, expect the rates to follow that behavior.

It is ok to be a margin player. You just have understand the risks you bear and not complain when you get crosswise with the market.

 

[TonyWilliams]

Actually, you could still charge the car with the built in charger (J1772) and use the CHAdeMO port without any charger... just a plug, some electronics to open and close the main contactor on the battery, and an inverter.

That's right, and it is exactly what Mitsubishi did with the iMiev PowerBox:

Mitsubishi PowerBox Press Release

IMO, this is the cheapest, simplest and safest way to provide AC power from an EV for emergency power or for portable power such as camping, etc.

Unfortunately, Nissan assured me that this unit would not work with the LEAF.

Why don't we build one that will work with the LEAF?

 

[AndyH]

Flatville decided to get rid of fossil fueled generation, and install batteries at night. Remember that with net metering, no one in town pays a dime. How does the business model work, again?

Utilities installing grid-level storage are reporting 'industry standard' rates of return - 10-12% - without charging PV producers for the battery. Similar math was done a number of years ago on large-scale battery projects in the US - like the Presidio, TX 'BOB' that's been covered on this forum. The US batteries were installed because it was much less expensive to provide a battery backup for an entire town than it was to run new power lines. As for the rest, this appears to be a rehash of your 'real costs' of renewables thread. I'll leave that back and forth there.

http://www.pv-tech.org/news/tesla_a...r_storage_system_price_down_60_hint_at_new_ut

In addition, the Tesla Energy range includes DemandLogic, the company’s commercial storage product which has already been available in some parts of the US since late 2013. Also announced was GridLogic, a micro-grid battery system.

SolarCity co-founder and CTO Peter Rive wrote on his company’s blog last night that the systems enable SolaCity to offer “fully-integrated and affordable solar battery backup systems for homes, businesses and utilities”.

With the residential batteries mostly offered for backup at present and DemandLogic offered to enable demand charge reduction for businesses, it will be interesting to see what further developments will come in terms of the batteries’ use and what kind of business models for both revenue and cost savings might be enabled in future.

 

[Slow1]

Ignoring the relatively small amounts of storage on the grid today, there can be a cost to the grid associated with a large production of solar that in fairness should be charged to the producers of solar.

Take the town of Flatville, for example. Flatville has an exactly flat load, the town uses the same power every hour of every day, which was provided by fossil fuel power generation. One day, everyone in Flatville installs solar on net metering, and generates 100% of their energy use. The excess during the day is sold at lower wholesale rates, and the nighttime production is still provided by the existing generation equipment. The amount of fossil fuel burnt has declined, but the capital cost and maintenance of the generation system and the grid is the same, so the cost per kWh generated and delivered has also increased. Excess power sold makes up some of the gap, but now no one in Flatville has an electric bill to pay, but the system still has costs.

Net metering is a fair deal for everyone when the generation peak is during the day. Net metering is not a fair deal for the utility when the utility's generation peak is at night.

For the point of discussion your model is good but realities are of course more complex with multiple peak demand times etc. In your town of flatville, the solution simply is to use TOU billing and adjust the amounts paid/charged to adjust for the value of the energy in each time period. When FPUC (flatville public utility company) is selling on the wholesale network they should not be paying more than that for the power. During peak demand times, charge more for the power. Balance will come.

Flatville decided to get rid of fossil fueled generation, and install batteries at night. Remember that with net metering, no one in town pays a dime. How does the business model work, again?

With TOU billing (both directions) and a basic connect fee, it should be possible to collect enough to pay for the infrastructure (primarily connection fee) and the generation/storage. IF FPUC can more efficiently either store or generate on demand than individuals can do the same they stay in business, if they cannot the the optimum solution would be for individuals to do it themselves, I expect that it SHOULD be possible to do this more efficiently on a larger scale - if nothing else, the individual peaks of production/demand should on average offset each other at least to some degree - i.e. less storage required for the whole town than the sum of all individual users if they size to handle peak demands.

 

[edatoakrun]

="LTLFTcomposite" I don't get this theory of using the car battery as storage....

Why would you not want your BEV to have this capability?

I expect that in the near future every BEV battery will be capable of supplying the grid through dual-purpose G-to-V and V-to-G devices, allowing BEVs to rid themselves of the extra cost and complexity of on-board chargers, and allowing every battery owner (whether their pack is on wheels, or not) to participate in the daily electricity market.

="LTLFTcomposite"....Aside from needing every bit of capacity for commuting, the car(s) arrive back home on e-fumes needing to suckle just about the time the sun has gone down....

Very few ~20 kWh need the entire capacity to complete daily driving needs, not to mention those BEVs with even larger capacity packs.

Remember also, that the grid nationwide will probably soon see what California does today, two peaks in conventional kWh demand daily, morning and evening, on either side of the peak in solar production during the mid-day.

So, even if you have only ~20 kWh available from your pack, and need nearly 20 kWh for your daily commute, you could still drive to work on a full charge, discharge during the morning peak, recharge midday, and discharge again during the evening peak after you get home, before recharging to full again during the off peak hours at night.

And you could pocket a nice piece of change every day, as long as TOU rates have significant price variations.

="LTLFTcomposite"...The Tesla brochure picture is even funnier, aside from the question of who keeps their garage that neat, what good is a 10kwh storage battery when you're charging an 85kwh car?....

Not much, obviously.

But I think two more important questions are:

Why would you want to put 85 kWh in a BEV in the first place, When ~20-30 kWh with a range-extending system (BEVx) is much less expensive, gives you longer driving range, and produces far less adverse environmental consequences?

And (especially with a larger battery BEVs) why would you want to neuter their V-to-G capability?

 

[evnow]

It was Steve Levine, the author of the Powerhouse.

He is a journalist - not a battery expert.

Previously, Steve was a foreign correspondent for eighteen years in the former Soviet Union, Pakistan and the Philippines, running a bureau for The Wall Street Journal, and before that writing for The New York Times, the Financial Times and Newsweek.

I'm fairly sure a lot of battery improvements are yet to be made. I don't think we have hit a wall yet.

 

[WetEV]

For the point of discussion your model is good but realities are of course more complex with multiple peak demand times etc. In your town of flatville, the solution simply is to use TOU billing and adjust the amounts paid/charged to adjust for the value of the energy in each time period. When FPUC (flatville public utility company) is selling on the wholesale network they should not be paying more than that for the power. During peak demand times, charge more for the power. Balance will come.

With TOU billing (both directions) and a basic connect fee, it should be possible to collect enough to pay for the infrastructure (primarily connection fee) and the generation/storage. IF FPUC can more efficiently either store or generate on demand than individuals can do the same they stay in business, if they cannot the the optimum solution would be for individuals to do it themselves, I expect that it SHOULD be possible to do this more efficiently on a larger scale - if nothing else, the individual peaks of production/demand should on average offset each other at least to some degree - i.e. less storage required for the whole town than the sum of all individual users if they size to handle peak demands.

Yes, a TOU billing is one of many solutions to this problem, but TOU billing is not net metering.

 

[mjblazin]

It was Steve Levine, the author of the Powerhouse.

He is a journalist - not a battery expert.

Previously, Steve was a foreign correspondent for eighteen years in the former Soviet Union, Pakistan and the Philippines, running a bureau for The Wall Street Journal, and before that writing for The New York Times, the Financial Times and Newsweek.

I'm fairly sure a lot of battery improvements are yet to be made. I don't think we have hit a wall yet.

An expert is also someone that is acquainted with the current state of work in a an area and what problems/solutions exist in active development. He or she does not have be a flange head beating on metal.

A wall is a point that you do not yet know how you will get over it. Until someone invents a ladder, it is a wall. The truth is a lot of smart people in this area have an idea they need a ladder, but are not close to understanding what goes into a ladder. The prescription now is to work out, build your legs, get better shoes and be able to jump a little bit higher. Doing leg lifts will only get you so far.

 

[BrockWI]

I am not sure about other utilities, but here we pay $21.90 a month to have a meter and then pay for what we use. If you have a grid tied system you get a second meter with the $21.90 charge and then pay a $9 fee to be able to sell. I am not saying I am against this way of covering their cost's, but this is half the reason I have a downstream only PV setup with batteries. The other half is the ability to keep powering most loads with or without the grid. We are on time of use and I simple disconnect from the grid during peak times and let the solar do the work.

 

[evnow]

An expert is also someone that is acquainted with the current state of work in a an area and what problems/solutions exist in active development. He or she does not have be a flange head beating on metal.

How do you know he is - because he was on TV and wrote a book ?

A wall is a point that you do not yet know how you will get over it. Until someone invents a ladder, it is a wall. The truth is a lot of smart people in this area have an idea they need a ladder, but are not close to understanding what goes into a ladder. The prescription now is to work out, build your legs, get better shoes and be able to jump a little bit higher. Doing leg lifts will only get you so far.

You are making a lot of assertions here based on ... what ?

Battery is big business. Commercial state of the art battery R&D is not disclosed easily to anyone ...