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Your Future Home Might Be Powered By Car Batteries (bloomberg.com)
Increasingly utilities and automakers are wondering if they could use the batteries inside electric cars as storage for the entire public power grid. An anonymous reader shares a report: The idea, known as "vehicle-to-grid," is to someday have millions of drivers become mini electricity traders, charging up when rates are cheap and pumping energy back into the grid during peak hours or when the sun simply isn't shining. If it works -- and it's a big if -- renewable energy could get much cheaper and more widely used. "We really, really need storage in order to make better use of wind and solar power, and electric cars could provide it," said Daniel Brenden, an analyst who studies the electricity market at BMI Research in London. "The potential is so huge." Today, fewer than one percent of the world's vehicles are electric, but by 2040 more than half of all new cars will run on the same juice as televisions, computers and hair dryers, according to estimates by Bloomberg New Energy Finance. Once cars and everything else are fed from the same source, they can share the same plumbing.
I thought they made a car specifically for this use pattern. And they took away the car and called what was left the "Powerwall". Sure, you stick it to a wall rather than ambulate it all over town, but I think it works out just fine.
"Everybody's naked underneath" -- The Doctor
This is silly. Battery technology hasn't matured so workarounds like this aren't really solving any problems. By the time there was widespread adoption of this (my guess 5-10 years) technology will have moved on and the issues we think are a big deal will be different.
We're still far away from batteries reaching their peak performance. We develop more powerful batteries (ok, dear nitpickers, accumulators) that can store more power per kilogram of battery at a rather fast pace, and I guess discussing today what we'll do with them in 10 or 20 years when "everyone" has a battery powered car (if it ever gets to that, anyway, and the electric car isn't replaced by something completely different in the meantime) is a bit like gazing into the crystal ball.
Let's first of all finish inventing the storage before we ponder spending the energy.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
"The potential is so huge."
Tesla battery pack voltage potential is around 400 V, dangerous for human life, but not exactly "huge".
The average age of a car on the road in the USA is 11.5 years. Personally, I drive a 1998. If only 50% of new cars in 2040 will be electric, then we're looking at sometime between 2050 and 2060 for a slight majority of cars on the road to be electric. So this plan had better work with a fairly small percentage of cars being electric, or it'll come way too late to do any good.
A better use of electric cars may be simply using their depleted otherwise-worthless batteries as part of the grid. That way you don't have to convince people to let their battery be worn down, either -- getting people to allow their car battery to be used to balance the grid will really require that they be getting free replacement batteries, because it can't be good for battery longevity.
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I love markets, but so often, clever people try to create markets for their products, rather than solving people's real problems.
It turns into yet another, suck the life out of the little guy, for the profit of some new venture.
The bottom line in business should be that what you are doing is genuinely worthwhile and creates genuine value for humanity.
And people need the integrity to answer for themselves honestly whether what they are doing it of genuine value, or merely profiting off whatever "wonderful world saving" thing is fashionable.
It is stuff like this which reminds me we are in The Bad Place.
I can't believe people still think this is a good idea. These people still don't seem to have spotted that the reason you plug your car in is so that it's fully charged when you want to go somewhere. So in ten years' time, you'll hear this conversation:
"Quick! My waters have broken! Get me to the hospital!"
"Wait, no, sorry, can't go, it's been cloudy all week and the grid's left our car with only 30 miles range. Can you hold it for an hour until it's charged enough?"
Slashdot - News for Nerds, Stuff that Matters, in ISO-8859-1 Has just realised that beta makes this signature redundant
In some country, petrol IS NOT the thing stations profit the most.
At least in several places in Europe, stations profit the most from their shops (selling snacks and other small useful item. At a high price than in the city, but more convenient or in an emergency, as they are open 24h and on your way on the highway) and their cafe (taking breaks is heavily recommended by massive campaign and even legally required in some driver professions)
In fact several chain of stations are actually owned by chain stores.
The petrol is mostly use as a way to attract people to the shops/cafes.
As soon as electrical cars became a thing some stations started to install charging station as a way to attract even more customer to the shops and cafes.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Like through a series of tubes?
The Powerwall costs extra money, but you will already have your car battery, so there is no additional capital cost other than an inverter.
Not quite. You also have to factor in the cost of the additional cycles on the battery pack, the additional warranty and maintenance costs that may result, the depreciation on the vehicle from this additional use, and perhaps a few others I'm not thinking of before I've had my morning caffeine. Doesn't make using the car battery a bad idea but one should have a full accounting of all the costs. I think depreciation likely would be the biggest cost since inverters probably wouldn't be super expensive once they are produced at scale. I could easily see the added depreciation being a few thousand dollars though you obviously wouldn't be hit with that until you sell the vehicle.
Personally I see car batteries as more of an emergency standby solution than a routine use. Not much use for powering the home if you have to take the car to work. Could be a nice little extra layer of security for power outages or to manage energy costs and usage though.
the point would be to have both home battery and EV. the battery can service the home and the EV battery be available to supply the grid if needed
"The hands that help are better far than lips that pray." - Robert Ingersoll (1833-1899)
they wouldn't discharge the whole battery. the discharge will be shared by multiple EVs and there will be a configurable setting to say just how much charge they can take. And they will only take when the power usage spikes so from midnight on they probably won;t be taking from the EVs
"The hands that help are better far than lips that pray." - Robert Ingersoll (1833-1899)
its a lot more than that. https://en.wikipedia.org/wiki/... its also about creating multiple micogrids to manage a 2 way distribution of power
"The hands that help are better far than lips that pray." - Robert Ingersoll (1833-1899)
Transportation accounts for about 70% as much energy consumption as electricity. If you convert all those ICE cars into EVs, the electric rates won't be cheap during the night when they're charging. Overnight will become the new peak consumption hours, when electricity is most expensive.
I recognize that in terms of how things are priced today that this seems like a great idea. However, the capacity of batteries is going to greatly increase while the price of them is going to drop like a rock. Effectively, things will get to the point where people would ask, "wait, why would you even do that?" leaving off the implication that batteries are dirt cheap.
Solar and battery are going to power most every home in the future and might even have power left over to charge your car because it's going to be extremely cost effective.
Anons need not reply. Questions end with a question mark.
Or from a "bring your own device" policy, it will rapidly switch to a "bring your own battery" policy to further lower infrastructure costs.
(Disclaimer: EV owner, researcher in relevant field, and I was once asked to evaluate a research project on V2G in an European country)
The idea is interesting, and may well have an impact in countries with a lot of non-controllable power (wind, sun, but to a degree nuclear and other baseloads too), if price oscillations are large enough. The article mentions a potential of USD 40 a month, which is just above a buck a day. Would you risk not having enough charge in your car to get home for such a pittance?
More importantly, there is no mention of battery wear. Batteries are much more expensive than the energy they store through their lifetime. Teslas have actually a very limited lifetime of about 500 cycles (since the batteries are large, there is no need for more lifetime—it's actually smart to use short-lived, cheaper NCA batteries as Tesla does), which means that, if you assume USD 200 / kWh by 2030, each kWh will cost 40 cents only in battery depreciation: that's a lot more than what the energy costs, and will likely more than offset those 40 USD a month. (Yes, there are longer-lived batteries; they are also more expensive) (Yes, battery wear is not just a matter of cycling, it's also storing at high voltage, rate of charge/discharge at which temperature, and lots of other things)
V2G is very interesting for grid companies as a solution to their energy storage problems, but they seem to intend to exploit the lack of consumer understanding of EV cost dynamics: the real cost of a kWh is the battery wear, not the actual energy. There is a reason why these companies are not buying the batteries directly.
I believe V2G has more potential in "private grid" applications: e.g. if you have a cabin in the woods with no option of grid connection, you could drive to it with you EV and power it from your batteries while you are there (a home uses a lot less power than a car); or you could transfer some charge to a vehicle that ran out of it on the road (actually the Toyota Mirai has a similar feature, a ChaDeMo outlet).
Victims of 9/11: <3000. Traffic in the US: >30,000/y
Supercapacitors in cars instead of or in addition to batteries could be the hot setup:
https://www.engadget.com/2018/...
The thing is, if your car is giving up its charge to the grid, and you suddenly want to go somewhere, that's not ideal. But if the car has a supercapcitor that can charge in 10 minutes, then it works much better. The power wall for storing charge could come into play by charging the car quickly, since drawing that kind of amperage through the grid wouldn't be possible - 200 amp service at 240 volts is only 48 KwH an hour, so with the best electric car mileage currently being around 4 miles per KwH, that's about 192 miles of electrical energy per hour available to charge the car's battery. Fine if you have an hour to kill before you leave, but if you want to go right now, you can't. But a battery charging a supercapacitor, especially several batteries in parallel, could charge in several minutes - just set it to charge 10 minutes or so before you leave, and it's done when you're ready.
So this could be the storage that the grid really needs to go renewable.
Problems? If there's a disaster on the way, such as a hurricane, everyone is going to want to be leaving at once. Most home batteries will be supplying current to charge cars, not supply the grid. If the weather is bad, which it ought to be with a hurricane on the way, the solar isn't helping, and if the wind is too fast for wind turbines, does the whole thing fail at the worst possible time? Maybe.
"Of course with electric cars, no more "road trip" vacations or driving the kids off to college because it can only go 100 to 200 miles on a charge and then it takes 8 hours to recharge."
Maybe not:
https://www.engadget.com/2018/...
And if it won't do "road trip", I'm not going to buy it, so someone needs to figure out road trip with or without a supercapacitor. 1st leg of my vacation last month was >800 miles.
We're still far away from batteries reaching their peak performance.
Probably true though I think we're pretty close to the limit for Li-Ion batteries. The question is how soon can the next battery technology get to market.
We develop more powerful batteries (ok, dear nitpickers, accumulators) that can store more power per kilogram of battery at a rather fast pace,
Define "fast pace". Energy density of batteries has been increasing at something like 5-8% per year. Nice but that means it takes 10-15 years to double. Not exactly Moore's law though with a long term perspective I suppose that's pretty decent progress. I don't know that I'd call it fast paced but it's good enough to be optimistic about the future of batteries for powering homes and transportation.
Let's first of all finish inventing the storage before we ponder spending the energy.
Classic engineer thinking of trying to get everything perfect before first use. I think we are all guilty of that now and then. While I respect the intent that isn't really practical in the real world. Don't make perfect the enemy of good. One needs to ponder use cases along side development pathways.
It was about 14 miles to work, and 14 miles back, and I was not about to waste an hour or more each way just to arrive all grody / sweaty both at work and at home for as long as I could do that, which would be until I got run over on some of the more dangerous roads I know of. Hilly, curvy, narrow, a bicyclist has a death wish if he rides those roads. And of course I retired 6 years ago at 64 years of age, and have doubts about really being able to pedal that far anyway every day even if the roads were safe.
Right now, energy driven cars seem to be the future, but we don't even know what kind of energy storage is the best.
Best is what works and has the best combination of economic utility and environmental friendliness. It seems pretty clear that battery powered EVs are the most credible option moving forward. Lots of advantages not the least of which is that the fuel source is abstracted from the vehicle and that there is existing infrastructure for refueling. You can power a battery powered EV with gasoline or coal or nuclear or wind or solar or anything else you can make into electricity. The value of that abstraction of power sources almost cannot be overstated. Plus the fact that you don't have to build the entire fueling infrastructure from scratch is equally huge in value. Even better you can have hybrids which allow use of both electric and petrol fueling infrastructures.
Other potential options like hydrogen fuel cells have too many obstacles to really be likely to make headway in the market. It would take a miraculous technology breakthrough for anything other than battery powered EVs/hybrids to really have any chance at success.
When it comes to energy density, the ICE and petrol are still superior to other forms on a pure power-per-kg level.
Not once you include the weight of the engine and power train and consider efficiency. You're comparing apples to oranges. If it were that simple electric vehicles like the Tesla would lose every drag race they entered. You have to consider the weight of all components involved in turning that fuel source into power and how efficiently it does that task. On that measure ICE doesn't look nearly so pretty.
We should first of all figure out how to replace this, and what to replace that with, before we start planning a whole house around it only to discover that eventually we'll start over from scratch.
No. Absolutely not. The only way to figure out what works is to try things in the market. It's going to be a little messy but that's not a bad thing. The good thing about battery powered EVs is that it doesn't actually matter what type of battery is in the vehicle. You can upgrade those as technology permits because it doesn't require any adjustments to the refueling infrastructure. If we get a battery tomorrow with double the energy density the only effect is that cars can go farther. Same with batteries to power a house.
There is only one way to power your cellphone, with a rechargeable battery. You certainly won't put any kind of fuel cell into it, you won't power it with gas or an ICE.
Actually you might power your cell phone with gas, just not directly. The gas is turned into electricity at the power station instead of in the device. That is the advantage of batteries. You can use the most practical fuel source available. It becomes like using money instead of bartering. The fuel source gets abstracted from the device.
A house or even car is kinda different in that aspect.
A car is no different than a cell phone regarding power versus weight. It's bigger but there still is a power vs weight vs space budget to deal with. Any mobile device regardless of size does not escape this reality.
Homes don't have to care so much about weight obviously so that's a bit different. There still can be a space budget but since the device is static you don't have to worry about weight so much.
A lot of pure EVs store significantly more power than the average home uses in a day so there's a good chance it can be used to store renewable energy. Even if people can't get renewable power, they're valuable for levelling power use. Part of what keeps electricity costs high is that our power use swings wildly during the day so power systems need to be designed to generate more power than will ever be used.
Also most EV's use the much more reliable LIthium-Iron-Phosphate class batteries (https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery) which wear out at a much slower rate than most lithiums and rarely if ever catch on fire. Tesla I believe doesn't use these more reliable batteries but the trade-off is the ability to pack more power in a smaller space / weight which is why they have some of the smallest batteries for their incredible capacity on the market.
For what it is worth...I was in India a while back in summer. Almost every household there had this thing called Inverter hooked up right at the mains. Basically a step up/down transformer hooked up to a truck battery (car battery wasn't considered powerful enough). With daily power cuts, the inverter kicks in to keep basic light and essential services (Fridge, freezer etc.) running.
There are variety of reasons why people there are doing this but as a concept it is already being done, when about half the city has a power cut, yet most of them are running on battery power. I must add, it is was at the time/place considered illegal to have these devices cause they put extra load on the grid when they are on charge.
I am at loss with words...
Get solar panels with a battery buffer, rely on the grid as little as possible. Solar panels not enough for your "needs"? Reduce your consumption, switch to power-saving alternatives. It's good for everyone.
Eat the rich.
Even as battery prices have fallen, it still costs much more to store and recover a kilowatt-hour of power from a battery, than to produce it in the first place. The battery is still by far the most expensive component of an EV, and (since there are so few moving parts) the first to wear out. To make it cost-effective for EV owners to wear out their batteries by renting them for storage, they would have to be paid triple or quadruple standard power rates, at least. But if EV sales really do take off as predicted, a more likely source of power storage will be a surplus of partially degraded used EV batteries, with too low capacity for on-road use but still perfectly adequate for stationary storage, where the energy/weight ratio is less critical.
So they're pumping electrically-charged juice through the plumbing now? Why are they not using the same pipes as the internet?!
#DeleteFacebook
Regardless, I'm not keen on the idea, and since in home use, weight is not a factor, so the lead acid family of batteries would function very well for home storage
The only big advantage of lead acid batteries over Li-Ion in most use cases is their price tag which is quite a lot lower than Li-Ion. But lead acid batteries are worse on energy density, can require more maintenance, usually have fewer fewer cycles, are more temperature sensitive, worse capacity vs discharge rate, are less environmentally friendly, etc. There are plenty of use cases where lead acid is a fine choice but Li-Ion is the clear performance winner in most use cases. Provided of course the cost meets your budget.
My current home has been powered by batteries for ten years
Yeah, there seems to be a battery breakthrough story every couple weeks. I bit really hard on the 10X boost over lithium that was described as "nanowire batteries" in I think Dec 2007 issue of Spectrum, but the scientists were scooped up by offers from I think it was a Saudi University where the thing was probably suppressed for what it would do to the Arab oil business.
You could "fill up" your car in one location, drive home, and pump that power in to your local grid. If the local prices were high enough it could be affordable. You could get some sort of "energy truckers", hauling batteries across territory from grid to grid.
That would make things interesting, though I can't imagine it would be terribly efficient. It would encourage companies and governments not to build out proper electrical grids.
I'm a good cook. I'm a fantastic eater. - Steven Brust
Hell, whole towns could do this. Why bother setting up energy distribution if you can just make people drive it in.
Why not expand this to water? Make people haul it in with no support from the government. Works for Flint, right?
I'm a good cook. I'm a fantastic eater. - Steven Brust
" -- and it's a big if -- "
Ah, Bloomberg "news", throwing shade on the idea that many cars could ever be electric. Mad, mad! I tell you! Gods and Monsters!
Of course the idea will work. It can't not work. There ain't no "if" involved. Electric cars will lower our power bills, aid grid overload, and walk the dogs while powerwashing the sidewalks. Blackouts will lose their terror all over the world. The upsides of electric cars are now obvious and I can't wait for a VW Beetle cheapie version for the Rest of Us.
While you may think that it is wonderful to live in your tiny hovel in a mild climate region
It's probably something like 6 kWh overnight for the whole three-story building with 200 square meters of residential area.
My modest home uses an average of 90kWh per day. That's an annual average.
I'll shed a tear for you. Meanwhile, maybe in the years to come, your people will learn to build properly?
Commercial usage is the killer. My small business uses over 3,000kWh per day and it is not a major consumer. I can't even imaging how much some of the big factories or shopping malls must use.
True, but surely that is outside of the scope of TFA. Unless you live IN the business, of course.
Ezekiel 23:20
I can't come into work today. It was a hot night and the AC was on constantly. My car batteries are dead.
This is NOT what power companies want. Your local power company, who you send your bill to, probably has zero say in the actual generation of power. They buy power from the grid (think of the guys in NY mining bitcoin) and the quantity of watts they purchase has been agreed upon far in advance. Otherwise how would the large plants know how to schedule for demand? And vice versa; when home users decide willy-nilly to "sell back" and there is too much power available, what happens then? You don't just spin down your house sized steam turbines when home users with a car or batteries or solar start pushing back. Home users do not get the same treatment as a large industrial users either. That means your home power is never cheaper at 2:00AM like it might be for a big Aluminum smelter. This whole premise is crap.
The assumption here is that you'll have solar panels that generate enough power to cover a big chunk of your electricity needs, and that you're using a combination of the grid and your car battery to account for differences in supply and demand, since you'll only get max solar output for a few hours a day.
In your specific case, have you looked into getting a big propane tank and periodic deliveries? That's the normal solution for northerly climes where piped natural gas isn't available. It would be a lot cheaper than electric heat (though possibly not as green, depending on how your electricity is generated).
An even better option for you would be a ground loop. If you're out in the boonies you probably have enough land that you can go shallow and broad, which is cheaper. Then your heat pump can move ~50F subterranean temperatures into your house. Much shallower gradient than whatever that air temperature you're pumping from is. You'd still be using electricity, but it would be dramatically more efficient.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
Energy shaping doesn't only need pumped water up an incline (hydro) for power generation, it can also use batteries, or even biofuel or split water into H2 and O2.
When you combine the jagged shapes of the wind potential in many regions with the solar potential in many regions and compare it to actual demand, you find it smooths into a nice curve that closely matches actual demand, and you can start using a combination of batteries and intelligent power systems that only perform tasks during high power availability.
-- Tigger warning: This post may contain tiggers! --
V2G (Vehicle-to-Grid) is not new. It's been hyped for years and will continue to be hyped because it helps (1) sell EVs and (2) rooftop solar. The problem is that the communication standard (ISO 15118) just to get vehicles to communicate with EV supply equipment isn't even adopted by the majority of big EV charger companies. It's adopted in "roadmap", but cars cannot yet speak to the grid. Moreover, the entire goal of V2G is being oversold to employers who are being told, "Hey, if there's a power issue, you can just tap all the EVs your employees have plugged in," to which all the employees will eventually respond, "Like Hell you will. I need that juice to drive home!"
Lastly, let's just do what we all know we should do: spend excess energy on distilling water and then splitting it into oxygen and hydrogen (hydrolyzer). Store that hydrogen as a battery (fuel cell) or sell off the excess. No need to mind rare earth metals and deal with their eventual disposal. Just stay clean in the process.
What idiot mixes plumbing with electricity?
Try living somewhere where it gets REALLY cold in the winter
The things you describe affect only a very small percentage of Earth's population, though. This means that it may suck for you (I still think your insulation cold be improved, though) but for a massive majority of people, 100 kWh gets them through a week at least rather than through a day.
Ezekiel 23:20
Through kinetic recycling, hydrogen engines and other techs that we're not privy to. The car becomes the power plant.
Sure hope it's not like my car and always starts on cold mornings. Then too, be just my luck someone would leave the headlights on all night and drain the battery.
In Smokey and the bandit 4. Trucks full of molten salt will bring bootleg energy into Ca and sell it on the black market.
Nullius in verba
There are people who have already done this. For example: http://www.mynissanleaf.com/vi...
The 12V bus on the vehicle provides ample power to run small electronics, and even some larger ones. Depending on the model, it is possible to get 100A - 200A current thru an inverter, which will give up 20A over 120V, allowing 2kW continuous operation.
Of course there are some caveats. First the battery is not designed for this kind of load, and it will decrease its total lifespan. Also you need to make sure the parts used are high quality, and able to handle the currents mentioned. (i.e.: very thick cabling, with actual copper in them, instead of aluminum mixes). Also you'd want to watch over the contraption, and of course have circuit breakers in case something goes wrong. Everything needs to be connected directly to the internal terminals, and the car should be in "idle" mode (i.e.: main battery is enabled, not just the 12V lead acid one).
But it will allow you to run your fridge and some lights when the power goes out, even for very extended periods (1-2 days is possible). You can also use this when camping.
Used correctly, lead acid batteries have far longer lifetimes, and can do far more cycles than lithium ion.
No they do not. Quite the opposite actually. It's not even close.
The average USA house hold only uses 30KWH per day. Most of the marketed electric cars could completely run a house for 2-3 days
While true as a general proposition (one has to be careful talking about averages), it's not clear that using your EV to power your house is a good idea as a routine matter. A lot of the residual value of the car will reside in the number of charge cycles the battery pack experiences. I could see doing that from time to time to help with emergencies or to smooth usage during the occasional peak time. But I think it would be a bad idea to routinely use your EV battery to power your home. It's not really designed for that purpose even if it might work acceptably well. I think something like Tesla's power wall makes a lot more sense for that purpose AND it does not require your car to be present in the home.
Most of the warranties are for a full battery cycle every day for 10 years, and even then the battery will still be around 80% capacity.
I can almost guarantee you those warranties do not cover powering your house. I'd be surprised in fact if they didn't specifically exclude it. That said, Elon is crazy enough to possibly do it anyway.
The cost to produce a li-ion battery has gone down 25% between 2016 and 2017. They're getting cheap.
They are getting cheapER. They aren't cheap. Not yet anyway. Good cause for optimism however.
That's what a friend who lived off-grid used. Shed full of marine batteries. Cheap, durable, and easy to replace.
I'm sure it worked just fine and was reasonably economical at the time. But times are changing and so is battery technology.
About every 3 months he'd test all the batteries, replace any that were wearing out, close the door, and maintenance was done.
Which is clear evidence that they are not suitable for use by the General Public. I cannot imagine most people checking a shed of batteries on a routine basis even if they wanted to. They want something they can install and more or less forget about and which self monitors. Your friend is obviously a diligent person and technically inclined but what he did would be utterly incomprehensible to your canonical technologically impaired grandparent.
Compared to a power wall, that was far cheaper, stored vastly more energy, and provided higher power draw. The only thing it didn't have was looks.
Cheaper I would believe. "Stored vastly more energy"? Maybe per dollar but that is entirely a function of how many batteries you have. They definitely do NOT store more energy per battery than Li-Ion. And of course he would have to replace the lead acid batteries more frequently. Your comment about power draw is equally nonsensical. Li-Ion is demonstrably better for most high draw applications.
There is nothing about marine lead acid batteries that provide more energy storage or greater power draw. I have no idea where you drew those conclusions but that isn't what the evidence shows. Lead acid batteries (marine or otherwise) are substantially less efficient, have fewer charge cycles, are much bulkier and heavier per unit of power, etc. The ONLY big advantage that lead acid batteries have is price. That's an important advantage but it's one that will go away in the near future.
I'm not certain why some think that Marine or deep discharge batteries are not lead-acid batteries, but their main drawback is that they are so darn heavy. But they are inexpensive, and dead easy to recycle.
Their weight is among their smaller disadvantages though for mobile applications that is a killer problem. Compared to Li-Ion they have fewer charge cycles, worse charging and draw characteristics, more temperature sensitivity, are less efficient, have worse power and energy density, etc. Lithium batteries can be recycled just fine too. From a performance standpoint Li-Ion wins in most use cases if you ignore price. There are some corner cases where lead acid comes out on top but most of the time it's really no contest.
Lead acid batteries (marine or otherwise) have two primary advantages. They are cheap and they are readily available. And both of those advantages are rapidly disappearing because the price of Li-Ion is falling fast and as they capture market share the cost of lead acid will at some point start to rise or at least bottom out. I would expect cost parity within the next 10-15 years at which point the only reason to use lead acid batteries is for certain corner cases where Li-Ion might be problematic.
Do you really care how much the "power plant" of your home weighs?
A little but mostly I care how much space it takes up and bigger usually correlates strongly with heavier. A lot of people don't have huge homes and even those that do probably have better uses for the space than needlessly large and heavy mechanicals and power systems. I'd prefer a compact Li-Ion battery bank to a bulky and heavy lead acid version even if the performance was otherwise identical.
And that was what I was basing my comment on, but failed to clearly state. And as long as that's true, they're still a better investment.
Better is subjective and depends on the person doing the buying and what they hope to accomplish. If money isn't the obstacle then the better investment could easily be a higher performing Li-Ion system. They aren't better if the potential buyer opts out completely because it's too much hassle or too much expense. Right now that is the case no matter what battery technology you are talking about. It's both too expensive and too much bother for any type of battery for most people. The good news is that both problems are being resolved. I expect we will see a lot of companies making something similar to the Tesla Power Wall with a huge boost in ease of use and maintenance. Solar and wind systems are getting easier to manage and cheaper all the time. It's going to take a few decades but I like where things seem to be headed.
Then they're not ready to live off the grid.
People who live off the grid are fringe individuals who think it is an interesting lifestyle choice. Not being judgemental - I think it's cool - but it's an unusual perspective on life. That describes a fraction of a fraction of the people who might buy a battery system for their home even among those who have the technical chops. But frankly most of the benefits of being off grid can be realized without actually going off grid completely. It doesn't have to be an all or nothing proposition. Putting a battery bank in your typical suburban home with some solar panel can achieve a lot of the same benefits. It will be really interesting if/when it gets to the point where a large fraction of homes are generating much of their own power.
You seem to think that being energy-independent is a carefree, easy way to life. It's not. Well, not unless you have piles of money to throw at doing that.
Never said anything about it being easy. But there is no technical reason that it cannot be made so. The main obstacle really is price and that is being worked on by a lot of very serious companies, Tesla not the least among them. Early adopters always have to pay a lot more.
I'd be more than happy to install a solar roof, have a battery pack, and an EV. I already have a well, and could run my heating off of propane if I needed to. I've already done some of that myself (some solar and battery) with more to come. I think every roof should have solar panels on it and every house should have a battery system but I recognize this will take time and a lot of technology development to realize. I don't really see a need to go completely off grid but I think it makes a ton of sense to be able to generate most of my own power without needing the grid 24/7.
you have to wire your car batteries through the net and pay for using it or you're a terrorist tax evader
Free speech was meant to be free for all... how can anyone grow up in a nanny state ?
one has to be careful talking about averages
Very much so. I was using my limited experience to make my decision of using an average in discussion. In my case, I only use about 500KWH/m during the Summer, and I live in a duplex with almost no insulation and the AC unit is from the 90s, pre energy star. My AC runs constantly during the Summer. I also have several computers that run 24/7, and a TV or two that run 24/7 for the pets because of anxiety, better than drugs. Someone with a modern AC unit and decent insulation should use less power than I do and I use about 1/2 the average. I am not sure if the average includes all industrial usage averaged over the capita or the "average" person likes to have a chandelier with incandescent bulbs.