I’m looking into this as something I might add to our home in a couple years:
Right now, I think the technology is definitely doable, but I want to see more data on these batteries. I know I could do this with an off grid solar system and a large bank of bus batteries and 15KW inverter, but that is pricey and would take up a lot of space in the garage.
Take Care,
Buzz
So these are compelling until you look past the marketing hype these glowing articles really are. Dig a bit deeper and you’ll see that the listed price is merely the unit cost- installation is roughly equal to the Powerwall itself, assuming your house does not have wiring issues that need rectification before Elon’s wonderwall graces you eco-chic home. Wanna power your vital loads? Unless you already have a separate critical load panel, you’ll need to pony up that expense, too. [deleted this part because I quoted a sales rep who has no engineering back ground. I fact checked those claims with an electrical engineer who said BS. Also realized I can’t do math without a calculator]. I looked into this thing the three days after it was announced world-wide, having just walked into the house during a random power outage. With $$$ of perishables in hand, and a fridge full of milk my wife pumped for the baby, I thought I found the answer to many late nights searching for economical solutions to power redundancy, if not independence from the grid. Oh, btw, if you are a low power consumer/already efficient house hold (we average 180kwh./month in my 2000sft home) the eco-hipsters at SolarCity will scoff and claim that you are a waste of their time and money. Yes, that is exactly what they told me when I read my utility statement to them. Silly me- I believed Elon via SolarCity was trying to save the world.
ETA: Just spoke with an EE who is a PV installer. Even though he is signed up to be a dealer when the PowerWall is available, there are no engineering specs available. To summarize our conversation, Tesla is putting the advertising cart way out in front of the horse.
Yes, my above is cynical and bitter, perhaps, but just think of it like this: the Powerwall is in Gen1 of its release. Nascent technology, not really known/supported…give it a few years, let the early adopters find the bugs, and give the engineers time to rectify it… I’m sure the Powerwall (and it’s less advertised, but perhaps more mature competitors) will be more mainstream. There’s one particular product I cannot recall the name of, but it is the same thing- a wall mounted, low profile all-in-one battery back up that (I think) is no less capacity nor any more expensive. To my knowledge it has been around for a while (maybe not in the US market, so maybe that’s one reason the Powerwall seems so uber-cool- it’s new to us!). If I have it listed in my notes I will post here.
ETA: here’s that alternate modular battery system: http://jlmenergyinc.com/energizr
I subscribed to HomePower for years. You can go off grid, but it calls for a level of dedication akin to a religious order. As a guy focused on minimizing utility use, we are the best prepared to make the plunge. The problem is the economics still do not work… My last estimated payoff period was 27 years, nearly the length of a mortgage.
Oh, one item comes to mind is the SunnyBoy system. I don’t know much about it (the PV guy was pushing this thing hard til I told him NO!! for the fourth time) but it is an integrated battery/PV back up or small-scale off-grid system. You’ll need to manually cycle the power to/from battery, so if you want an automatic system prepare to shell out $$$ for a genset/ATS, but if you want a simple emergency battery back up this might be it.
On the sub, we as electricians had to enforce this concept with an iron fist. Vital loads were truly ship’s safety- and we would strip loads (cut power to entire sections of the ship) in order to accomplish this. Learn to do more with less- being a miser with power, water, food, money, etc…goes a long way when you want to be self-sufficient. Personal comfort is a state of mind…
The 21st Century equivalent of the traveling salesman. The only reason that clown is still in business is because of taxpayer $$.
Thought you were talking about His Eminence and Solyndra…then I reread top to bottom 
Could have been just as easily…They’re all in it together, taking our money for the Gubment picked winners and campaign contributors. Tesla has yet to turn a profit and it isn’t getting any better when gas goes below $2 / gallon. This is called a clue.
Thanks much for the eye opening info. We’re building a new home now and I’m thinking about the potential for solar equipment when the collectors tech gets more efficient. Designed our home so that the southern side (rear of the house) has a large, single plane roof to maximize area for panels. But no panels planned yet. And our home will be extremely energy efficient.
I am having a second junction/breaker box installed outside (next to a propane outlet) so that the home will be generator ready in case of a major disaster and extended power outage. My current portable generator runs on gasoline or propane, and hooked into my 500 gal tank, should be able to keep essentials running for an extended period. not everything at once, but lights/fridge/freezer/fans for sure. Cooktop and hot water runs on propane, so that would not play into equations.
I was thinking a technologically advanced solar charged battery system with an inverter would be awesome, but if y’all say the tech isn’t there yet, I’ll pass. But gonna keep an eye on this for down the road. Thanks again!
K
Last year in San Antonio I saw the big municipal owned solar park south of town. SATX is looking like solar country and costs continue to decline, driven in large part by low price Chinese producers. Smart idea building for eventual solar, I would do the same thing in your shoes. Many basic inverters still depend on utility power, the standalone/battery versions often cost more.
It would be great if they could bridge on grid and off grid technology. I helped a friend set up an off grid solar system in his backyard shed using Grape Solar panels, an inverter, and a bank of three deep cell batteries. He set up his shed using 12V RV lights and fans, and the inverter powered his tools. Worked excellent.
Take Care,
Buzz
IMO, the PowerWall is just the first battery system to hit mainstream attention via the hype campaign that is Tesla’s marketing strategy. Buzz, the technology to do those things you want are there. It’s just that until Tesla’s latest media blitz that most of us have never known all the wonderful things the PowerWall promises were possible. Look at my link above- JLM Energy’s Energizr is available now, and is basically the same thing. What the PowerWall does have is a sleek design that is way nicer looking than traditional battery systems, and it is being pushed by a big flashy ad campaign from a company with just one product currently available (the Model S is really all they have ATM). Tesla is just looking to expand their market with a new product at a price point well below that of the Model S.Battery back up on a grid tie PV system is nothing complex (meaning it has been done for a long time). You just need to put in a ton of time and due diligence designing your own system, or fork out some $$$ to have others do it for you.
btw- congrats on the new home. Sounds like you are doing it the right way.
I did check out that Energizr and it looks compelling. Actually like the concept and apparent ease of instillation more than the Tesela based on my unpro opinion.
Our house should be complete sometime around the holidays if all goes well, so solar system is at least another year away unless the there are significant incentives.
I mentioned I’m having a second panel installed for the generator backup…I’ll ensure that we are able to tie into it with the battery system as well, per the diagram at the JLM site.
It’s interesting that the site depicts wind energy as another method to generate energy to share the batteries…I am starting to see small windmills in use around South TX
I really appreciate your inputs. I’ll keep researching, but input and advice from folks much more knowledgable are a huge help. thanks!!!
Take Care,
Buzz
Glad you are finding the help you are looking for. I’ve been kicking PV/battery back up for a while, but the high cost and our low usage has made it economically unfeasible until recently. Still can’t afford the batteries but I’m taking the plunge into a small PV array. Part of this is because the federal tax credit (30%) is set to expire at the end of 2016; unsure when our state credit (10%) is going away but PNM has stopped buying RECs from individuals. They still keep a bank of surplus credits, but until we move or close the account we won’t see a penny for the surplus energy PNM takes from us. And even then, what they pay for our surplus energy is the whole sale rate. You might want to look into your local REC policies and tax credits. Getting PV installed before the end of 2016, because that 30% credit is a huge incentive to give up, and if your local municipality is planning to stop paying for RECs. Your array doesn’t need to produce 100% of your power needs for you to see the benefit, so even a 4-8 panel array will help. One last suggestion- after studying this for a while, I’ve become a big fan of microinverters, especially for small systems, and for those that plan to expand their arrays in the future. Check out Enphase and their micro inverter technology. Pretty cool stuff, and IMHO offers easier installation for the well-prepared DIYer.
Thanks…but I’m missing something…
PV is what…solar power?
Also, I’ll check out the micro inverters. These convert energy, I get that, but “micro”…not sure what this means but I’ll research.
Our power companies also pay lowest rate for energy back to the grid. My preference is to have a way to store my energy for peak hours, which would be afternoon/evening when sun is weak/gone.
Disregard my question, PV: found it…
http://www.fsec.ucf.edu/en/consumer/solar_electricity/basics/how_pv_system_works.htm
Take Care,
Buzz
Micro inverters are simply individual inverters attached to each individual solar panel. Traditionally, a string inverter was used. This is just a giant inverter sized to match the array. This works just fine, but the benefits of micro inverters are: the ability to monitor each panel as a single entity, the abilty to expand your array without changing a single inverter and a cleaner, simpler install. With a string invetter, system output is measured as a whole- you can’t look at a single panel to diagnose its condition. Also, you need to figure what your system voltage and currents will be, and size the wiring accordingly. Also, there are some other things to comsider, like whether your panels are strung together in series or parallel (AFAIK most arrays will be a combination of series-parallel). You’ll also need a more complex wiring layout- all the panels are producing DC power, so they need to joined in a combiner box to ensure that all panel groups are matched in voltage/current out put. Not hard to do, just more calculations and parts involved. The string inverter needs to sized to system out put- you lose efficiency by oversizing, and undersizing means the array puts out too much current for the inverter to handle. If you start small and wish to upgrade in the future you’ll likely need a new larger inverter. Possibly a new larger cable size, too. And lastly, the sitring inverter is a single point of failure. If the inverter goes offline, your entire array is down. Micro inverters allow you to run a single common wire gauge (240 or 208 volts AC output via 12awg cable) so that eliminates the need for combiner boxes and the calulations for series-parallel configurations. Since out put is a common AC, it ties dierectly to your service panel. When you want to expand, whether a single panel or a dozen, no need to run a larger cable gauge or worry about panel layout. You just plug and play the new portion of the array into the existing system. Mocroinverters also allow monitoring their outputs as a single entity, so you can diagnose a decrease in system out put down to indivual panels. there are more comparisons to make, but that’s the gost of it.
I found some more infor re: PowerWall and Energizr back ups. If all the claims of the PowerWall are true, it does offer more capacity than the Engizr, for about the same price. The big thing separating all the battery systems is the construction, materials and cell composition- all batteries are not created equal. If Tesla’s technology is bringing something new to market maybe it is hype worthy. The Energizr data I saw shows about 4.4 kwh, vs the 7-10 kwh promised by PowerWall. Still not exactly an apple-apple comparison since I don’t have physical dimensions to compare them; if the Energizr has a smaller foot print then it might be better for space limited applications. As I mentioned above, without solid engineering specs, there’s speculation and not much else available from Tesla.
Thanks for the update. I’ve been talking with the sales dept at JLM. They don’t really have a system that meets my expectations at this time, although a hybrid/combo of their systems would serve my purposes. My cost would be somewhere between $15-20K, which is more than I’m able to spend any time soon. My first step would be the PV panels.
What I want it a system that does several things…
Produce power during the day from sunlight.
Store power for use during evening and power outages.
Will work in conjunction with a backup generator.
Still in research mode, but your posts have been very helpful. Thanks much!
Take Care,
Buzz