{"id":7991,"date":"2016-10-29T22:06:39","date_gmt":"2016-10-29T12:36:39","guid":{"rendered":"http:\/\/www.solarquotes.com.au\/blog\/?p=7991"},"modified":"2018-01-18T13:05:51","modified_gmt":"2018-01-18T02:35:51","slug":"tesla-powerwall-2","status":"publish","type":"post","link":"https:\/\/www.solarquotes.com.au\/blog\/tesla-powerwall-2\/","title":{"rendered":"The Tesla Powerwall 2: Batteries Can Finally Pay For Themselves"},"content":{"rendered":"
\"Elon

Elon Musk proclaims the coronation of Powerwall 2.0<\/p><\/div>\n

Today at 12:15 Eastern Standard Time, Elon Musk announced the arrival of the Tesla Powerwall 2.<\/p>\n

Some people were enthusiastically looking forward to this announcement, but I was not. I fully expected to be underwhelmed, and as soon as Musk finished his two or three sentences on the actual system, I felt a near fatal lack of enthusiasm sweeping over me.<\/p>\n

From what Musk said, it appeared to simply be two original Powerwalls glued together inside a plastic case.<\/p>\n

I almost died from lack of interest.\u00a0 Fortunately, I had the foresight to have a hypodermic full of adrenaline at the ready, which I was able to jab into my heart and save the Coroner from having to write \u201cTesla induced ennui\u201d on my death certificate.<\/p>\n

Because it appeared to just be two normal Powerwalls attempting to make a baby inside a refrigerator, I assumed today’s announcement was the same as the original Powerwall launch. That is, all hat and very little cattle. Or perhaps I should I say, all Tony Stark and very little Ironman?<\/p>\n

\"at-least-its-better-tha-having-a-boob-window\"

“Well, I got this costume from Nick Fury and I don’t think he likes me very much. What’s your excuse for having a target in the centre of your chest?”<\/p><\/div>\n

But then, an hour or so later, the technical details became available on the Australian Tesla site and I found myself actually becoming interested. It turns out that Elon Musk had left out all the important shit. It appears that the Powerwall 2 is not simply\u00a0two original Powerwalls glued together, but a fundamental redesign.\u00a0 In fact, I became so very interested, I became excited. I almost had to take a Bex and have a nice lie down to counteract the effects of the adrenaline.<\/p>\n

It turns out that it has a built in inverter and according to Tesla the 14 kilowatt-hour Powerwall 2 could be installed for under AUD $10,000.1<\/a><\/sup><\/p>\n

31 October Update:<\/strong> Tesla advise that the costs on the website do not include GST but are otherwise correct retail pricing for Australia. \u00a0<\/em><\/p>\n

Now that is a major change.\u00a0 If the estimated cost of installation that Tesla gave is correct, it means that, under a limited set of circumstances, battery storage could finally pay for itself for a limited number of Australians.<\/p>\n

The Powerwall 2 Tech Specs<\/h2>\n

Here are the Powerwall 2 technical specifications I nabbed right off the Tesla Australia website:<\/p>\n

\"Powerwall

Powerwall 2 technical details. (Image credit: Tesla)<\/p><\/div>\n

Update (4th Nov):\u00a0\u00a0<\/strong>On Tesla’s American website the weight of the Powerwall 2 is now given as 120kg. \u00a0<\/em><\/p>\n

It Has A Built In Inverter!<\/h2>\n

The most interesting thing about the Powerwall 2, which Elon Musk completely failed to mention, is that it has an inverter built into it.\u00a0 I had heard rumors that it would, but I didn’t believe them on account of how it would be useful.<\/p>\n

This is big news.\u00a0 It means there is no need to go through the expense of buying a multimode inverter or other device to install it and it makes installation quicker and easier and therefore cheaper.<\/p>\n

Why Musk didn’t mention this, I don’t know.\u00a0 Maybe he is paid by the word and the board of directors decided they couldn’t afford to having him mention it or perhaps he is terrified of public speaking and every word is agony for him.<\/p>\n

Battery Capacity<\/h2>\n

With 13.5 kilowatt-hours of usable storage, the Powerwall 2 has over twice the capacity of the original, which could store 6.4 kilowatt-hours when new.<\/p>\n

It’s Too Much For Most Aussie Households Right Now<\/h2>\n

The high storage capacity of the Powerwall 2 will make it difficult for most households to use it all in an evening.\u00a0 The average Sydney household without gas uses an average of around 17.6 kilowatt-hours a day and perhaps half that overnight.\u00a0 This means only very large or very wasteful households are likely to be able to use a Powerwall 2 at full capacity for ‘solar shifting’ and so get the best possible return on the battery system.<\/p>\n

Where the extra capacity may come in useful is to stretch out how many hours you can run in backup mode. Might be handy if any of those wind turbines conspire to blow down electricity transmission towers<\/a> again.<\/p>\n

And when Elon Musk’s master plan is complete and everyone has an electric car, the extra capacity might be useful too.<\/p>\n

But bear in mind that\u00a0being a lithium-ion battery, that capacity will soon start to diminish.\u00a0 After 10 years it might be down to 70% or less.<\/p>\n

Power<\/h2>\n

Elon Musk said that, compared to the original, the Powerwall 2 has:<\/p>\n

“More than twice as much power.”<\/p><\/blockquote>\n

It does not.\u00a0 The specs show that the Powerwall 2 is able to provide 5 kilowatts of continuous power, 7kW peak. The original Powerwall was 3.3 continuous, 5kW peak. The Powerwall 2 has 50% more continuous power than the original. This is surprisingly low considering it has twice the storage capacity.<\/p>\n

In his announcement Musk said 7 kilowatts, but that is misleading because it is the peak power which might only be for a second or two.\u00a0He appears to be mistakenly\u00a0comparing the peak power of the Powerwall 2 with the continuous power of the original Powerwall. And that’s misleading.<\/p>\n

Additional Misleading Statement!<\/h2>\n

Elon Musk said:<\/p>\n

“You can take a four bedroom house and you can have, er, you can power the, your fridge, the sockets, and lights, ah, for a day.”<\/p><\/blockquote>\n

This statement is misleading because many people will, quite reasonably, conclude he is saying an entire typical large home can be completely run off a Powerwall 2 for a full 24 hours.\u00a0 This is not true because the average Australian and American house uses more than 13.5 kilowatt-hours in a day.\u00a0 Most people won’t realize that, “…your fridge, the sockets, and lights…” does not include air conditioning, heating, hot water systems, or stoves, all of which are big users of electricity.<\/p>\n

If Elon Musk were a salesperson in Australia you could argue that he just claimed the product was suitable for a purpose that it is not. \u00a0And under Australian Consumer Law, you\u00a0could be entitled to a refund 2<\/a><\/sup>.<\/p>\n

Inverter Size<\/h2>\n

Because the Powerwall 2 can provide a continuous 5 kilowatts, we know the inverter must be 5 kilowatts or more in size.\u00a0 Because its peak power is 7 kilowatts perhaps that means the inverter capacity is the same, but that might actually be the peak capacity of the inverter and its actual rated capacity could be less.\u00a0 So all I can say for now is it’s 5 kilowatts or more.<\/p>\n

Update\u00a0(31 Oct): <\/strong>Tesla have advised that my assumptions about the inverter are wrong – and that they’ll disclose the full inverter spec ‘shortly’. The tension is killing me.<\/em><\/p>\n

Size, Weight, And Style<\/h2>\n

The Powerwall 2 is 115cm tall, 75.5cm wide, and only 15.5 centimeters deep.\u00a0 But the bracket that holds it to the wall may mean its depth is effectively greater than that.\u00a0 It is significantly smaller than the original despite having more than twice the usable capacity.<\/p>\n

At 110kg it is only 10% heavier than the original.\u00a0 This comes to 8.15 kilograms per kilowatt-hour, which beats the LG Chem’s RESU10 at 8.52kg\/kWh.<\/p>\n

Update (4th Nov):<\/strong>\u00a0\u00a0On Tesla’s American website the weight of the Powerwall 2 is now given as 120kg.\u00a0 The figures below have been adjusted to account for this.
\n<\/em><\/p>\n

Update (31 Oct):\u00a0<\/strong>Tesla have advised that the Powerwall 2 has AC coupling built in. They say a fair comparison would include the DC coupled LG Resu’s weight + an AC Inverter’s weight. Fair call. The Solax\u00a0SK-SU5000E Hybrid Inverter<\/a>\u00a0weighs 23kg, LG RESU10 weighs 75kg, total weight = 98kg. 98kg\/8.8kWh = 11.14kg\/kWh for the RESU+Inverter compared to 8.89 for the Tesla unit3<\/a><\/sup>.<\/em><\/p>\n

As for the new design, its design is quite simple – a large, flat rectangle.\u00a0 I’m glad they didn’t keep their original design because to me that always looked like a coffin with the word TESLA stamped on it.\u00a0 While I’ve got nothing against Nikola, the thought of his ghostly remains powering my house always struck me as a bit creepy. \u00a0 <\/span><\/p>\n

Indoors, Outdoors, On-Grid, Off-Grid<\/h2>\n

According to the limited information Tesla has provided, it appears the Powerwall 2 can be installed indoors or outdoors, on the ground or on a wall. \u00a0When on-grid it can provide back up power during a blackout and is suitable for use off-grid.\u00a0 If all this is true, it makes it a very flexible system.<\/p>\n

Warranty<\/h2>\n

The warranty is for 10 years and that’s all I can tell you at this point.\u00a0 I have no idea if it will be similar to the weird one<\/a> the current Powerwall has, which says it doesn’t cover batteries that suffer normal degradation but doesn’t define what that is.<\/p>\n

Because the power output of the Powerwall 2 is lower per kilowatt-hour of storage than the original, that will have a beneficial effect on the lifespan of the batteries and so its warranty may be considerably better.<\/p>\n

Battery Deterioration<\/h2>\n

Lithium-ion batteries decay with use and over time even when not used.\u00a0 Based on the warranty of the original Powerwall when first released, I would roughly estimate that if the Powerwall 2 is cycled once per day, then it may retain 70% of its original capacity by the time it reaches the end of its 10 year warranty.\u00a0 It could be more, it could be less.\u00a0 The only certain thing is it will decrease.\u00a0 There is nothing that can stop that.<\/p>\n

Price<\/h2>\n

The price of the Powerwall 2 is where it gets interesting.\u00a0 I want to be very clear about the source of the figures I am going to give you, so I stole this image from Tesla’s Australian website:<\/p>\n

\"A

A screen capture of the Tesla Powerwall 2 price and installation estimate from Tesla’s Australian website. (Image credit: Tesla)<\/p><\/div>\n

So, as you can see, I didn’t pull these figures out of my ass.\u00a0 I pulled them out of Tesla’s shiny ass.<\/p>\n

Update (31st Oct):<\/strong> It turns out that Tesla’s shiny ass4<\/a><\/sup> has gotten its figures wrong.\u00a0 I have been contacted by Tesla (the company, not the ghost) who have told me the price they gave doesn’t include GST.\u00a0 This means the price of the Powerwall 2 including GST is $8,800.\u00a0 Their estimate for the cost of installation also didn’t include GST, so that will come to $1,595.\u00a0 So according to Tesla, the total cost of an installed Powerall 2 will be $10,395.\u00a0 At the time I am writing this, they still haven’t corrected their Australian website.
\n<\/em><\/p>\n

This makes everything 10% worse.\u00a0 I have gone through my calculations below and adjusted them to take the correction into account.\u00a0 I haven’t removed the “Yeah, baby, yeah!” video clip, so please just imagine that Austin Powers is saying it 10% less enthusiastically.<\/em><\/p>\n

Tesla says the Powerwall 2 could be fully installed for roughly the same cost as an original Powerwall.\u00a0 If Tesla’s estimate of $10,395 is correct, they have halved the installed cost per kilowatt-hour.\u00a0 This means Tesla has finally done it!\u00a0 After all this time they have finally managed to produce a battery system for around the same cost per stored kilowatt-hour as they implied<\/a> the original Powerwall would cost!\u00a0 And here I was thinking Tesla was full of shit and would remain full of shit forever more.\u00a0 But it turns out they just needed a little time to work their way up to actually doing what they said they would.<\/p>\n

The cost of the Powerwall 2 in America is $5,500 US.\u00a0 This means, at the current exchange rate and accounting for GST, Australians are being charged $839 more.\u00a0 Possibly as revenge for all the horrible, nasty, true things I’ve said about the Powerwall in the past.\u00a0 After all, it doesn’t cost that much to ship 110kg over from California and hedging against currency fluctuations doesn’t either.<\/p>\n

Does It Pay For Itself?<\/h2>\n

Does the Tesla Powerwall 2 pay for itself?<\/p>\n

Step 1:<\/strong>\u00a0 Imagine I’ve put a whole list of caveats here.\u00a0 Enough caveats to build an empire.<\/p>\n

Step 2:<\/strong> Yes.<\/p>\n