After a year of use, Tesla Powerwall systems are performing well with 90% utility savings

William Gayde

Posts: 375   +5
Staff member

Solar power is typically seen as the most viable source of renewable energy to the average homeowner. The only issue is that the sun only shines for part of the day. What do you do during the night or on cloudy days? If you ask Tesla, you purchase a Powerwall to help store your excess energy and save it for later. When Tesla first announced the Powerwall in 2015, they had grand dreams for the system. According to an interview with one of the first customers, Tesla's claims are coming to fruition.

Nick Pfitzner, an Australian homeowner, purchased a $13,000 solar system in early 2016. This includes solar panels, a SolarEdge inverter, a 7 kWh Powerwall battery, and an intelligent Reposit monitoring system. This unique and slightly more complex than normal system has helped him achieve a 92% savings in utility costs over his first year. Most solar installations don't include a battery or monitoring system, but that's the key to his efficiency and savings.

With the Powerwall, Pfitzner is able to store excess power that his house doesn't use. The intelligent monitoring system then tracks numerous factors including weather patterns, predicted energy use, and current utility prices. This allows him to sell back the electricity stored in his Powerwall to the grid at the optimum time to make the most profit.

Australia, with its high electricity rates and lots of sunshine, is a prime spot for solar adoption. Traditional solar systems have a return on investment period of 10-15 years, but these new Powerwall equipped systems are nearly cutting that in half. Pfitzner expects to pay off his system in eight years, much less than Tesla's original launch projections of 14-18 years.

Permalink to story.

 

RedGuard

Posts: 80   +39
Well, my electricity bill is, let's say, 55 euros per month. 660 euros per year.

It will absorb the $13,000 investment in... 18 years? If I only use the solar energy provided by it.

Yeah, no. Not worth it for 90% of the globe. Pardon, earning 3,000 EUR net per month makes one be in TOP 0.54% of the global population (so that you can spend that high amount of money for the investment - cause you have to pay other things out of those 3,000 euros every month, too).
 

Rippleman

Posts: 871   +393
Well, my electricity bill is, let's say, 55 euros per month. 660 euros per year.

It will absorb the $13,000 investment in... 18 years? If I only use the solar energy provided by it.

Yeah, no. Not worth it for 90% of the globe. Pardon, earning 3,000 EUR net per month makes one be in TOP 0.54% of the global population (so that you can spend that high amount of money for the investment - cause you have to pay other things out of those 3,000 euros every month, too).
although financial incentive is the main driving factor for most things on earth, think of this as a problem-solving solution rather then a money saving solution. Imagine if EVERYONE had this system. The amount of power saved per-day Earth wide would be amazing.

As with all revsions, things always get cheaper after more adopt it, manufacturing gets cheaper, more efficient etc etc. It will go down in price.
 

Greg S

Posts: 1,607   +442
The amount of power saved per-day Earth wide would be amazing.
These don't save any power, they just store it for later use. This is actually just reducing the amount of power that large plants have to generate because the individual user is generating for themselves. It doesn't reduce overall consumption particularly.
 

Rippleman

Posts: 871   +393
These don't save any power, they just store it for later use. This is actually just reducing the amount of power that large plants have to generate because the individual user is generating for themselves. It doesn't reduce overall consumption particularly.
Let me reword: The amount of resources saved by not having to have energy be produced by traditional sources per-day Earth wide would be amazing.

Technically if you want to get word-critical, I am still correct... you are "saving" the power for later. :)
 

Kibaruk

Posts: 3,836   +1,183
To get something back in 8-10 years, is still a really long long run investment, are maintenance covered on the wall? Is it going to last that long? Ok let's say instead of that, the average estimated of 15 years. Also considering he is selling back power, which will vary depending on where you live, and how many people live in that house.

Don't get me wrong, I LOVE the idea and usage of alternative sources of energy, like sun powered, yet it's too much down the road. Maybe this paired with a water heater... he may have, I don't know, there is not enough information to determine a lot of things and factors.

Edit: In the main interview it's all there
Powering the home with electricity in 2015 cost him $2289.
WOW.
 

MonsterZero

Posts: 585   +336
These are awesome, sure the upfront cost is pretty substantial but you reap the benefits year over year.

There are kickbacks from your power company and even state rebates for installing a solar setup, not to mention if you had big enough batteries you could sell your power back to the grid and break even on your power bill.
 

RobStow

Posts: 62   +22
Well, my electricity bill is, let's say, 55 euros per month. 660 euros per year.

It will absorb the $13,000 investment in... 18 years? If I only use the solar energy provided by it.

Yeah, no. Not worth it for 90% of the globe. Pardon, earning 3,000 EUR net per month makes one be in TOP 0.54% of the global population (so that you can spend that high amount of money for the investment - cause you have to pay other things out of those 3,000 euros every month, too).
If your power bill is that low then you probably use less than half as much power as the man this article is about and thus could probably get by with a substantially smaller solar + Powerwall investment.

60 Euros is about $83 Cdn. In my area (Moose Jaw, SK, Canada) $83 would be at the high end for single-person monthly power consumption or the low end for a couple. It is easy for families in houses to hit $250/month if they like to keep it cool when it is 35 C outside or warm when it is -35 C inside.
 

RobStow

Posts: 62   +22
To get something back in 8-10 years, is still a really long long run investment, are maintenance covered on the wall? Is it going to last that long? Ok let's say instead of that, the average estimated of 15 years. Also considering he is selling back power, which will vary depending on where you live, and how many people live in that house.

Don't get me wrong, I LOVE the idea and usage of alternative sources of energy, like sun powered, yet it's too much down the road. Maybe this paired with a water heater... he may have, I don't know, there is not enough information to determine a lot of things and factors.

Edit: In the main interview it's all there
Powering the home with electricity in 2015 cost him $2289.
WOW.
The Powerwall is apparently based on lithium-ion batteries. For phones/tablets/laptops the best lithium-ion batteries are good for about 1000 discharge/recharge cycles before the capacity of the battery drops enough to warrant replacement - no idea if the Powerwall will be better or worse than that.
 

Rippleman

Posts: 871   +393
To get something back in 8-10 years, is still a really long long run investment, are maintenance covered on the wall? Is it going to last that long? Ok let's say instead of that, the average estimated of 15 years. Also considering he is selling back power, which will vary depending on where you live, and how many people live in that house.

Don't get me wrong, I LOVE the idea and usage of alternative sources of energy, like sun powered, yet it's too much down the road. Maybe this paired with a water heater... he may have, I don't know, there is not enough information to determine a lot of things and factors.

Edit: In the main interview it's all there WOW.
how do you get "down the road" with out moving towards it?
 

Rippleman

Posts: 871   +393
If your power bill is that low then you probably use less than half as much power as the man this article is about and thus could probably get by with a substantially smaller solar + Powerwall investment.

60 Euros is about $83 Cdn. In my area (Moose Jaw, SK, Canada) $83 would be at the high end for single-person monthly power consumption or the low end for a couple. It is easy for families in houses to hit $250/month if they like to keep it cool when it is 35 C outside or warm when it is -35 C inside.
moosejaw? hahaha, my mothers side comes from there (where she grew up). I have been there a couple times.
 
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insect

Posts: 349   +132
Powering the home with electricity in 2015 cost him $2289. WOW.
Seems about right. My bills during the hottest/coldest (I live in a temperate climate with 4 seasons) is ~$250/month. During a particularly cold winter month last year we had a $400 bill. Heat pumps aren't meant for <20-deg weather.

I'll probably get a system like this for my next, and last before retirement, home (plan on moving in the next 5-8 years, market dependent). $20K that earns itself back, then starts saving me a lot of money - heck yes! A kitchen remodel alone costs that much.
 

Kibaruk

Posts: 3,836   +1,183
how do you get "down the road" with out moving towards it?
If they can assure it will work for the 15-20 years it takes to pay it back, and more, sure. We will see down the road how long it will last and how much it costs to maintain.
 

Evernessince

Posts: 5,413   +5,997
These likely increase the value of your house as well. Really the money saved/made with the system is just icing on the cake in addition to being completely independent from the grid.
 

captaincranky

Posts: 16,121   +4,895
Everyone seems to have forgotten Musk's s scam, when he was trying to sell the battery packs by themselves, without the solar panels. Which in reality, would have cost you money, the energy wasted during the charging process.

These don't save any power, they just store it for later use. This is actually just reducing the amount of power that large plants have to generate because the individual user is generating for themselves. It doesn't reduce overall consumption particularly.
Yeah but, you get the electricity for nothing, and the system is ostensibly environmentally neutral. So "consumption" shouldn't matter. As population increases, consumption would go up anyway, and pollution would get worse, assuming we are relying on large power plants for the bulk of our electricity.

I'm certainly not a fan of Musk, and I doubt if he's the only one in the solar. power business. But he did convince Matsushita to build an enormous battery factory here in the US

OTOH, if we strip mine half the planet gathering silicon, lithium, and other materials necessary for solar power, that's where pollution rears it's ugly head.
 
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Kibaruk

Posts: 3,836   +1,183
Everyone seems to have forgotten Musk's s scam, when he was trying to sell the battery packs by themselves, without the solar panels. Which in reality, would have cost you money, the energy wasted during the charging process.
I don't see it as a scam, it's a reservoir that you can use when there are blackouts or what not, sure, you would still use energy from the main electrical distribution system, but it wouldn't be "over charging". As a backup system I don't think it's bad (Instead of a noisy diesel generator, and if you have the dough).
 

captaincranky

Posts: 16,121   +4,895
I don't see it as a scam, it's a reservoir that you can use when there are blackouts or what not, sure, you would still use energy from the main electrical distribution system, but it wouldn't be "over charging". As a backup system I don't think it's bad (Instead of a noisy diesel generator, and if you have the dough).
Pun Intended..;) Moving on......

Musk's "battery wall", is the most expensive UPS on the planet. And obviously it would go dead in a finite period of time. Like any other UPS you would have to buy the system according to likely need. However, if we're to "future proof the system", we need to take into account projected needs. For true "eco-warriors", those needs will increase, as you're going to have to charge your Tesla off that wall.

I'm "fortunate enough" to live in an area which natural disasters honestly take great pains to avoid. The longest power outage Ive suffered in recent memory (3 or 4 years ago ?), was a couple of hours when the step down transformer on the corner blew a fuse....Such is life in the big city. OTOH, the surrounding counties have had up to a half million interruptions, which have gone on in some cases, for days. A battery alone in those locations, I don't think would cut it.

Plus, I think solar power has long been proven to be viable, well before Musk "invented it". I've seen solar panels on roofs in central New Jersey, probably as long as 30 years ago. Battery technology has advanced by leaps and bounds in those years as well, and Musk is in no way responsible for that either
 
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U.S. real world example: I have a 5K system, southern azimuth, and plenty of Nevada sunshine. System after rebates- $12K (2013)/ Unavoidable electrical bill costs +-$20/mo - $240/yr. 3 year avg. electrical costs less unavoidables - $1,200/yr. I'm already somewhere approaching a 7 year break even with the energy price increases we expect here.

Guessing a percentage of the battery assisted energy only purchased costs of what, 60%?, it would take quite a while to break even with the cost of the energy I now get billed for. But I would almost be willing to do it just to keep my money out of Buffett's hands (he owns NVEnergy).
 

DaveBG

Posts: 513   +215
If this was available in my country I would get one. We have very high price for electricity and this will pay for itself in less than those 8 years mentioned.
 

captaincranky

Posts: 16,121   +4,895
...[ ]....Guessing a percentage of the battery assisted energy only purchased costs of what, 60%?, it would take quite a while to break even with the cost of the energy I now get billed for. But I would almost be willing to do it just to keep my money out of Buffett's hands (he owns NVEnergy).
OK, if you have to buy energy to charge a battery, you can never break even, you just use electricity from the grid to keep the batteries charged, it's as simple as that.

Unless that's not what you're trying to say?
 
'twasn't......I was trying to say, the software I've investigated allows input from the solar panels to the battery -then- back to the house use only. When too little is detected it then draws energy from the grid. It draws energy from the grid to feed the house under those conditions and not the batteries.
What we have in Nevada is an established 2 way path with the power company. If I generate more than I use in real time it goes to my neighbor (the grid). I get paid less than he pays for it and less than I pay when I have to buy it. I would prefer storing my excess for my own consumption, and only purchasing what I absolutely must.