6 ms·

Tesla Powerwall: Crunching the Numbers for Australia

64 points by qzervaas 11y ago

yitchelle 11y ago
Kinda sad situation with the alternative energy source. I did a similar back of the envelope calculation for my dad when he considered putting solar panels onto his house roof when the Australian Govn't was subsidizing it. It would have taken him 17 years to breakeven from the initial installation. This did not even consider the maintenance and insurance cost. We weren't even sure if my parents would have stayed in that house for that long. So we skipped it. The initial costs is just too high for average Joe.
- dragontamer 11y ago
  Its as if people have forgotten about infrastructure or something. https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Station https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta... Spend a few billion on a 3 Gigawatt plant (roughly 30-Gigawatt hours of energy storage). Large-scale infrastructure projects are going to be cheaper and more efficient than most direct-to-home solutions. The economies of scale, and the innovative designs that exist at the large level (CAES: Compressed Air Energy Storage. Redox-Flow Batteries, Pumped Hydro, Flywheel Energy Storage) are superior to the designs that exist at a micro-level (Li-Ion Batteries) The new infrastructure projects are occurring all over the place in the US. * http://www.energy.ca.gov/tour/helms/ http://www.energy.ca.gov/tour/helms/ * https://www.greentechmedia.com/articles/read/texas-calls-for-317mw-of-compressed-air-energy-storage2 https://www.greentechmedia.com/articles/read/texas-calls-for... Etc. etc. These infrastructure projects are the future (and past). They're proven, reliable, and there are tons of engineers with decades of experience on these sorts of projects. -------- Tesla needs to try to make a Utility-scale 500 MW plant.
  - yellowbkpk 11y ago
    Those infrastructure projects don't sell Tesla batteries at scale, making future Tesla battery packs cheaper, making future Tesla cars cheaper.
  - mikeash 11y ago
    Tesla is making utility-scale stuff. Their "Powerpack" product starts at 100kWh and can be chained together to scale as large as you want, and is intended for industrial and utility use. The home version is basically a byproduct of that, for people who want a whole-house UPS, or really want to go off-grid, or whose utilities are slow to get with it.
- mhurron 11y ago
  > Kinda sad situation with the alternative energy source. I find it kind of sad that the only way people will consider alternative energy sources is if it's significantly cheaper than the existing, embedded, kill the planet options. I find it sad, but I'm not surprised. People in general don't actually give a shit about anything around them.
  - escherize 11y ago
    You should cheer up. Rational people (like gp) only care about what's around them. Why should he waste money on solar instead of sending it to charity, etc?
    - Brakenshire 11y ago
      The Rational Man is a economic construct which is dubious as an abstract concept for building economic models, and irrelevant as a justification for individual behaviour. If the limit of morality is the law and the market, we might all just as well give up now.
      - oldmanjay 11y ago
        Apologies for this comment. I dashed off about 30% of my thoughts (the shittiest 30%) and this isn't really what I was trying to express. I'll leave it here to remind myself to think more. ----- If the most convincing case you can make for your morals is "you should because I say so" then you can't be too surprised when it's not 100% convincing to people.
        Brakenshire 11y ago
        > If the most convincing case you can make for your morals is "you should because I say so" then you can't be too surprised when it's not 100% convincing to people. Yeah, there are all sorts of questions you can discuss about how your values inform the way you spend money above and beyond what's necessary, whether it's about luxury, convenience, status, or how you would want to spend charitable money. What annoyed me was the raising up of an observation ('people don't care about anything beyond their surroundings') into something which is glibly justified because it is Rational. I would say that's a "you should because I say so", or at best a "you should because it is" argument for morality. Edit: Ah, I see your edit, consider the above part of the fossilized argument then!
- singingfish 11y ago
  I've done some sums too. A 4kw system without storage has a payback time of 10 years for me. I can't see storage making an economic difference at this stage.
ljoshua 11y ago
Interesting to see the different power usage and electricity rates for a different part of the globe. Here in the Houston, TX area we used 848 kWh in a 30 day winter period for a mid-sized home, which is as much as the article states the household used in a 95 day period. During the summer, when my old AC unit is running like crazy, we'll use ~1800 kWh, and our rate is an average of $0.102 USD, which is around 60% of the top rate from the article. A Powerwall unit still wouldn't make sense for us, but this is rev 1, and so in a couple of generations we could be looking at something that actually could be impactful.
- merb 11y ago
  848 kWh sounds a lot. For a 4 person house in germany you have a yearly usage ~1800kWh. You have the same amount in a 1/3 year. That's a shitload. Currently I'm single and use 848 kWh for a whole year.
  - noselasd 11y ago
    That sounds so little. Just having two 50W lightbulbs shining 24x7 would be slightly more than that in a year.
    - merb 11y ago
      Currently I'm below average something like 200kWh below. However currently I'm only at home on Sundays, all other days I'm only be here to sleep and eat, however I barely cook, so a toaster and breed doesn't use so much energy and I have LED's everywhere so I use max. 7W per room (2 rooms total + 1 bath) however I turn off the light's after leaving a room. I have no dishwasher and my watching machine is really really good when it comes to energy. I barely watch TV and I use my MacBook for surfing which gets loaded at my company (I use it there, too). So I only need a light with 7W for like 4 Hours, have a router running 24/7 which consumes nearly nothing. I'm a single. So no problem there. (Btw. my invoice for food is definitely higher than most ;)) oh and btw. in germany energy isn't as cheap as in the usa. also if you use solar energy in germany you could only use 30% since the rest goes to the public (and you get nearly nothing for that).
rhino369 11y ago
Not to mention, if people actually used these in large enough numbers--or utilities building a battery reserve--the off peak power and peak power difference will be smaller. Because you have increased demand for off peak due to charging. And decreased peak usage.
- keithpeter 11y ago
  That smoothing out of the daily demand curve might actually lead to significant capital savings on the part of utility companies as less need for short term high power reserve. Also the resilience of the system to problems would increase. UK is providing a degree of subsidy to reduce peak demand already. Smart meters may help in future. http://www2.nationalgrid.com/uk/Industry-information/Electricity-transmission-operational-data/Data-Explorer/ http://www2.nationalgrid.com/uk/Industry-information/Electri... http://www.eunomia.co.uk/eunomia-supports-uks-first-electricity-demand-reduction-auction/ http://www.eunomia.co.uk/eunomia-supports-uks-first-electric... http://www.carbonbrief.org/how-national-grid-keeps-the-lights-on-when-a-large-power-station-catches-fire http://www.carbonbrief.org/how-national-grid-keeps-the-light...
grecy 11y ago
The price for solar is not accurate in this article. My parents just installed a 5KW system, with an inverter and smart meter in Warrnambool, Victoria. They paid $10k AUD, then the government refunded them $5k, so total out of pocket expense for them was only $5k
oconnore 11y ago
The whole notion of the powerwall is based on the assumption that either utilities or consumers are irrational. If buying a powerwall was at all economical, utilities would buy them in bulk, charge them on wholesale power, alter their pricing structure, and make a larger margin than you ever could. If powerwalls aren't economical, the only reason they make sense is to capitalize on consumers who are willing to buy the thing because its cool, or because they like living "off the grid". Utilities also have access to utility-scale energy storage -- pumped hydro, thermal, etc -- which is far cheaper than consumer focused powerwalls.

64 points by qzervaas 11y ago

Kinda sad situation with the alternative energy source. I did a similar back of the envelope calculation for my dad when he considered putting solar panels onto his house roof when the Australian Govn't was subsidizing it. It would have taken him 17 years to breakeven from the initial installation. This did not even consider the maintenance and insurance cost. We weren't even sure if my parents would have stayed in that house for that long. So we skipped it. The initial costs is just too high for average Joe.

dragontamer 11y ago
Its as if people have forgotten about infrastructure or something. https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Station https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta... Spend a few billion on a 3 Gigawatt plant (roughly 30-Gigawatt hours of energy storage). Large-scale infrastructure projects are going to be cheaper and more efficient than most direct-to-home solutions. The economies of scale, and the innovative designs that exist at the large level (CAES: Compressed Air Energy Storage. Redox-Flow Batteries, Pumped Hydro, Flywheel Energy Storage) are superior to the designs that exist at a micro-level (Li-Ion Batteries) The new infrastructure projects are occurring all over the place in the US. * http://www.energy.ca.gov/tour/helms/ http://www.energy.ca.gov/tour/helms/ * https://www.greentechmedia.com/articles/read/texas-calls-for-317mw-of-compressed-air-energy-storage2 https://www.greentechmedia.com/articles/read/texas-calls-for... Etc. etc. These infrastructure projects are the future (and past). They're proven, reliable, and there are tons of engineers with decades of experience on these sorts of projects. -------- Tesla needs to try to make a Utility-scale 500 MW plant.
- yellowbkpk 11y ago
  Those infrastructure projects don't sell Tesla batteries at scale, making future Tesla battery packs cheaper, making future Tesla cars cheaper.
- mikeash 11y ago
  Tesla is making utility-scale stuff. Their "Powerpack" product starts at 100kWh and can be chained together to scale as large as you want, and is intended for industrial and utility use. The home version is basically a byproduct of that, for people who want a whole-house UPS, or really want to go off-grid, or whose utilities are slow to get with it.
mhurron 11y ago
> Kinda sad situation with the alternative energy source. I find it kind of sad that the only way people will consider alternative energy sources is if it's significantly cheaper than the existing, embedded, kill the planet options. I find it sad, but I'm not surprised. People in general don't actually give a shit about anything around them.
- escherize 11y ago
  You should cheer up. Rational people (like gp) only care about what's around them. Why should he waste money on solar instead of sending it to charity, etc?
  - Brakenshire 11y ago
    The Rational Man is a economic construct which is dubious as an abstract concept for building economic models, and irrelevant as a justification for individual behaviour. If the limit of morality is the law and the market, we might all just as well give up now.
    - oldmanjay 11y ago
      Apologies for this comment. I dashed off about 30% of my thoughts (the shittiest 30%) and this isn't really what I was trying to express. I'll leave it here to remind myself to think more. ----- If the most convincing case you can make for your morals is "you should because I say so" then you can't be too surprised when it's not 100% convincing to people.
      - Brakenshire 11y ago
        > If the most convincing case you can make for your morals is "you should because I say so" then you can't be too surprised when it's not 100% convincing to people. Yeah, there are all sorts of questions you can discuss about how your values inform the way you spend money above and beyond what's necessary, whether it's about luxury, convenience, status, or how you would want to spend charitable money. What annoyed me was the raising up of an observation ('people don't care about anything beyond their surroundings') into something which is glibly justified because it is Rational. I would say that's a "you should because I say so", or at best a "you should because it is" argument for morality. Edit: Ah, I see your edit, consider the above part of the fossilized argument then!
singingfish 11y ago
I've done some sums too. A 4kw system without storage has a payback time of 10 years for me. I can't see storage making an economic difference at this stage.

ljoshua 11y ago

Interesting to see the different power usage and electricity rates for a different part of the globe. Here in the Houston, TX area we used 848 kWh in a 30 day winter period for a mid-sized home, which is as much as the article states the household used in a 95 day period. During the summer, when my old AC unit is running like crazy, we'll use ~1800 kWh, and our rate is an average of $0.102 USD, which is around 60% of the top rate from the article. A Powerwall unit still wouldn't make sense for us, but this is rev 1, and so in a couple of generations we could be looking at something that actually could be impactful.

merb 11y ago
848 kWh sounds a lot. For a 4 person house in germany you have a yearly usage ~1800kWh. You have the same amount in a 1/3 year. That's a shitload. Currently I'm single and use 848 kWh for a whole year.
- noselasd 11y ago
  That sounds so little. Just having two 50W lightbulbs shining 24x7 would be slightly more than that in a year.
  - merb 11y ago
    Currently I'm below average something like 200kWh below. However currently I'm only at home on Sundays, all other days I'm only be here to sleep and eat, however I barely cook, so a toaster and breed doesn't use so much energy and I have LED's everywhere so I use max. 7W per room (2 rooms total + 1 bath) however I turn off the light's after leaving a room. I have no dishwasher and my watching machine is really really good when it comes to energy. I barely watch TV and I use my MacBook for surfing which gets loaded at my company (I use it there, too). So I only need a light with 7W for like 4 Hours, have a router running 24/7 which consumes nearly nothing. I'm a single. So no problem there. (Btw. my invoice for food is definitely higher than most ;)) oh and btw. in germany energy isn't as cheap as in the usa. also if you use solar energy in germany you could only use 30% since the rest goes to the public (and you get nearly nothing for that).

rhino369 11y ago

Not to mention, if people actually used these in large enough numbers--or utilities building a battery reserve--the off peak power and peak power difference will be smaller. Because you have increased demand for off peak due to charging. And decreased peak usage.

keithpeter 11y ago
That smoothing out of the daily demand curve might actually lead to significant capital savings on the part of utility companies as less need for short term high power reserve. Also the resilience of the system to problems would increase. UK is providing a degree of subsidy to reduce peak demand already. Smart meters may help in future. http://www2.nationalgrid.com/uk/Industry-information/Electricity-transmission-operational-data/Data-Explorer/ http://www2.nationalgrid.com/uk/Industry-information/Electri... http://www.eunomia.co.uk/eunomia-supports-uks-first-electricity-demand-reduction-auction/ http://www.eunomia.co.uk/eunomia-supports-uks-first-electric... http://www.carbonbrief.org/how-national-grid-keeps-the-lights-on-when-a-large-power-station-catches-fire http://www.carbonbrief.org/how-national-grid-keeps-the-light...

grecy 11y ago

The price for solar is not accurate in this article. My parents just installed a 5KW system, with an inverter and smart meter in Warrnambool, Victoria. They paid $10k AUD, then the government refunded them $5k, so total out of pocket expense for them was only $5k

oconnore 11y ago

The whole notion of the powerwall is based on the assumption that either utilities or consumers are irrational. If buying a powerwall was at all economical, utilities would buy them in bulk, charge them on wholesale power, alter their pricing structure, and make a larger margin than you ever could. If powerwalls aren't economical, the only reason they make sense is to capitalize on consumers who are willing to buy the thing because its cool, or because they like living "off the grid". Utilities also have access to utility-scale energy storage -- pumped hydro, thermal, etc -- which is far cheaper than consumer focused powerwalls.