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Can you quote costs here? How much will it cost me to install a battery that lets me come home from work, turn on the air conditioner for 3-4 hours, run 2 loads

Can you quote costs here? How much will it cost me to install a battery that lets me come home from work, turn on the air conditioner for 3-4 hours, run 2 loads through my washer and dryer (cause I have 3 kids), do a load of dishes, all while running the water heater, lights, etc? Does a single $4,000 power-wall do that? And if it is merely saving me the cost differential from electricity at noon and electricity at 6pm, is it going to pay itself off in less than 15 years?

antisthenes 9y ago
It would be more efficient to cool the home while you're not there than to turn on AC immediately after you come home from work in a hot home. > run 2 loads through my washer and dryer (cause I have 3 kids) Surely you don't run 2 loads through your washer and dryer _EVERY_ day, do you? Do your children change clothes every 2 hours? Do you change bedding and towels every day? Point being, I can come up with incredibly inefficient and wasteful scenarios too and then say "well, it doesn't serve my needs either, see!" Shifting energy usage patterns is just as much part of being green as is generating energy in a renewable way. Just because you can come up with a scenario that isn't 100% addressed by that, doesn't mean it's not worth doing in aggregate.
- coryfklein 9y ago
  > Surely you don't run 2 loads through your washer and dryer _EVERY_ day, do you? No, but I need to be able to _any_ day, and honestly for us doing 2 loads a day happens very often - it's not an edge case for us. If you're befuddled as to how that is possible, join the club. As for shifting our day's schedule around electricity rates, good luck bringing that idea up with my wife.
  - Brakenshire 9y ago
    Yeah, but the once a week cases are handled by a connection to the grid, just as at present. The bulk of the necessary time shift is handled by the battery and some other techniques to shift demand, and the rest is balancing contention between households in aggregate, and nudging storage and peaker plants, that is, exactly what currently occurs on the grid. > As for shifting our day's schedule around electricity rates, good luck bringing that idea up with my wife. The electricity costs of washing and drying are significant, could easily be hundreds of dollars a year. If you could save half of that by generally running a programme overnight, lots of people would do it . Not everyone would be able to because of noise, with that number increased by technological developments in software and hardware specialized for that use-case, but a lot of people would. And you wouldn't do it for every wash, only when it was convenient. This already happens over here, I often run my dishwasher overnight when the tariffs are lower, it's good for the environment and saves me money, or when I need it sooner I run it straight away.
    - magduf 9y ago
      >Not everyone would be able to because of noise Then they should get newer appliances. Modern dishwashers are whisper-quiet, and modern front-loading washers are barely audible for most of the cycle. The energy savings on these newer appliances should more than pay for the initial costs pretty quickly.
      - photojosh 9y ago
        > Modern dishwashers are whisper-quiet No kidding. Our 2006 dishwasher wasn't too bad, but we just got a 2nd-hand 2016 Bosch and you can watch a movie while it's running.
    - coryfklein 9y ago
      As I said, for us it's not an edge case, but the norm. May not be 2 loads every day, but if I had to guess I'd say that happens about every other day.
      - antisthenes 9y ago
        It's not an edge case for you. I assure you, the vast, overwhelming majority of households can go a workweek without using washer/dryer.
    - photojosh 9y ago
      Nothing to do with solar (yet), but I have time-of-use charges here in Australia, where it was 11¢/kwh 10pm-7am, 30¢ shoulder and 45¢ 2-8pm. So you bet I only started the dryer and dishwasher after 10pm (or when I get up at 6am). We often had 2 loads of washing a day too; when you're night-time toilet training the kids it's a killer. Fortunately we're past that; now it's just loads of school and sports clothes, still not as much.
  - perilunar 9y ago
    You live in Texas and you dry your clothes using an electric dryer? Use a clothes line - they're solar powered.
rnosov 9y ago
Is it that hot in your area that you have to run air conditioner for 3-4 hours after sunset? Typically solar output correlates really nicely with the need for air conditioning. Washing and drying could be done say on a weekend ( during daylight hours ). Many water heaters come with an integrated storage tank for hot water so they can actually be used as a form of energy storage. That leaves lights in your example and yes battery like powerwall will be more than enough to power modern energy efficient lighting and electronics overnight.
- coryfklein 9y ago
  The hottest time of day is 3:00 PM and, due to heat-lag, the hottest time of day _inside_ a house is a little bit after that. Since I set the thermostat higher while I'm gone during the day, this means the house can be roasting by the time I return and require 3-4 hours of AC for it to get more manageable. And no, our washing and drying can not be done on a weekend. We have 3 kids and if we waited for a weekend to do our laundry then that is the only thing we'd be doing all Saturday long.
  - rnosov 9y ago
    In such case you might want to use this thermal lag to your advantage. Set AC to cool your house as much as possible during the midday and you'll come back to hopefully much cooler house in the evening ( so no need to run air conditioner ). Here essentially you would be using the thermal mass of your entire house as an energy storage medium. With washing, if you have to do it every day you might want to start it right after the sunrise when you're likely to to leave for work. If your kids are old enough you can instruct them to take the washing out and put into a dryer as soon as they get home. The point is you'll need to make some changes to your lifestyle and habits but these changes are not as severe and problematic as some people claim.
  - QuotedForTruth 9y ago
    "Since I set the thermostat higher while I'm gone during the day" Aren't you looking for a way to store excess solar power generated during the day? Use it to cool your house! If your house is at 68 when the sun goes down and power generation stops, you may very well be fine without AC until the morning. Use the power when its generated and you don't need as big of a battery to store it for later use.
IpV8 9y ago
You're going to be closer to $10,000 for that kind of storage. Probably not economical for your use case unless you get good rebates and electricity is expensive where you live. Source: I build home battery backup systems for a living. The types of people buying batteries today live in places where arbitrage is an option (california, hawaii), or where the grid is frequently or always down (puerto rico)... or rich people who want to be energy independent. They generally haven't made it to the general public yet, but cost is coming down every year and utilities/incentive programs are spreading.
- dmix 9y ago
  Do you believe the batteries should be subsidized instead of the power going back into the grid?
  - IpV8 9y ago
    Not sure why that's an either or? Do you believe the batteries should be subsidized - Yes, I think that they should be subsidized now. I normally don't like government involvement in markets other than protecting against externalities, but in this case I believe that subsidies can expedite innovation in the area. Once the market exists and the technology moves far enough along, I think that we will be able to slowly remove the subsidies and battery systems will be cheap enough to warrant their place in the market without. Also I strongly believe that the faster we move away from fossil fuels, the less lives will be lost to climate change. instead of the power going back into the grid - Not sure what you mean here. People sell back to the grid all the time. A battery backup system in sell mode is essentially another power plant. Great!
- Retric 9y ago
  $10,000 is ~ 50kwh of battery power, that's vastly more than most people are using over a few hours.
  - philipkglass 9y ago
    As of yet there is nowhere in the world where the installed cost of a 50 kWh hour battery system is only $10,000. I don't think you can even get that much storage for that little money even if you're qualified to install it yourself and are just paying for the hardware. Are you perhaps just looking at wholesale cell costs?
Retric 9y ago
Let's say you spend 10c/kwh and your electric bill is 100$/month. That's 33kwh / day. Let's assume you need 1/3 of that to cover the evening, and batteries cost 200$/kwh and last 10 years that's 2,200$ / 120month ~= 18$/month. That's about the ballpark we are talking about though actual numbers will be different.
pkulak 8y ago
The point is to shift how much power you generated for several off-peak hours to the on-peak hours, not to be totally energy independent for some allotted time. For example, say you can store up 10 kWh of excess energy during the noon sun when it's worthless. If peak is from 5 to 9, you only need a 10 kWh pack that can discharge in 4 hours.

antisthenes 9y ago

It would be more efficient to cool the home while you're not there than to turn on AC immediately after you come home from work in a hot home. > run 2 loads through my washer and dryer (cause I have 3 kids) Surely you don't run 2 loads through your washer and dryer _EVERY_ day, do you? Do your children change clothes every 2 hours? Do you change bedding and towels every day? Point being, I can come up with incredibly inefficient and wasteful scenarios too and then say "well, it doesn't serve my needs either, see!" Shifting energy usage patterns is just as much part of being green as is generating energy in a renewable way. Just because you can come up with a scenario that isn't 100% addressed by that, doesn't mean it's not worth doing in aggregate.

coryfklein 9y ago
> Surely you don't run 2 loads through your washer and dryer _EVERY_ day, do you? No, but I need to be able to _any_ day, and honestly for us doing 2 loads a day happens very often - it's not an edge case for us. If you're befuddled as to how that is possible, join the club. As for shifting our day's schedule around electricity rates, good luck bringing that idea up with my wife.
- Brakenshire 9y ago
  Yeah, but the once a week cases are handled by a connection to the grid, just as at present. The bulk of the necessary time shift is handled by the battery and some other techniques to shift demand, and the rest is balancing contention between households in aggregate, and nudging storage and peaker plants, that is, exactly what currently occurs on the grid. > As for shifting our day's schedule around electricity rates, good luck bringing that idea up with my wife. The electricity costs of washing and drying are significant, could easily be hundreds of dollars a year. If you could save half of that by generally running a programme overnight, lots of people would do it . Not everyone would be able to because of noise, with that number increased by technological developments in software and hardware specialized for that use-case, but a lot of people would. And you wouldn't do it for every wash, only when it was convenient. This already happens over here, I often run my dishwasher overnight when the tariffs are lower, it's good for the environment and saves me money, or when I need it sooner I run it straight away.
  - magduf 9y ago
    >Not everyone would be able to because of noise Then they should get newer appliances. Modern dishwashers are whisper-quiet, and modern front-loading washers are barely audible for most of the cycle. The energy savings on these newer appliances should more than pay for the initial costs pretty quickly.
    - photojosh 9y ago
      > Modern dishwashers are whisper-quiet No kidding. Our 2006 dishwasher wasn't too bad, but we just got a 2nd-hand 2016 Bosch and you can watch a movie while it's running.
  - coryfklein 9y ago
    As I said, for us it's not an edge case, but the norm. May not be 2 loads every day, but if I had to guess I'd say that happens about every other day.
    - antisthenes 9y ago
      It's not an edge case for you. I assure you, the vast, overwhelming majority of households can go a workweek without using washer/dryer.
  - photojosh 9y ago
    Nothing to do with solar (yet), but I have time-of-use charges here in Australia, where it was 11¢/kwh 10pm-7am, 30¢ shoulder and 45¢ 2-8pm. So you bet I only started the dryer and dishwasher after 10pm (or when I get up at 6am). We often had 2 loads of washing a day too; when you're night-time toilet training the kids it's a killer. Fortunately we're past that; now it's just loads of school and sports clothes, still not as much.
- perilunar 9y ago
  You live in Texas and you dry your clothes using an electric dryer? Use a clothes line - they're solar powered.

rnosov 9y ago

Is it that hot in your area that you have to run air conditioner for 3-4 hours after sunset? Typically solar output correlates really nicely with the need for air conditioning. Washing and drying could be done say on a weekend ( during daylight hours ). Many water heaters come with an integrated storage tank for hot water so they can actually be used as a form of energy storage. That leaves lights in your example and yes battery like powerwall will be more than enough to power modern energy efficient lighting and electronics overnight.

coryfklein 9y ago
The hottest time of day is 3:00 PM and, due to heat-lag, the hottest time of day _inside_ a house is a little bit after that. Since I set the thermostat higher while I'm gone during the day, this means the house can be roasting by the time I return and require 3-4 hours of AC for it to get more manageable. And no, our washing and drying can not be done on a weekend. We have 3 kids and if we waited for a weekend to do our laundry then that is the only thing we'd be doing all Saturday long.
- rnosov 9y ago
  In such case you might want to use this thermal lag to your advantage. Set AC to cool your house as much as possible during the midday and you'll come back to hopefully much cooler house in the evening ( so no need to run air conditioner ). Here essentially you would be using the thermal mass of your entire house as an energy storage medium. With washing, if you have to do it every day you might want to start it right after the sunrise when you're likely to to leave for work. If your kids are old enough you can instruct them to take the washing out and put into a dryer as soon as they get home. The point is you'll need to make some changes to your lifestyle and habits but these changes are not as severe and problematic as some people claim.
- QuotedForTruth 9y ago
  "Since I set the thermostat higher while I'm gone during the day" Aren't you looking for a way to store excess solar power generated during the day? Use it to cool your house! If your house is at 68 when the sun goes down and power generation stops, you may very well be fine without AC until the morning. Use the power when its generated and you don't need as big of a battery to store it for later use.

IpV8 9y ago

You're going to be closer to $10,000 for that kind of storage. Probably not economical for your use case unless you get good rebates and electricity is expensive where you live. Source: I build home battery backup systems for a living. The types of people buying batteries today live in places where arbitrage is an option (california, hawaii), or where the grid is frequently or always down (puerto rico)... or rich people who want to be energy independent. They generally haven't made it to the general public yet, but cost is coming down every year and utilities/incentive programs are spreading.

dmix 9y ago
Do you believe the batteries should be subsidized instead of the power going back into the grid?
- IpV8 9y ago
  Not sure why that's an either or? Do you believe the batteries should be subsidized - Yes, I think that they should be subsidized now. I normally don't like government involvement in markets other than protecting against externalities, but in this case I believe that subsidies can expedite innovation in the area. Once the market exists and the technology moves far enough along, I think that we will be able to slowly remove the subsidies and battery systems will be cheap enough to warrant their place in the market without. Also I strongly believe that the faster we move away from fossil fuels, the less lives will be lost to climate change. instead of the power going back into the grid - Not sure what you mean here. People sell back to the grid all the time. A battery backup system in sell mode is essentially another power plant. Great!
Retric 9y ago
$10,000 is ~ 50kwh of battery power, that's vastly more than most people are using over a few hours.
- philipkglass 9y ago
  As of yet there is nowhere in the world where the installed cost of a 50 kWh hour battery system is only $10,000. I don't think you can even get that much storage for that little money even if you're qualified to install it yourself and are just paying for the hardware. Are you perhaps just looking at wholesale cell costs?

Retric 9y ago

Let's say you spend 10c/kwh and your electric bill is 100$/month. That's 33kwh / day. Let's assume you need 1/3 of that to cover the evening, and batteries cost 200$/kwh and last 10 years that's 2,200$ / 120month ~= 18$/month. That's about the ballpark we are talking about though actual numbers will be different.

pkulak 8y ago

The point is to shift how much power you generated for several off-peak hours to the on-peak hours, not to be totally energy independent for some allotted time. For example, say you can store up 10 kWh of excess energy during the noon sun when it's worthless. If peak is from 5 to 9, you only need a 10 kWh pack that can discharge in 4 hours.