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I always wonder how much saving water and electricity washing dishes actually matters in relation to everything else we do. In the US people run their HVAC basi

I always wonder how much saving water and electricity washing dishes actually matters in relation to everything else we do. In the US people run their HVAC basically 24/7 either heating or cooling for a lot of the year. Our televisions, video game consoles, and computers are giant electric space heaters that run all day long. So what's the proportional burden of warming a few gallons of water? And I do mean warming, because people who wash dishes by hand don't make the water nearly as hot as what dishwashers use.

lathiat 3y ago
(Note: All of this applies to Australia, if it's much different for your country, please share!) The one that pains me is ovens. They are hugely power hungry and here many models have a very tiny amount of insulation (unless you get a "pyrolitic" model that heats up to 500C to burn the oil off, they have better insulation by requirement of that). We have no energy rating for ovens, so no real incentive to improve. The vast majority are also installed by builders when the house is built, so consumers never even make a choice in the first place. You can also imagine that also pushes most builders to the bottom end of the market. I'm also still always surprised how expensive ovens can be for how simple they are. Most of them now also have a fan to run air around the the outside of the unit so it doesn't overheat the cupboard around it (but not all) which is perhaps also a hint at the poor insulation. The cheap builder model I most recently pulled apart had such poor insulation and gaps all around it. Choice's most recent review has running cost per year ranging from $310 to $651 (this is unfortunately behind a paywall): https://www.choice.com.au/home-and-living/kitchen/ovens/review-and-compare/wall-ovens https://www.choice.com.au/home-and-living/kitchen/ovens/revi... "The running costs are calculated based on running the oven at 170°C for one hour, three times per week for 10 years at 30c per kWh. Where available, the fan-forced function is used, otherwise, the fan-assist is used. For models without either function, the top and bottom elements (convection or traditional bake) are used." That's also probably generous since you often run a higher temp and I suspect 200-220C might make a big difference in that cost. It's a good reason to make use of appliances like air fryers (which despite the name are mostly just ovens), they heat a much smaller space and use a lot less power as a result. Unfortunately the ever shrinking house makes storing and using such things increasingly difficult. Microwaves are also only 50% effeceient (a surprise I recently learnt). I know why we don't have it, and energy ratings are partly a proxy for it, but I always wished the average consumer had easy ways to be more informed about trade-offs exactly like this article talks about. You can trade energy effeciency for a slower cycle - that's partly why most washers these days have many different cycle options - you're trading one thing for another - but most of the time they just tell you the name of the situation they are supposedly for without even a hint at maybe how much more or less energy or water or delicacy you are trading off. The same reason product reviews are never clear cut because everyone has different priorities :)
- eru 3y ago
  > We have no energy rating for ovens, so no real incentive to improve. If energy prices reflect externalities, you wouldn't need any special regulations or official ratings to give people incentives to get improved appliances. Energy costs are already giving people incentives to do so, but perhaps they aren't high enough?
  - Qwertious 3y ago
    Energy ratings inform the customer when they're buying; without them, customers often aren't even aware of their energy use before they buy and install the oven, let alone the comparative efficiency of each oven.
    - eru 3y ago
      And if energy was more expensive, people would demand energy ratings, or otherwise not buy from that brand.
  - lathiat 3y ago
    That may be true if they at least knew how much energy the oven would use, and, if they actually made the purchasing decision. There is no way to know how much the oven is using. Even noce purchased, most people have no idea how much energy in their home is used by what (they just get a single bill and for an entire 2 months period). Lastly as noted, at least here, the majority are installed by builders and included in a package price - the consumer doesn't choose and most builders don't offer an option. Many more would also be chosen by landlords for those who rent, rather than home owners. Or may have been chosen by the home owner that built the house you then purchased. Thus I would say the number of consumers that directly choose and purchase the oven they use would be a low percentage, and the cost to replace it is high enough to make that unlikely and not have a great payback period.
    - eru 3y ago
      If energy was more expensive, people would care and take this into account when making choices. Eg in Germany people routinely check out how good the insulation on eg the windows is when they choose a place to buy or rent. That's because energy is expensive in Germany, and it gets cold enough in winter that you need to heat. If energy is cheap enough, people can be rationally (!) ignorant about these issues.
Jun8 3y ago
US takes great pains to reduce power use, like the ones mentioned in the article but as you point out HVACs at offices work 24/7 at a very cold temperature, so much so that most people bring jackets to work. Cranking the cold up by 1-2F in hotels and offices will probably be imperceptible, yet may save a tremendous amount of energy.
- koolba 3y ago
  > HVACs at offices work 24/7 at a very cold temperature, so much so that most people bring jackets to work. You can always add clothes. If it’s too hot, there’s only so much you can remove. Particularly in a corporate setting
  - klardotsh 3y ago
    Yep. Offices should basically be as cold as realistically feasible for the group working there, but no colder. Few things make me less productive than being in a hot environment: about 69F/20C is my ideal, and if it has to be either direction from there, it should be colder. Anything over about 74F interior temperature and my ability to do much critical thought is basically gone; I have no real heat tolerance but can deal with cold for ages. This is a huge argument in favor of WFH: fewer/no arguments over office temps, a debate about as old as time itself, and particularly a place where it's going to be extremely difficult to get varied groups of folks to all be comfortable and agree (imagine someone super petite vs someone with a good bit of body mass, or someone who grew up in Norway vs someone from Singapore, or even just guys and gals who statistically tend to have different circulation, fat levels, etc. leading to different preferences in ambient temperature).
    - lowercased 3y ago
      Years ago I worked in a moderately large mostly open-office place. My room (with devs) housed 6. There were two open areas with around 80-100 people in open cubes, then... there was a small hallway closed off with 5 offices - the 'executive' hall. One exec guy would turn the AC on high because there was little circulation over there. He liked it 'cool'. I was on the other side of the open area, in a small office. I'd come in in July, and the thermometer on my digital desk clock said 63f. I could not move my fingers to type efficiently because it was so cold. My fingers ached. I brought in a space heater and was chastised that I was "making a big deal out of nothing". 100+ people were consistently uncomfortable to make sure one person was comfortable. The energy waste had to have been enormous. The days this guy was in it reminded me of working in foodservice, having to stock the walk-in cooler on delivery days. Yes, by afternoon, it was bearable, but 63f was just too cold to work effectively. Dozens of us were impacted, but the one top exec needed his comfort the 3 days a week he was in.
imgabe 3y ago
TV, game consoles, most computers (assuming you aren’t mining Bitcoin or something) are basically a rounding error compared to HVAC, and water heating.
- TheRealDunkirk 3y ago
  It was a lot worse in the 90's, but modern electronic devices sip the juice. I bought a meter to put on an outlet to measure my amperage, and my whole office: Mac, PC, work laptop, cable modem, router, and 1 access point uses 1.5 amps. If I run a AAA game on my PC, it ramps up to about 3a. People who point to electronic energy usage need to leave my clock cycles alone, and either direct their anger towards the world's elite, with their private planes and yachts, or just shut up completely. And Microsoft can suck my nuts with their default settings for power savings. Why would I buy a sports car and let someone keep a software governor on the engine?
ramraj07 3y ago
Washing dishes by hand iirc uses 2-3x more water though.
- CameronNemo 3y ago
  Do you have a source for that? I've always heard it, but... I've also watched a lot of people wash dishes in ways that waste lots of water unnecessarily. I'd be curious how the study was conducted, and if they have video of the study participants washing their dishes.
  - winrid 3y ago
    If you fill the sink you're likely already using more water than the dishwasher.
- sixseven 3y ago
  I have always heard that but I never understood how that's possible. I filled a rice bowl with water and reuse that same water to wet all the dirty dishes before rubbing, then rinse with cold running water from the tap. The majority of the energy used in dishwasher is from heating up the water. If you wash with cold water, you are using less energy than the dish washer.
  - jve 3y ago
    > rinse with cold running water from the tap You'd better rinse with hot water to get the soap away.
  - Izkata 3y ago
    Fill up the sink high enough to submerge cooking pots, that's most if not all the way there. Edit: I just measured my kitchen sink and pot for this, 17x19 and 4 inches high = 5.6 gallons. If I go all the way to the sink's overflow at 6.5 inches high, that's 9 gallons.
  - midoridensha 3y ago
    No, you're not. Water isn't free, and a good dishwasher is more water-efficient than you. Water requires a LOT of energy to pump, so less water means less energy.
pottertheotter 3y ago
In regards to saving water, there can be huge benefits to doing so. I'm on the Utility Board overseeing the municipal utilities for my city (electricity, water, wastewater, trash). Our city is growing rapidly, and expanding a sewage system is extremely expensive. We're a city of ~60k and are spending ~$200mm to expand our wastewater treatment plants. And densification means current sewage lines can't support the buildings that need to be built. More efficient appliances mean less water going through the sewer, and less wastewater that needs to be treated. Which means lower capital expenditures, which eventually come directly out of your pocket.
- Dylan16807 3y ago
  It means something, but if a household uses 300 gallons in a day and 3 are going to the dishwasher, you can only improve that so much. And if even a fraction of people feel the need to pre-rinse or post-rinse, those gains can disappear.
- zo1 3y ago
  Side rant. Convenient how we've created a problem that requires huge infrastructure investment. This was a solved problem with septic tanks, that we could have spent many many multiples of money on improving and making ridiculously fancy with sensors and motors and and and. But alas, government is the Big Job Creator. Got to feed that beast.
  - voiper1 3y ago
    I don't buy this cynical take. The current water treatment plants are much more complicated than a simple septic system which lack economies of scale and can still lead to ground water pollution. Also, we've apparently transitioned from waste water being something that had to be dealt with to an actual asset. It can be cleaned to partial usage (and used for agriculture) or directed to help refill specific aquifers.
  - brightlancer 3y ago
    Septic tanks are great for single family-dwellings, awful for dense apartment buildings, and scale from great -> awful very quickly in between. IOW, wastewater infrastructure is necessary above a certain density. The irony is that wastewater infrastructure is one of the areas where cities often defer maintenance, leading to sewage backups when it rains.
eru 3y ago
> I always wonder how much saving water and electricity washing dishes actually matters in relation to everything else we do. That's always a good concern to have. That's why regulations that restrict consumption for individual appliances or activities are pretty silly. An overall carbon price (and appropriate water price) would be much more rational than individually banning drinking straws and thirsty dishwashers. But that's politics for you.
boringuser2 3y ago
My cynical take is that companies have offloaded the responsibility for being "eco-friendly" on the consumer rather than the companies themselves that use 1000x the energy.

lathiat 3y ago

(Note: All of this applies to Australia, if it's much different for your country, please share!) The one that pains me is ovens. They are hugely power hungry and here many models have a very tiny amount of insulation (unless you get a "pyrolitic" model that heats up to 500C to burn the oil off, they have better insulation by requirement of that). We have no energy rating for ovens, so no real incentive to improve. The vast majority are also installed by builders when the house is built, so consumers never even make a choice in the first place. You can also imagine that also pushes most builders to the bottom end of the market. I'm also still always surprised how expensive ovens can be for how simple they are. Most of them now also have a fan to run air around the the outside of the unit so it doesn't overheat the cupboard around it (but not all) which is perhaps also a hint at the poor insulation. The cheap builder model I most recently pulled apart had such poor insulation and gaps all around it. Choice's most recent review has running cost per year ranging from $310 to $651 (this is unfortunately behind a paywall): https://www.choice.com.au/home-and-living/kitchen/ovens/review-and-compare/wall-ovens https://www.choice.com.au/home-and-living/kitchen/ovens/revi... "The running costs are calculated based on running the oven at 170°C for one hour, three times per week for 10 years at 30c per kWh. Where available, the fan-forced function is used, otherwise, the fan-assist is used. For models without either function, the top and bottom elements (convection or traditional bake) are used." That's also probably generous since you often run a higher temp and I suspect 200-220C might make a big difference in that cost. It's a good reason to make use of appliances like air fryers (which despite the name are mostly just ovens), they heat a much smaller space and use a lot less power as a result. Unfortunately the ever shrinking house makes storing and using such things increasingly difficult. Microwaves are also only 50% effeceient (a surprise I recently learnt). I know why we don't have it, and energy ratings are partly a proxy for it, but I always wished the average consumer had easy ways to be more informed about trade-offs exactly like this article talks about. You can trade energy effeciency for a slower cycle - that's partly why most washers these days have many different cycle options - you're trading one thing for another - but most of the time they just tell you the name of the situation they are supposedly for without even a hint at maybe how much more or less energy or water or delicacy you are trading off. The same reason product reviews are never clear cut because everyone has different priorities :)

eru 3y ago
> We have no energy rating for ovens, so no real incentive to improve. If energy prices reflect externalities, you wouldn't need any special regulations or official ratings to give people incentives to get improved appliances. Energy costs are already giving people incentives to do so, but perhaps they aren't high enough?
- Qwertious 3y ago
  Energy ratings inform the customer when they're buying; without them, customers often aren't even aware of their energy use before they buy and install the oven, let alone the comparative efficiency of each oven.
  - eru 3y ago
    And if energy was more expensive, people would demand energy ratings, or otherwise not buy from that brand.
- lathiat 3y ago
  That may be true if they at least knew how much energy the oven would use, and, if they actually made the purchasing decision. There is no way to know how much the oven is using. Even noce purchased, most people have no idea how much energy in their home is used by what (they just get a single bill and for an entire 2 months period). Lastly as noted, at least here, the majority are installed by builders and included in a package price - the consumer doesn't choose and most builders don't offer an option. Many more would also be chosen by landlords for those who rent, rather than home owners. Or may have been chosen by the home owner that built the house you then purchased. Thus I would say the number of consumers that directly choose and purchase the oven they use would be a low percentage, and the cost to replace it is high enough to make that unlikely and not have a great payback period.
  - eru 3y ago
    If energy was more expensive, people would care and take this into account when making choices. Eg in Germany people routinely check out how good the insulation on eg the windows is when they choose a place to buy or rent. That's because energy is expensive in Germany, and it gets cold enough in winter that you need to heat. If energy is cheap enough, people can be rationally (!) ignorant about these issues.

Jun8 3y ago

US takes great pains to reduce power use, like the ones mentioned in the article but as you point out HVACs at offices work 24/7 at a very cold temperature, so much so that most people bring jackets to work. Cranking the cold up by 1-2F in hotels and offices will probably be imperceptible, yet may save a tremendous amount of energy.

koolba 3y ago
> HVACs at offices work 24/7 at a very cold temperature, so much so that most people bring jackets to work. You can always add clothes. If it’s too hot, there’s only so much you can remove. Particularly in a corporate setting
- klardotsh 3y ago
  Yep. Offices should basically be as cold as realistically feasible for the group working there, but no colder. Few things make me less productive than being in a hot environment: about 69F/20C is my ideal, and if it has to be either direction from there, it should be colder. Anything over about 74F interior temperature and my ability to do much critical thought is basically gone; I have no real heat tolerance but can deal with cold for ages. This is a huge argument in favor of WFH: fewer/no arguments over office temps, a debate about as old as time itself, and particularly a place where it's going to be extremely difficult to get varied groups of folks to all be comfortable and agree (imagine someone super petite vs someone with a good bit of body mass, or someone who grew up in Norway vs someone from Singapore, or even just guys and gals who statistically tend to have different circulation, fat levels, etc. leading to different preferences in ambient temperature).
  - lowercased 3y ago
    Years ago I worked in a moderately large mostly open-office place. My room (with devs) housed 6. There were two open areas with around 80-100 people in open cubes, then... there was a small hallway closed off with 5 offices - the 'executive' hall. One exec guy would turn the AC on high because there was little circulation over there. He liked it 'cool'. I was on the other side of the open area, in a small office. I'd come in in July, and the thermometer on my digital desk clock said 63f. I could not move my fingers to type efficiently because it was so cold. My fingers ached. I brought in a space heater and was chastised that I was "making a big deal out of nothing". 100+ people were consistently uncomfortable to make sure one person was comfortable. The energy waste had to have been enormous. The days this guy was in it reminded me of working in foodservice, having to stock the walk-in cooler on delivery days. Yes, by afternoon, it was bearable, but 63f was just too cold to work effectively. Dozens of us were impacted, but the one top exec needed his comfort the 3 days a week he was in.

imgabe 3y ago

TV, game consoles, most computers (assuming you aren’t mining Bitcoin or something) are basically a rounding error compared to HVAC, and water heating.

TheRealDunkirk 3y ago
It was a lot worse in the 90's, but modern electronic devices sip the juice. I bought a meter to put on an outlet to measure my amperage, and my whole office: Mac, PC, work laptop, cable modem, router, and 1 access point uses 1.5 amps. If I run a AAA game on my PC, it ramps up to about 3a. People who point to electronic energy usage need to leave my clock cycles alone, and either direct their anger towards the world's elite, with their private planes and yachts, or just shut up completely. And Microsoft can suck my nuts with their default settings for power savings. Why would I buy a sports car and let someone keep a software governor on the engine?

ramraj07 3y ago

Washing dishes by hand iirc uses 2-3x more water though.

CameronNemo 3y ago
Do you have a source for that? I've always heard it, but... I've also watched a lot of people wash dishes in ways that waste lots of water unnecessarily. I'd be curious how the study was conducted, and if they have video of the study participants washing their dishes.
- winrid 3y ago
  If you fill the sink you're likely already using more water than the dishwasher.
sixseven 3y ago
I have always heard that but I never understood how that's possible. I filled a rice bowl with water and reuse that same water to wet all the dirty dishes before rubbing, then rinse with cold running water from the tap. The majority of the energy used in dishwasher is from heating up the water. If you wash with cold water, you are using less energy than the dish washer.
- jve 3y ago
  > rinse with cold running water from the tap You'd better rinse with hot water to get the soap away.
- Izkata 3y ago
  Fill up the sink high enough to submerge cooking pots, that's most if not all the way there. Edit: I just measured my kitchen sink and pot for this, 17x19 and 4 inches high = 5.6 gallons. If I go all the way to the sink's overflow at 6.5 inches high, that's 9 gallons.
- midoridensha 3y ago
  No, you're not. Water isn't free, and a good dishwasher is more water-efficient than you. Water requires a LOT of energy to pump, so less water means less energy.

pottertheotter 3y ago

In regards to saving water, there can be huge benefits to doing so. I'm on the Utility Board overseeing the municipal utilities for my city (electricity, water, wastewater, trash). Our city is growing rapidly, and expanding a sewage system is extremely expensive. We're a city of ~60k and are spending ~$200mm to expand our wastewater treatment plants. And densification means current sewage lines can't support the buildings that need to be built. More efficient appliances mean less water going through the sewer, and less wastewater that needs to be treated. Which means lower capital expenditures, which eventually come directly out of your pocket.

Dylan16807 3y ago
It means something, but if a household uses 300 gallons in a day and 3 are going to the dishwasher, you can only improve that so much. And if even a fraction of people feel the need to pre-rinse or post-rinse, those gains can disappear.
zo1 3y ago
Side rant. Convenient how we've created a problem that requires huge infrastructure investment. This was a solved problem with septic tanks, that we could have spent many many multiples of money on improving and making ridiculously fancy with sensors and motors and and and. But alas, government is the Big Job Creator. Got to feed that beast.
- voiper1 3y ago
  I don't buy this cynical take. The current water treatment plants are much more complicated than a simple septic system which lack economies of scale and can still lead to ground water pollution. Also, we've apparently transitioned from waste water being something that had to be dealt with to an actual asset. It can be cleaned to partial usage (and used for agriculture) or directed to help refill specific aquifers.
- brightlancer 3y ago
  Septic tanks are great for single family-dwellings, awful for dense apartment buildings, and scale from great -> awful very quickly in between. IOW, wastewater infrastructure is necessary above a certain density. The irony is that wastewater infrastructure is one of the areas where cities often defer maintenance, leading to sewage backups when it rains.

eru 3y ago

> I always wonder how much saving water and electricity washing dishes actually matters in relation to everything else we do. That's always a good concern to have. That's why regulations that restrict consumption for individual appliances or activities are pretty silly. An overall carbon price (and appropriate water price) would be much more rational than individually banning drinking straws and thirsty dishwashers. But that's politics for you.

boringuser2 3y ago

My cynical take is that companies have offloaded the responsibility for being "eco-friendly" on the consumer rather than the companies themselves that use 1000x the energy.