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Environmental issue I'd like to solve

Admiral Beez

Admiral Beez

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Am I the only one who wonders just how much water we waste waiting for the hot taps in our homes to actually dispense hot water. There has to be a better way to get hot water out of my tap without wasting gallons of cold water before it.
 
you can't waste water, only the energy it takes to heat it up and the energy to pump & filtrate it + sewage treatment costs.

try pipe insulation. you can always collect that cold water and use it for something else. of course, this isn't practical for everyone.
 
Germans

In Germany in one place I stayed in you had to put water into a small tank just above the taps for it to heat up, it took a few minutes, and that was your hot water. So, it didn't have to stay heated all the time. I thought that was kind of cool, and of course, being German, it was modern and beautiful too.
 
The latest is tankless instant hot water - heated under the counter or on or in or behind the wall, the moment you request it.

42
 
Pep'rJack said:
What do you mean by this, exactly - could you elaborate a bit?
Click to expand...

i did. you can't waste water but you can waste the electricity used to pump it the the reservoir, electricity & chemicals used to filter it, the electricity used to heat it up, electricity used at the treatment plant, etc.

the water ends up where it came from. what you're wasting is the coal to generate electricity which is used to deliver the water to you and make it drinkable plus the chemicals which were created to treat it which also used electricity at some point to make and not to mention the fuel used to transport those chemicals.

if you wanna nit pick.
 
Not sure I agree prometheus. Water doesn't end up where it started. It gets mixed in with the toxic stew that is our sewage system which then requires extensive processing in order to become 'safe' to release back into the ecosystem.

Instant hot water is one alternative, but from what I hear, it is less efficient than traditional tanked heaters. Insulating hot water pipes is also a good step, but only useful when used with moderate frequency.

I'm not sure how much water is actually wasted in the manner you suggest. It takes my shower less than 20 seconds of flow to heat up (not too important in the grand scheme of things. I could compensate by taking slightly shorter showers), and when washing dishes I use the cold water to compensate for the too-hot hot water that's coming. I think any other time you'd run the tap waiting for hot water is pretty rare.
 
afransen said:
Not sure I agree prometheus. Water doesn't end up where it started. It gets mixed in with the toxic stew that is our sewage system which then requires extensive processing in order to become 'safe' to release back into the ecosystem.
Click to expand...

i mentioned that.
 
Thread topic: less a strictly environmental problem and more a plumbing issue.
 
afransen said:
I'm not sure how much water is actually wasted in the manner you suggest. It takes my shower less than 20 seconds of flow to heat up. I think any other time you'd run the tap waiting for hot water is pretty rare.
Click to expand...
Studies show that the average shower lasts 8.2 minutes and uses 65 litres of water, so that's 0.13 litres per second, meaning that your 20 seconds of wasted flow to reach correct temperature took up over 2.5 litres of water. If you're taking 365 showers a year, that's 949 litres of water you've used just trying to get your water warm.

IMO, the best solution is that the hot water system not gain its necessary operating pressure from the city's cold water tap, and that the hot water not be stored in the house's pipes where it cools. Instead, water should come in from the city, and then be sealed off in the water heating system, and when the hot water is turned on at the tap a signal is sent to the tank to send hot water to that tap, with another signal to mix the water with city cold water just before the tap in order to reach the desired temp. Yes, they'd be a lag in the delivery of hot (or any) water through the hot water tap, but this would be equal to the wait for the cold waste water to turn warm.
 
Beez: Maybe save the cold water that runs in before it turns hot and use it to water your garden or houseplants or whatever. Get your water supply metered if you're a small household ( it'll save you money and encourage thrifty use ).
 
Apologies, prometheus. I thought it was worth emphasizing that purifying wastewater is actually nontrivial and doesn't produce potable water as an end product (so it is possible to 'waste' water in that it can't be reused for human consumption).

Apparently average Canadian household hot water usage is 186 L per day. I would argue that 2.5 L per shower is not all that significant. There are other, more cost efficient ways to reduce water usage (using low-flow toilets that actually work without multiple flushes, front-load clothes washers, using greywater for lawn/garden, faucet aerators). Maybe once these are addressed.

I don't know if you've noticed, but many urinals in mens washrooms use a gallon or more per flush.
 
if all the water from peoples eaves were collected into a system that went to a reservoir where people in lower elevations could have gravity pumped water, imagine how much pumping & filtration we could save.

this water could be used for outdoor purposes like watering plants & lawns, etc. it could be tied into the fire hydrant system.


but creating such a system might waste more energy to implement than it would save in the long run.
 
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