Solar water heating

[meow2222]

Do you mean 1/3 compared to a traditional top loader? Cos ours dont use anywhere near that much.

NT

[Steve Spence]

Yes, 1/3 of the traditional top loader of equivalent size.

[daestrom]

Not between the laundry and the hw heater. Or do you run your piping in a huge loop all the way around the house to every fixture in turn? LOL [sic].

Even with the laundry on the second floor and HW heater in the basement, it would have to be a pretty large house to need 50' of piping between them.

daestrom

[Cosmopolite]

No, but updraft furnaces are more efficient than counterflow, which I have, because I only have a crawl space. ( 100 year old house )

[Solar Flare]

LOL. You forget about the spur runs to other water appliances that are usually split off and contribute to the thermal drain. The other item is the plumbing always goes in 90 degree angles if done by a professional.

Cripes! My laundry tub and HW heater are more than 50' (well, maybe

40') apart the way the crow flies, let alone all the take offs in between. I can fill my machine quarter full of cold before the hot hits the tub. My ensuite bathroom is even worse as it is over top the laundry room and has another 20' of pipe to go.

piping in a

basement, it

[Cosmopolite]

My " Wife's " machine is an old top loader with 4 water levels, 5 wash/rinse temp.settings and 5 time programs. She likes it. ( Canada )

[wmbjk]

Hmm, let's call it 60 feet of 1/2" copper pipe. Which holds .6 Imperial gallon of water, making your washer 2.4 gallons per fill. What model would that be Gymmy Bob?

Wayne

[meow2222]

Dont think ours have used that much since the 1960s, they've come a long way.

NT

[Steve Spence]

Define "that much". These are both under 5 years old. The front loader uses 1/3rd the water and electric that the top loader does.

[meow2222]

what it says above! JC. Shall I requote for you?

why are you repeating yourself anyway? Whats that going to achieve?

[daestrom]

Such splits don't have to be filled with hot water to run the washer. They just present slightly more surface area for cooling. But then, if you insulate the piping properly, this is a minimal affect. Net result is, you just have a slightly larger mass of copper to warm up along the way.

Actually, in my plumbing there are a couple of places where two 45 degree angles, with five feet between them made more sense than a 90 and 7' of pipe. Admittedly this is rare, but that's why they make 45's. So professionals can use them when it makes sense.

Again, your 'take offs in between' don't have to be purged of water. They add very little to the calculation. Less than one extra foot or two thermal mass to warm up..

You have an unusual house if it's 50' as the crow flies between laundry and HW heater. My laundry's on the second floor and I've worked out the length of piping as 27' along the pipe run.

Well, then *your* house is exceptional. Maybe you should do something about it??

daestrom

[daestrom]

Sigh... There you go using that durn 'math' again. Just keeps conflicting with what people just 'know to be true' ;-)

daestrom

[Steve Spence]

because your response did not fit the thread. Trying to get you to clarify so we can make sense of it.

[sylvan butler]

No, that is not correct because you have spent the principle. What you have calcuated is an annual return on invested capital, annual ROIC.

Return on Investment is calculated using Total Return (TR) and Unit Cost (UC):

ROI = (TR - UC) / UC

For example, if you put $1000 (UC) into a certificate returning 6% (ROI) simple interest, after one year you will get back $1060 (TR). So: ( $1060 - $1000 ) / $1000 = 0.06 or 6% ROI.

Since on your solar system you spent the principle... * unit cost (UC) is the price of the system, plus the 6% you do not get * total return (TR) is the savings

Unless the TR (savings) is more than you could have received by investing the money (guaranteed IBonds are paying more than 6% right now), you will never have a positive return on investment.

In the best case, the system will save more than the lost investment compounded every year. And the system will last long enough to return the principle. And then you can start calculating positive ROI.

Or else just buy it to feel good... That's why I have some PV.

sdb