4 ms·

Reverse the flow?

by uptown 5y ago

Reverse the flow?

Cthulhu_ 5y ago
Yup, should require only a few adjustments. Over here (NL) they're looking into repurposing the existing natural gas network to transport hydrogen instead. I mean we're years away from removing the use of natural gas entirely, but the idea is there.
- m4rtink 5y ago
  Given how small hydrogen atoms are, causing all kinds of leaks even in purpose built equipment & that hydrogen fires are invisible in sunlight I'm skeptical.
seanmcdirmid 5y ago
Assuming your pipeline or canal is gravity driven, that could be hard.
- lazide 5y ago
  It may also be economically unviable. Phoenix is around 1000 ft AGL, and much of the rest of Arizona that is populated is higher (Tucson 2300, Prescott ~5k, and Flagstaff almost 7k ft above sea level). Someone above was quoting CCF/HCF (Centrum Cubic Feet, or 100ft^3 of water or 748 gallons), which is a customary way to measure water volume in many utilities, and noting ~ $6.89 per CCF I believe. I did some random googling and ran across [https://www.tucsonaz.gov/water/residential-rates-and-monthly-charges https://www.tucsonaz.gov/water/residential-rates-and-monthly...], which shows a connection charge of ~ $12 Which shows that the average Tucson resident seems to be paying less then $5/ccf right now - discounting connection fee- with 'high use' (~ 60 CCF, the top bracket they list), around $10/ccf. 1 ccf being 748 gallons, and each gallon weighing 8.34 lbs means you're getting 6238 lbs of water for less than $5 if you're a typical Tucson resident, and for ~ $10 if you're a high use resident. Lifting water from ~ sea level to the 2300 ft AGL level takes energy (in a conservation of energy sense, regardless of efficiency). Specifically, approx 27,176 joules per gallon (yeah sorry) to lift in this case, or 20,327,648 joules per CCF, or in 'American' raw energy terms 5.65kwh. Properly sized electric motors are around 90 percent efficient, with the best possible about 97%. Large centrifugal pumps, properly sized, can hit up to 93%. Combined, that means in theory we could pump water uphill at, at best, 90% efficiency, and assuming no losses to friction in the pipes (which would be notable over the distances we're talking about, but is too complex to guesstimate here, but feel free to check out https://en.wikipedia.org/wiki/Friction_loss https://en.wikipedia.org/wiki/Friction_loss), So, if we pump in energy at 90% efficiency, we need 7.38 kwh of energy to get that water from sea level to Tucson - not counting cleaning or treating the water, infrastructure maintenance/piping, friction losses moving it over that distance, losses due to leaks, etc. Tucson has cheap electricity by California Standards (my typical price per kwh is ~ $.45, there are a lot of misleading numbers out there), and though I see .12/kwh, CA says .24 and that is blatantly false. Even so, if we use that number .12, it would add $1, literally if all we were doing was taking perfectly great water and just pumping it to Tucson, with no need for pipes, or any other infrastructure. That may not sound like much, but for a typical Tucson resident that would increase their bills by 20%. High users less as a percentage, but still over 10%. When you add in the major infrastructure building and maintenance costs (which probably swamp the energy costs), you're looking at 50% or more increase. If you add in acquisition of drinkable water from somewhere closer than Oregon (which bringing it up and over multiple mountain ranges is going to be fun), also even more of an increase.
  - seanmcdirmid 5y ago
    California electricity is generally cheap in the sense that you don't need to use much of it (the big metro areas with the most people have very mild climates). I imagine AC is important in a place like Tucson. The fact that pumping water uphill is so expensive is why most of the water in the mountain west comes from the Rockies (where it flows down hill), though the exhaustion of the rocky mountain glaciers (due to global warming or whatever one believes is the reason) means that all that water built up over millions of years is coming to an end.

Reverse the flow?

by uptown 5y ago

Reverse the flow?

Yup, should require only a few adjustments. Over here (NL) they're looking into repurposing the existing natural gas network to transport hydrogen instead. I mean we're years away from removing the use of natural gas entirely, but the idea is there.

m4rtink 5y ago
Given how small hydrogen atoms are, causing all kinds of leaks even in purpose built equipment & that hydrogen fires are invisible in sunlight I'm skeptical.

seanmcdirmid 5y ago

Assuming your pipeline or canal is gravity driven, that could be hard.

lazide 5y ago
It may also be economically unviable. Phoenix is around 1000 ft AGL, and much of the rest of Arizona that is populated is higher (Tucson 2300, Prescott ~5k, and Flagstaff almost 7k ft above sea level). Someone above was quoting CCF/HCF (Centrum Cubic Feet, or 100ft^3 of water or 748 gallons), which is a customary way to measure water volume in many utilities, and noting ~ $6.89 per CCF I believe. I did some random googling and ran across [https://www.tucsonaz.gov/water/residential-rates-and-monthly-charges https://www.tucsonaz.gov/water/residential-rates-and-monthly...], which shows a connection charge of ~ $12 Which shows that the average Tucson resident seems to be paying less then $5/ccf right now - discounting connection fee- with 'high use' (~ 60 CCF, the top bracket they list), around $10/ccf. 1 ccf being 748 gallons, and each gallon weighing 8.34 lbs means you're getting 6238 lbs of water for less than $5 if you're a typical Tucson resident, and for ~ $10 if you're a high use resident. Lifting water from ~ sea level to the 2300 ft AGL level takes energy (in a conservation of energy sense, regardless of efficiency). Specifically, approx 27,176 joules per gallon (yeah sorry) to lift in this case, or 20,327,648 joules per CCF, or in 'American' raw energy terms 5.65kwh. Properly sized electric motors are around 90 percent efficient, with the best possible about 97%. Large centrifugal pumps, properly sized, can hit up to 93%. Combined, that means in theory we could pump water uphill at, at best, 90% efficiency, and assuming no losses to friction in the pipes (which would be notable over the distances we're talking about, but is too complex to guesstimate here, but feel free to check out https://en.wikipedia.org/wiki/Friction_loss https://en.wikipedia.org/wiki/Friction_loss), So, if we pump in energy at 90% efficiency, we need 7.38 kwh of energy to get that water from sea level to Tucson - not counting cleaning or treating the water, infrastructure maintenance/piping, friction losses moving it over that distance, losses due to leaks, etc. Tucson has cheap electricity by California Standards (my typical price per kwh is ~ $.45, there are a lot of misleading numbers out there), and though I see .12/kwh, CA says .24 and that is blatantly false. Even so, if we use that number .12, it would add $1, literally if all we were doing was taking perfectly great water and just pumping it to Tucson, with no need for pipes, or any other infrastructure. That may not sound like much, but for a typical Tucson resident that would increase their bills by 20%. High users less as a percentage, but still over 10%. When you add in the major infrastructure building and maintenance costs (which probably swamp the energy costs), you're looking at 50% or more increase. If you add in acquisition of drinkable water from somewhere closer than Oregon (which bringing it up and over multiple mountain ranges is going to be fun), also even more of an increase.
- seanmcdirmid 5y ago
  California electricity is generally cheap in the sense that you don't need to use much of it (the big metro areas with the most people have very mild climates). I imagine AC is important in a place like Tucson. The fact that pumping water uphill is so expensive is why most of the water in the mountain west comes from the Rockies (where it flows down hill), though the exhaustion of the rocky mountain glaciers (due to global warming or whatever one believes is the reason) means that all that water built up over millions of years is coming to an end.