5 ms·

Which source are you using for that number?

dmurray 7y ago
The numbers quoted for the Queensland plant referenced above would translate to about A$1.50, or US$1, for a thousand gallons. (10c/kWh for electricity according to [0]) There are running costs other than electricity, but it's always talked about as being power-intensive, so it seems fair to assume the cost of electricity dominates. $1 for a thousand gallons seems like a non issue for domestic use in developed countries. It's on par with the cheapest rates consumers currently pay in Europe, while some countries pay 8x more [1]. Even in most poor countries it should be attainable. [0]https://www.aemc.gov.au/energy-system/electricity/electricity-market/spot-and-contract-markets https://www.aemc.gov.au/energy-system/electricity/electricit... [1]https://www.thejournal.ie/water-charges-in-ireland-versus-europe-1789576-Nov2014/ https://www.thejournal.ie/water-charges-in-ireland-versus-eu...
Retric 7y ago
Several sources list 3$ as the lowest all inclusive price. Though notability these systems are much more costly when run intermittently. https://www.advisian.com/en-us/global-perspectives/the-cost-of-desalination https://www.advisian.com/en-us/global-perspectives/the-cost-... The issue is just keeping them on standby is expensive. So, if you only need one for 6 months every 3 years you end up paying a lot more per m3 of water.
- thaumaturgy 7y ago
  Hmm. That link seems to use a paper for its source, titled "Technical review and evaluation of the economics of water desalination: Current and future challenges for better water supply sustainability". I tracked down a copy of that paper. It opens with: "The cost of desalinated seawater has fallen below US$0.50/m3 for a large scale seawater reverse osmosis plant at a specific location and conditions while in other locations the cost is 50% higher (US$1.00/m3) for a similar facility. In addition to capital and operating costs, other parameters such as local incentives or subsidies may also contribute to the large difference in desalted water cost between regions and facilities. Plant suppliers and consultants have their own cost calculation methodologies, but they are confidential and provide water costs with different accuracies. The few existing costing methodologies and software packages such as WTCost© and DEEP provide an estimated cost with different accuracies and their applications are limited to specific conditions. Most of the available cost estimation tools are of the black box type, which provide few details concerning the parameters and methodologies applied for local conditions." I read through the rest of it. To the extent that it offers cost comparisons of some large scale SWRO projects, they seem to be self-reported and come from projects in Saudi Arabia, Israel, Oman, and Australia. This leads me to a couple of concerns WRT the construction and operating costs of SWRO projects: (a) that a comprehensive, independent, apples-to-apples accounting of the costs of these projects has not yet been done; (b) that some of the long-term costs are being externalized, especially the expected impacts on local ecological systems that become the necessary dumping grounds for the wastewater; (c) that the costs to date are severely location-specific, and do not address for instance trying to transport seawater a mile uphill as needed in many of the areas expected to or currently experiencing severe freshwater instability. Clearly SWRO is a viable option in specific areas that have nearby access to a suitable water source, good power infrastructure (or solar availability), a lack of freshwater availability, and an appropriate wastewater treatment strategy (or, more likely -- and sadly -- loose regulations that obviate the need to address this). But calls for SWRO as a worldwide, one-size-fits-all, cheap solution are misguided and misinformed, IMO. Mostly I worry that "just build desal" will frustrate efforts for conservation and improving existing infrastructure, especially in places where desal isn't a viable option anyway.
  - deleted 7y ago
    [deleted]
  - Retric 7y ago
    A cubic meter of water is 264.17 gallons. So, 50c per gallon is ~2$ per 1000 gallons. 50% more is 0.75$ per cubic meter (not 1$) or 3$ per 1000 gallons. Though if it’s 100% more that’s 4$ per 1,000 gallons. That paper is also from 2012, but I generally agree with your conclusions.

The numbers quoted for the Queensland plant referenced above would translate to about A$1.50, or US$1, for a thousand gallons. (10c/kWh for electricity according to [0]) There are running costs other than electricity, but it's always talked about as being power-intensive, so it seems fair to assume the cost of electricity dominates. $1 for a thousand gallons seems like a non issue for domestic use in developed countries. It's on par with the cheapest rates consumers currently pay in Europe, while some countries pay 8x more [1]. Even in most poor countries it should be attainable. [0]https://www.aemc.gov.au/energy-system/electricity/electricity-market/spot-and-contract-markets https://www.aemc.gov.au/energy-system/electricity/electricit... [1]https://www.thejournal.ie/water-charges-in-ireland-versus-europe-1789576-Nov2014/ https://www.thejournal.ie/water-charges-in-ireland-versus-eu...

Retric 7y ago

Several sources list 3$ as the lowest all inclusive price. Though notability these systems are much more costly when run intermittently. https://www.advisian.com/en-us/global-perspectives/the-cost-of-desalination https://www.advisian.com/en-us/global-perspectives/the-cost-... The issue is just keeping them on standby is expensive. So, if you only need one for 6 months every 3 years you end up paying a lot more per m3 of water.

thaumaturgy 7y ago
Hmm. That link seems to use a paper for its source, titled "Technical review and evaluation of the economics of water desalination: Current and future challenges for better water supply sustainability". I tracked down a copy of that paper. It opens with: "The cost of desalinated seawater has fallen below US$0.50/m3 for a large scale seawater reverse osmosis plant at a specific location and conditions while in other locations the cost is 50% higher (US$1.00/m3) for a similar facility. In addition to capital and operating costs, other parameters such as local incentives or subsidies may also contribute to the large difference in desalted water cost between regions and facilities. Plant suppliers and consultants have their own cost calculation methodologies, but they are confidential and provide water costs with different accuracies. The few existing costing methodologies and software packages such as WTCost© and DEEP provide an estimated cost with different accuracies and their applications are limited to specific conditions. Most of the available cost estimation tools are of the black box type, which provide few details concerning the parameters and methodologies applied for local conditions." I read through the rest of it. To the extent that it offers cost comparisons of some large scale SWRO projects, they seem to be self-reported and come from projects in Saudi Arabia, Israel, Oman, and Australia. This leads me to a couple of concerns WRT the construction and operating costs of SWRO projects: (a) that a comprehensive, independent, apples-to-apples accounting of the costs of these projects has not yet been done; (b) that some of the long-term costs are being externalized, especially the expected impacts on local ecological systems that become the necessary dumping grounds for the wastewater; (c) that the costs to date are severely location-specific, and do not address for instance trying to transport seawater a mile uphill as needed in many of the areas expected to or currently experiencing severe freshwater instability. Clearly SWRO is a viable option in specific areas that have nearby access to a suitable water source, good power infrastructure (or solar availability), a lack of freshwater availability, and an appropriate wastewater treatment strategy (or, more likely -- and sadly -- loose regulations that obviate the need to address this). But calls for SWRO as a worldwide, one-size-fits-all, cheap solution are misguided and misinformed, IMO. Mostly I worry that "just build desal" will frustrate efforts for conservation and improving existing infrastructure, especially in places where desal isn't a viable option anyway.
- deleted 7y ago
  [deleted]
- Retric 7y ago
  A cubic meter of water is 264.17 gallons. So, 50c per gallon is ~2$ per 1000 gallons. 50% more is 0.75$ per cubic meter (not 1$) or 3$ per 1000 gallons. Though if it’s 100% more that’s 4$ per 1,000 gallons. That paper is also from 2012, but I generally agree with your conclusions.