4 ms·

Your solution simply moves the heat into the wastewater system. What's the impact on sewers if we start filling them with much warmer water?

hwillis 9y ago
It might reduce the buildup of sediment inside pipes. It also might increase pipe erosion. It would probably have a comparable ground-warming effect to geothermal sinking. I have no idea what effect it would have on wastewater treatment plants, but it would cause significant warming local to sewage outflows similar to how water-cooled power plants can disturb river ecosystems. It would probably make sewage maintenance much more difficult since it would be so hot and humid. It might drive out animals living in the sewers, or just make it impossible for them to survive. I have no idea what that would mean. Mainly I was thinking that it would be a great deal easier to simply deal with the heat at the wastewater plant, but there would also be an immense heat sinking effect because of all the distance traveled inside sewers. I was only thinking of it in context of using the ground to sink heat, not as a real implementable plan. I think it goes without saying that the heat-pump-as-a-water-heater idea is far more pragmatic.
krrrh 9y ago
You can actually recover heat from sewers which can heat water or space in nearby buildings. The first example of this (in North America at least) went online in Vancouver around 2010[1]. > Similar to a geo-exchange (or geothermal) system, heat pumps transfer thermal energy from the warm sewage supply to a higher temperature range that’s effective for residential space heating and domestic hot water. While similar in concept, sewage heat recovery is more efficient and cost effective than typical geo-exchange systems. The heat source (raw sewage) has a higher temperature than ground-source heat (on average 18 degrees Celsius as opposed to 8), so it requires less energy to upgrade. Secondly, accessing the sewer line is less invasive and less capital cost intensive than drilling into the earth to access geothermal heat. It also utilizes a continuous supply of waste heat, closing the loop on a fundamental energy >> waste >> energy stream. [2] [1] http://greenbuildingaudiotour.com/buildings/sefc_neighbourhood_energy_utility http://greenbuildingaudiotour.com/buildings/sefc_neighbourho... [2] http://www.thechallengeseries.ca/chapter-05/neighbourhood-energy-utility/#sewer http://www.thechallengeseries.ca/chapter-05/neighbourhood-en...

hwillis 9y ago

It might reduce the buildup of sediment inside pipes. It also might increase pipe erosion. It would probably have a comparable ground-warming effect to geothermal sinking. I have no idea what effect it would have on wastewater treatment plants, but it would cause significant warming local to sewage outflows similar to how water-cooled power plants can disturb river ecosystems. It would probably make sewage maintenance much more difficult since it would be so hot and humid. It might drive out animals living in the sewers, or just make it impossible for them to survive. I have no idea what that would mean. Mainly I was thinking that it would be a great deal easier to simply deal with the heat at the wastewater plant, but there would also be an immense heat sinking effect because of all the distance traveled inside sewers. I was only thinking of it in context of using the ground to sink heat, not as a real implementable plan. I think it goes without saying that the heat-pump-as-a-water-heater idea is far more pragmatic.

krrrh 9y ago

You can actually recover heat from sewers which can heat water or space in nearby buildings. The first example of this (in North America at least) went online in Vancouver around 2010[1]. > Similar to a geo-exchange (or geothermal) system, heat pumps transfer thermal energy from the warm sewage supply to a higher temperature range that’s effective for residential space heating and domestic hot water. While similar in concept, sewage heat recovery is more efficient and cost effective than typical geo-exchange systems. The heat source (raw sewage) has a higher temperature than ground-source heat (on average 18 degrees Celsius as opposed to 8), so it requires less energy to upgrade. Secondly, accessing the sewer line is less invasive and less capital cost intensive than drilling into the earth to access geothermal heat. It also utilizes a continuous supply of waste heat, closing the loop on a fundamental energy >> waste >> energy stream. [2] [1] http://greenbuildingaudiotour.com/buildings/sefc_neighbourhood_energy_utility http://greenbuildingaudiotour.com/buildings/sefc_neighbourho... [2] http://www.thechallengeseries.ca/chapter-05/neighbourhood-energy-utility/#sewer http://www.thechallengeseries.ca/chapter-05/neighbourhood-en...