5 ms·

Stupid question time: could this be used in sewage systems or similar to generate energy from us flushing the loo?

manigandham 9y ago
Of course, its just harnessing gravity pulling down water to spin a turbine. There are many cases where energy can be harnessed in daily activities, the biggest issue is the efficiency and cost of doing so. Most plumbing use wouldn't add up to nearly enough energy to offset the construction.
- alexchamberlain 9y ago
  My original question was very nearly: can this be used in guttering? I figured that the non-constant flow would probably make it uneconomical.
  - manigandham 9y ago
    Yes, and the maintenance issues of using that waste flow.
  - rtkwe 9y ago
    It has a more fundamental problem because there's just not that much rain falling on most roofs outside of places with monsoon seasons. Because of this even with cheap efficient energy storage there's just not very much there to harvest.
  - ProblemFactory 9y ago
    Technically yes. But there just isn't enough potential energy in the water falling on a typical house. For example, US average yearly rainfall of 76cm, on a 10m*15m roof, at height of two stories at 5 meters, would give you 1.5kWh of energy per year. That's enough to run the appliances in your home for an hour. You might be in a more rainy location, or have a larger home, but the end result is still insignificantly small.
- sandworm101 9y ago
  The energy in the flush is used to push the sewage down the pipe. Take that momentum away and things start to clog.
agumonkey 9y ago
my first newb reaction: good luck maintaining the turbine :) my second reaction: on tall building there might be enough height difference to actually bother thinking about it.
- jotm 9y ago
  Sounds like regenerative braking... not that hard to maintain if installed properly, either - the only sewage exposed part should be the blades?
  - agumonkey 9y ago
    I don't know, water, shit, toilet paper .. not something I would like a turbine in.
    - gweinberg 9y ago
      Yeah, I think if you're going to try to recover power from sewer water at all, it's probably best to do it downstream of the treatment.
    - antisthenes 9y ago
      It will usually be grey water only, without solid waste. So water from showers and sinks, not from toilets. The only contaminant should be a small amount of soap and maybe a few hairs.
- anotherevan 9y ago
  I remember reading an article a while ago about this being done in high-rise hotels. Could not find my original sources, but a quick google found this article: http://bigthink.com/design-for-good/hydro-power-turning-toilet-wastewater-into-electricity http://bigthink.com/design-for-good/hydro-power-turning-toil...

Of course, its just harnessing gravity pulling down water to spin a turbine. There are many cases where energy can be harnessed in daily activities, the biggest issue is the efficiency and cost of doing so. Most plumbing use wouldn't add up to nearly enough energy to offset the construction.

alexchamberlain 9y ago
My original question was very nearly: can this be used in guttering? I figured that the non-constant flow would probably make it uneconomical.
- manigandham 9y ago
  Yes, and the maintenance issues of using that waste flow.
- rtkwe 9y ago
  It has a more fundamental problem because there's just not that much rain falling on most roofs outside of places with monsoon seasons. Because of this even with cheap efficient energy storage there's just not very much there to harvest.
- ProblemFactory 9y ago
  Technically yes. But there just isn't enough potential energy in the water falling on a typical house. For example, US average yearly rainfall of 76cm, on a 10m*15m roof, at height of two stories at 5 meters, would give you 1.5kWh of energy per year. That's enough to run the appliances in your home for an hour. You might be in a more rainy location, or have a larger home, but the end result is still insignificantly small.
sandworm101 9y ago
The energy in the flush is used to push the sewage down the pipe. Take that momentum away and things start to clog.

agumonkey 9y ago

my first newb reaction: good luck maintaining the turbine :) my second reaction: on tall building there might be enough height difference to actually bother thinking about it.

jotm 9y ago
Sounds like regenerative braking... not that hard to maintain if installed properly, either - the only sewage exposed part should be the blades?
- agumonkey 9y ago
  I don't know, water, shit, toilet paper .. not something I would like a turbine in.
  - gweinberg 9y ago
    Yeah, I think if you're going to try to recover power from sewer water at all, it's probably best to do it downstream of the treatment.
  - antisthenes 9y ago
    It will usually be grey water only, without solid waste. So water from showers and sinks, not from toilets. The only contaminant should be a small amount of soap and maybe a few hairs.
anotherevan 9y ago
I remember reading an article a while ago about this being done in high-rise hotels. Could not find my original sources, but a quick google found this article: http://bigthink.com/design-for-good/hydro-power-turning-toilet-wastewater-into-electricity http://bigthink.com/design-for-good/hydro-power-turning-toil...