Portland's New Pipes Harvest Power from Drinking Water | Hacker News Reader

Portland's New Pipes Harvest Power from Drinking Water

fastcoexist.com

46 pointssuperfx19 comments

Extracts from the Lucid Energy FAQ [0] ....

How does the system work?

The LucidPipe™ Power System uses the flow of water inside the PWB pipeline to spin four 42” turbines that produce electricity for PGE [Portland General Electric]. PGE purchases the electricity from Conduit 3 as part of their strong commitment to both renewables and local sources of energy.

How much energy will the project generate?

This is a 200 kW nameplate capacity project. The system is expected to generate an average of 1,100 megawatt hours of energy per year, enough electricity to power up to 150 homes.

...

DOE Grant – The U.S. Department of Energy awarded Lucid Energy a phase 1 SBIR grant to field test the LucidPipe technology.

Investors – Lucid Energy has secured private funding from a very active syndicate of investors including Northwest Pipe Company, the Israeli hybrid venture capital/crowdsourcing platform OurCrowd, Star Energy and the Harbourton Fund as well as more than $1 million from the U.S. Department of Energy. The funding is being used to accelerate commercialization of the LucidPipe Power System worldwide

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Notably absent is what percentage of the power revenue Portland gets from the energy generated.

[0] http://www.lucidenergy.com/wp-content/uploads/2015/01/Lucid-...

> 1,100 megawatt hours of energy per year, enough electricity to power up to 150 homes.

That doesn't quite add up, that comes to only 837 watts (average use) per home. For perspective, a microwave oven uses 1500 watts while it's on. A rough estimate for a central AC system is 3500 watts. http://www.senicaair.com/blog/how-many-watts-does-an-air-con...

Maybe they don't tend to have central AC in Portland, but electric heating can use even more.

You're not running a microwave all day long, and you don't run much at all at night.

I'm not sure what usage is like in Portland, but where I'm from (outside the USA, but still first world) I'm probably running about 200 W at night, a couple of energy efficient bulbs, and standby power.

During the day, when nobody is home, I probably use about the same. So that leaves about 1800 W for 8 hours a day that you're at home.

Judging roughly by what my power bill is, divided by the hours in the month, I use about that amount of power, at least in summer. This is for an uninsulated house in a temperate climate with 4 students in it.

The power consumption in winter is significantly higher, which is in part due to the fact that 70 year old houses with no insulation at all leak heat like a sieve, and due to regulations, we can only use electric heating.

Central AC pulls 3.5 kW when it's running, but it doesn't run all day long, it only runs for maybe 10 minutes per hour or so, if you have a well insulated house.

837W all day long is 20kWh, almost exactly so I guess that's the figure used. That's roughly double my usage in the UK, and I work from home.

It's ~7300kWh/year, which is a bit lower than the US average of almost 11000kWh (https://www.eia.gov/tools/faqs/faq.cfm?id=97&t=3). In the UK it's an overestimate as we average closer to 4000kWh (chart 3: https://www.gov.uk/government/uploads/system/uploads/attachm...)

For those interested in more details on this project, PBS Newshour had a good report on it in April https://youtu.be/vlbp0VxZG28

I've never understood the concept of something like this. Isn't the energy generated canceled out with power expended to pump it through? I feel like friction would never make something like this useful.

Can someone explain how this kind of generation is beneficial?

Asked the same thing the last time this was posted. There's a good answer: https://news.ycombinator.com/item?id=9835804 (in short, you already have too much pressure being relieved using valves along the way with the extra energy wasted)

This comment explains it pretty well I think.

https://news.ycombinator.com/item?id=9838012

It's the same idea behind regenerative braking.

"The pipes can't generate power in every location; they only work in places where water is naturally flowing downward with gravity (if water is being pumped, the system would waste energy)."

The energy is input by the sun which turns sea water (at sea level) into water vapor, which then moves to higher elevation due to weather patterns (also caused by sun's energy input) and falls as rain into a reservoir at higher elevation than the locations it serves.

All energy on earth is solar energy.

Apart from nuclear power. Even that is technically 'solar' in the sense that the elements necessary were made in a star, but not our sun.

You're right about nuclear (though, if we can get hydrogen fusion to be profitable, that won't even be stellar in the way that fission is).

Tidal energy isn't solar in any sense. It's harvesting momentum which in turn is generated by some combination of gravity and the Big Bang.

Geothermal energy isn't solar. It's harvesting heat, which apparently comes from three sources: heat from the planet's formation, caused by gravity, heat from friction from deep-interior motion, and heat from radioactive decay. Only the last of these is even stellar, and none are solar.

Moon (and Earth) were given their momentum during the formation of the solar system. I'd say that's solar.

And if you want to make a distinction about which star forged the heavy elements required for radioactive decay, then I'll agree it's 'stellar' energy not so much 'solar'.

Salt Lake City is planning a similar project to harness energy from municipal water pipes. From 6 months ago:

https://www.ksl.com/?sid=35603966&nid=148

Previous post: https://news.ycombinator.com/item?id=9835650 (different source)

I've often wondered why someone couldn't invent a home irrigation system that was recharged by the flow/pressure of water passing through.

I hope that this will help lower the insanely high utility bills that Portland residents have to pay.

More likely it's going to raise your utility bill, Portland has to pay for our fancy new pipes somehow.

Reply on news.ycombinator.com