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28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

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Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#131

Post by imzadi »

tetha wrote: post #36
out_of_protocol wrote: post #15

Earlier quoted context omitted.

> too many problems for wildlife There were a meta-analysis regarding population of birds in areas with/without wind turbines, found no statistically significant difference (unlike coal, where difference was huge)

Yep. I mostly meant for or rather caused by this kite. I wouldn't expect it intuitively, as it's just a big object in the water, not moving erratically or obstructing anything.

It has a 39-foot wingspan and moves in a figure 8 pattern on a seabed tether. There's going to be at least some implication for local wildlife, but is it worse than the impacts of fossil fuels? I have no idea. It's definitely an interesting concept. I'm sure it will get more efficient and require a smaller footprint over time, assuming we invest in it.

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#132

Post by bagels »

kevinbowman wrote: post #65
debok wrote: post #55

Earlier quoted context omitted.

A kettle uses ~1.5KW, a geyser ~2KW, an oven ~5KW, a stove about ~3KW. These are fairly high estimates I got from some quick googling. If you add these all up, and account for some more appliances (HVAC, fridge/freezer etc.), I think it is safe to estimate that a household less than 20KW at peak, even though it is a fairly high estimate. So going backwards from there, 1.2MW = 1200KW and 1200KW / 20KW = 60 households…

Also relevant, houses aren't boiling a kettle and running their oven 24x7, so this is more like worst-case peak load and will be spread across different houses. Having some kind of battery storage closer to the houses will help a lot - the tidal generator can run fairly constantly and fill the battery, and the houses can draw in short bursts from the battery.

There is synchronized kettle use and toilet use around televised sports games.

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#133

Post by bagels »

KeplerBoy wrote: post #7
mywacaday wrote: post #4

Earlier quoted context omitted.

I've often thought why not dam a whole estuary or bay and use hydro to collect the energy on the the fall and rise of the tide. I know the environmental impact wouldake it unpalatable but are there any reasons it wouldn't work?

Meet project Atlantropa, a proposed plan to dam the Mediterranean (or more accurately the atlantic ocean) at the strait of Gibraltar. A project so absurd and gigantic it would deserve its own thread really. https://wikipedia.org/wiki/Atlantropa

Meanwhile, Egypt wants to expand the mediterranian: https://en.wikipedia.org/wiki/Qattara_Depression_Project

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#134

Post by rootusrootus »

tetha wrote: post #14

Since the number 1.2MW didn't mean much to me, modern on-shore wind turbines seem to supply 3-4MW and offshore ones 8 - 12MW. But this seems a lot easier to transport and install compared to cranes and the nightmare of navigating turbine blades on trucks through places. And if these hold up to water and don't cause too many problems for wildlife, there would be a lot less discussions about these "messing up my skylin…

> modern on-shore wind turbines seem to supply 3-4MW

That sounds like the very largest of the most recent wind turbines. I think most of the in-production wind turbines people are used to seeing these days are closer to the 2 megawatt range.

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#135

Post by rootusrootus »

aqme28 wrote: post #39
tetha wrote: post #14

Since the number 1.2MW didn't mean much to me, modern on-shore wind turbines seem to supply 3-4MW and offshore ones 8 - 12MW. But this seems a lot easier to transport and install compared to cranes and the nightmare of navigating turbine blades on trucks through places. And if these hold up to water and don't cause too many problems for wildlife, there would be a lot less discussions about these "messing up my skylin…

A common blocker for offshore wind is people* complaining about seeing wind turbines on their formerly immaculate horizon. These don't have that problem. *: e.g. Ted Kennedy. Rich and politically connected people like to live on the coast

What's interesting is that we can stop off-shore wind projects for that reason, but can't seem to stop the advertising barges that run up and down the coastlines.

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#136

Post by Taek »

tzs wrote: post #111
methyl wrote: post #67

Earlier quoted context omitted.

I’m really surprised by this data. In Poland, it’s around 2000 kWh/year, which is 6kWh/day - 5 times less!

According to to stat.gov.pl [1] the average Polish household uses ~24.6 GJ of energy annually per 1 inhabitant. That's 6800 kWh annually per 1 inhabitant. According to eia.gov [2][3] the average US household uses annually 56.6 million BTUs of natural gas and 10500 kWh of electricity. 56.6 million BTUs is 16600 kWh. That would bring the total to 27100 kWh. But wait...the Polish data is per inhabitant. The average numb…

Thanks for breaking this down cleanly and providing sources! Greatly appreciated!

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#137

Post by beefman »

rsynnott wrote: post #127
beefman wrote: post #125

For comparison, electricity was sold to the U.S. grid at about $48/MWh in 2023. This is less than any of the cost projections mentioned in the article. Howabout materials? It says this weighs 28 tons and makes 1.2 MW. That's 21g/W assuming a 100% capacity factor, no balance of plant, and assuming those are short tons. Compare to an iPhone 15, which consumes about 1W per 150g in use. That's a materials intensity multi…

That would benefit from various subsidies; from the article it _looks_ like the $54/MWh projected figure is before subsidy.

Subsidies would be useful in getting it from $108/MWh to $54/MWh faster, but they don't change the underlying physics of the technology.

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#138

Post by rsynnott »

beefman wrote: post #137
rsynnott wrote: post #127

Earlier quoted context omitted.

That would benefit from various subsidies; from the article it _looks_ like the $54/MWh projected figure is before subsidy.

Subsidies would be useful in getting it from $108/MWh to $54/MWh faster, but they don't change the underlying physics of the technology.

Sorry, what I mean is that the $48/MWh figure benefits from significant subsidy; it's not a realistic cost of provision.

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#139

Post by Sammi »

DrNosferatu wrote: post #97
Sammi wrote: post #92

Earlier quoted context omitted.

What type of mechanical wear are you thinking of? I can think of a propeller and generator, but those are solved problems. This is just a boat with a propeller. Only instead of using the generator as an engine to spin the propeller, the tides spin the propeller which generates power in the generator. Steering is also a solved boat problem. Then there's the tether and anchor. This is the reason it swims in a figure 8,…

That swinging tether immersed in saltwater(!) will have to work miracles.

I'm trying to see what prior art we can find on the internet on tethers and anchors used in fish farming and offshore oil industry, but I'm not finding many sources.

Re: 28-ton, 1.2-megawatt tidal kite is now exporting power to the grid

#140

Post by ragebol »

ComputerGuru wrote: post #118
debok wrote: post #55

Earlier quoted context omitted.

A kettle uses ~1.5KW, a geyser ~2KW, an oven ~5KW, a stove about ~3KW. These are fairly high estimates I got from some quick googling. If you add these all up, and account for some more appliances (HVAC, fridge/freezer etc.), I think it is safe to estimate that a household less than 20KW at peak, even though it is a fairly high estimate. So going backwards from there, 1.2MW = 1200KW and 1200KW / 20KW = 60 households…

(What’s a geyser?)

From top of my head: my grandma used to have one. There was always a little flame running for safety in case of leaks, but when she used hoy water, I think the geyser just heated it on the go, instead of preheating a reservoir.

Could be wrong though.

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