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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

#161

Post by morkalork »

jtriangle wrote: post #159
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)

Yeah, if you're looking to save the birds, the first order of business is to ban cats, because turns out those cute little guys are rather adept at bird murder.

Apparently that isn't true and just shifting the blame away from the pesticide and agricultural industry which have decimated insect populations. Which are the food source for many birds. Much like blaming consumer's personal choices for CO2 emissions.

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

#162

Post by ars »

User23 wrote: post #141

The Earth’s angular momentum is the exact opposite of renewable. It’s even less renewable than so-called fossil fuels.

True, but it's being wasted anyway. The amount of power dissipated in the daily tides is around 3.75 terawatt, around 3 million times as much.

And don't assume this 1.2 MW adds to that total, a good portion of it is simply substituted.

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

#164

Post by pappn »

debok wrote: post #55
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 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…

I think 100 households per MW in milder climates is very conservative.

Anectdata: I have a ~150 square meter, 50 year old house heated by electricity and heat pump. I live I Norway, and where I live winter temperatures usually don't get lower than -12C. I have 2 EVs that are driven around 50k km a year combined, charged at home every night, simultaneously.

I peak out below 15kW (1h average). That number is deliberate since I get a higher tariff if I go above 15kW. I have some minor smart house installations that most significantly cuts power to my hot water heater if I get close to 15kW, but even without that I would rarely get above 15kW, and never above 20kW.

Average power this January was 4.75kW, December was 4.96kW, August was 2.25kW.

(Edited for typo)

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

#165

Post by bjourne »

morkalork wrote: post #161
jtriangle wrote: post #159

Earlier quoted context omitted.

Yeah, if you're looking to save the birds, the first order of business is to ban cats, because turns out those cute little guys are rather adept at bird murder.

Apparently that isn't true and just shifting the blame away from the pesticide and agricultural industry which have decimated insect populations. Which are the food source for many birds. Much like blaming consumer's personal choices for CO2 emissions.

"We estimate that free-ranging domestic cats kill 1.3–4.0 billion birds and 6.3–22.3 billion mammals annually. Un-owned cats, as opposed to owned pets, cause the majority of this mortality. Our findings suggest that free-ranging cats cause substantially greater wildlife mortality than previously thought and are likely the single greatest source of anthropogenic mortality for US birds and mammals." https://www.nature.com/articles/ncomms2380

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

#166

Post by bronson »

morkalork wrote: post #161
jtriangle wrote: post #159

Earlier quoted context omitted.

Yeah, if you're looking to save the birds, the first order of business is to ban cats, because turns out those cute little guys are rather adept at bird murder.

Apparently that isn't true and just shifting the blame away from the pesticide and agricultural industry which have decimated insect populations. Which are the food source for many birds. Much like blaming consumer's personal choices for CO2 emissions.

What isn't true? https://www.sciencenews.org/article/cats-kill-more-one-billi...

Yes, pesticides are also an issue.

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

#167

Post by mndgs »

methyl wrote: post #67
jtc331 wrote: post #64

Earlier quoted context omitted.

If the average home was using 10kW constant it be using 240 kWh a day, which is enormously high. In terms of average usage an average sized home in the US is much closer to 50kWh a day, so roughly 2kW average demand. That would mean 1 MW is enough for 500 homes on average. The one thing that doesn’t is peak demand load, say when everyone gets home from work and turns everything on at the same time or a particularly c…

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

8.2 kwh/day for a household in Lithuania, neighbours Poland. Sounds about right.

2022 stats: 3.289 TWh during 2022 consumed, 1.1M households, do the math...

Source: https://www.lrt.lt/naujienos/verslas/4/1887046/litgrid-60-pr...

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

#168

Post by moffkalast »

hnthrowaway0328 wrote: post #143

I'm thinking loudly about three questions: 1. How does the maintenance fee and replacement fee look like, per year? 2. Is it possible to develop a home use version? 3. I assume the tide is going to be consistent, but need to dig deeper into this.

> a home use version

> 28-ton, 1.2-megawatt tidal kite

Yes, one for your shower drain.

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

#169

Post by Detrytus »

wongarsu wrote: post #100
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!

Air conditioning makes up a big part of that, made worse by worse insulation and larger houses. Of course Poland needs heating, but that doesn't show up in Electricity usage as most people heat with natural gas or oil.

Actually, most people would heat with coal. Natural gas and oil are far less popular.

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

#170

Post by vitiral »

ksec wrote: post #76
jokoon wrote: post #54

Earlier quoted context omitted.

> Surely there has to be a catch somewhere. Right? Underwater things are expensive to maintain, nothing is 100% waterproof, so rust rust rust. Underwater cables are no joke either, especially if you're building a network of sea cables. Making watertight is not cheap. And there is the question of doing high power electricity under seawater. I'm not an engineer in that field, that I think it is going to being a whole l…

Underwater cables has been done as in all the Network connection across continents. The same with high power electricity under seawater. None of these are new. However they are all 1 to 1 build up. These new tidal kite requires many to one. And I am not quite sure how this could be done. At least cheaply.

> Underwater cables has been done as in all the Network connection across continents.

Those are stationary cables. I don't know anything about this field, but I guarantee you that there are going to be differences.

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