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Comment: Re:Niche energy (Score 1) 71

by Rei (#48471461) Attached to: WaveNET – the Floating, Flexible Wave Energy Generator

A lot of companies are involved in a lot of renewables tech research. That doesn't mean that any particular one is going to be profitable. The vast majority are going to be big failures.

Wave power's track record so far has been subpar to say the least. And looking at their diagrams, I can't imagine that they're not headed straight for the same fate. Even if we assume that their numbers aren't overly optimistic, their design looks like it would involve several times more steel per nameplate capacity than a wind turbine tower. And they're operating in a much harsher environment. No rotors, but they're dealing with major hydraulic pumping instead. It just doesn't look like a winner to me.

If it was my job to have a go at wave power, I can't imagine going for anything involving large amounts of structural steel or hydraulic pumping; I'd keep it simple and just go for a grid of cables (potentially a high tensile strength UV-resistant plastic), anchored at the edges to keep tension up across the whole grid, with the only slack available involving the grid pulling on regularly spaced springloaded reels (the rotation thereof generating electricity), with any combination of floats, drag chutes and weighs/anchors to cause the needed tug from the movement of water. No pumps, no hydraulic fluid, no large compressive-loaded structures, just a tensile structure that would be (proportionally) lightweight and easy to deploy.

But hey, it's not my industry ;)

Comment: Re:It boils down to energy storage costs (Score 1) 617

by Rei (#48466617) Attached to: Two Google Engineers Say Renewables Can't Cure Climate Change

And from their numbers, it doesn't look like they're using a reasonable estimate for Chernobyl. There've been some ridiculous estimates out there from both sides, ranging from "only the couple dozen who died directly" to "millions".

One can look at the approximately 10% higher mortality rate within the exclusion zone to get a rough sense of the consequences, but without knowing demographics, it's hard to draw conclusions from that. Probably the best (peer-reviewed) analysis I've seen compared doses with the US military's mortality data from exposure to the nuclear bombings in Japan. You get a figure of about 4000 extra deaths with moderate confidence and 5000 with low confidence (the error bars can be in either direction). So very rough ballpark of 9k deaths, plus the first responders and the like.

Yes, even when you include things like that, nuclear's death toll is lower than coal, no question. But it's not as low as they make it out to be. Their bias is obvious.

The deadliest nuclear accident, Chernobyl, was caused by defense department testing.

Yep, nuclear disasters can happen from both man and nature. That's hardly a comfort. Will "defense department testing" cause the next major nuclear accident? Very unlikely. But there almost certainly will be a "next major nuclear accident" - we just don't know what form it will take. It's a "known unknown".

Whereas Fukushima was all user error?

No. But if you're going to include "dam-induced casualties from storms", then you should include "people spared from storms by dams" also, it's only fair. And thus hydro's death count would be strongly negative.

Perhaps it is possible to offset renewables in such a way that they can provide 90% of our power needs, but no one has ever done it.

Speak for yourself. I live in Iceland where over 99,9% of the grid is renewable (primarily hydro). 99,9% renewable baseload at that. There's even serious preliminary work looking into building the world's longest submarine power cable to export power to the UK.

Again, not saying that hydro is my preference - I've stated my preference above. Just pointing out that your claim is wrong.

(Concerning the power cable: I'd support if A) they'd only be adding geo plants and wind to meet the extra power need, and B) the government would tax the power sales to the point where the cable makes just barely enough profit to economically justify its existence... but I'm sure that A) they'd probably just dam up the highlands some more - who gives a rat's arse that we have some of the world's most abundant and cheap geo and wind power that could easily compete on the European market, hydro gives a tiny bit more profit margin!; and B) the government would hardly push back at all on power export royalties because, hey, JOBS! Jobs damming up the highlands!)

Comment: Re:Next step - Semiconductors (Score 4, Funny) 68

by Rei (#48466211) Attached to: ISS's 3-D Printer Creates Its First Object In Space

Close, but your syllable count is a bit off. Something like this would work:

fuck ink jet printers
fuck all those fucking printers
i fucking hate them

Technically, though, you're supposed to have a connection with nature for it to be proper haiku. So maybe something more like

ink jet printer rests
at the bottom of the bog
piece of shit printer

Comment: Re:Next step - Semiconductors (Score 4, Interesting) 68

by Rei (#48466155) Attached to: ISS's 3-D Printer Creates Its First Object In Space

They did. But first off, to correct the GP: Concrete does not release CO2. It absorbs CO2 (slowly taking back the carbon that was released during the cement's creation). So this messed up their balance equation. Metabolism was supposed to consume O2 and make CO2, while photosynthesis was supposed to consume CO2 and make O2. But with the concrete locking up the CO2, the output of metabolism was being locked up and not being converted back to O2, so the O2 levels declined.

It's a simple oversight, but one that we're very lucky was made on Earth and not on, say, Mars. More foresight could have caught it, but there's always something that slips through the cracks. A number of other issues showed themselves, such as unexpected condensation adding rain to areas supposed to be rainless, less light than anticipated making it into the habitat, certain inspect species proving incompatible with the environment while others proving to be pests, so and so forth. They also had big problems with wild fluctuations in CO2 by time of day and season - they didn't have a massive amount of atmosphere to buffer it, so levels collapsed during the day and shot up at night. A lot of people complained that the project wasn't focused enough on the science, but I think they learned an awful lot of important things that could prove critical if ever trying to grow crops on another planet.

(The psychological aspects and how the crew split into two bitterly divided factions is also a real cautionary tale)

So anyway: after the first Biosphere 2 experiment was terminated, they sealed the concrete and started another one. But the second experiment was more doomed by politics than anything else. The on-site management was foreceably evicted by federal marshals. Former biosphere members broke into the facility so that the people inside could know what was going on outside (in the process, ruining the sealed environment). And then a couple months later the management company was dissolved. Altogether the second mission lasted less than half a year. It was a total disaster.

Comment: Re:Enemy (Score 5, Interesting) 84

by Rei (#48465661) Attached to: New Snowden Docs Show GCHQ Paid Telcos For Cable Taps

Who's the actual target?

I once knew someone who was in military intelligence during the Cold War who had lots of good stories about where the intelligence to analyze came from. One good source was an undersea Soviet cable that the US had covertly tapped. Another was their predecessor to cell phones. They were analog and unencrypted, but they generally realized the risk and didn't use them anywhere near where there might be a listening post. However in issuing guidelines for their usage they apparently miscalculated on the fact that the signals also propagate up, believing that the low power transmissions would be too weak and distorted by the time they got to orbit to be demodulated. The US however had a satellite that could do precisely that.

The Soviets were also very good at covertly tapping US communications. They (and their Russian successors) also made good use of them in other ways. In the Chechen conflict, their leader Dzhokhar Dudaev stayed in communications with his contacts via short calls by satellite phone. The Russian solution to this was to create a system that would specifically recognize his phone, and mounted it to a HARM - the sort of missile normally used to take out radar transmitters, which homes in on a specific radio signal. It was the world's first - and only - "Anti-Dudaev Missile", and worked quite effectively.

Comment: Re:It boils down to energy storage costs (Score 1) 617

by Rei (#48465523) Attached to: Two Google Engineers Say Renewables Can't Cure Climate Change

It's long been known that the temperature of the thermosphere is highly dependent on what the sun is doing. It doesn't "store" energy, and there's essentially nothing above it to block it from radiating out into space. It also represents a mere 0.002% of the atmosphere.

It's not the thermosphere whose temperature people care about. It's the first few dozen meters of the troposphere that matters.

Comment: Re:It boils down to energy storage costs (Score 1) 617

by Rei (#48465517) Attached to: Two Google Engineers Say Renewables Can't Cure Climate Change

and it's about the coolant effect of CO2 in the middle and lower atmosphere, not the troposphere

You keep using that word. I do not think that it means what you think it means.

(Hint: the troposphere *is* the lower atmosphere - and if you define "middle" by "half of the mass" rather than "half of the altitude", it's that too)

Comment: Re:It boils down to energy storage costs (Score 1) 617

by Rei (#48465473) Attached to: Two Google Engineers Say Renewables Can't Cure Climate Change

Quite true. People complaining about randomness on the grid and uneven supply usually don't stop and consider that the grid already faces huge randomness from the other side - demand - and deals with it just fine. Baseload is indeed a problem, not a solution, and peaking and storage are interchangeable.

I think people focusing on storage are letting "perfect" be the enemy of "good enough". I think storage is the ultimate future, but we're talking long term. Mid-term, peaking is the answer. Switch over the lion's share of generation to renewables, get them as type-diverse and geographically-diverse as possible, use peakers to fill in the gap like we already do, and you've taken out 90% of the problem (at least on the electricity side - still have to deal with transportation and other anthropogenic emissions).

Comment: Re:It boils down to energy storage costs (Score 1) 617

by Rei (#48465465) Attached to: Two Google Engineers Say Renewables Can't Cure Climate Change

That page is ridiculous. They credit 171k deaths to hydro from a single Chinese dam failure without bothering to mention that it failed because of a freaking cat-4 (nearly 5) typhoon. And dams have saved far more people than that through flood control. The 1931 floods in China alone killed as many as 4 million people.

And beyond that, pumped hydro != conventional hydro. Pumped hydro generally uses proportionally small reservoirs, and it's not usually situated in populated areas like river valleys. Where there's a big coastal rise it's popular to use the ocean as the lower reservoir.

As I described earlier, nuclear is a bloody awful choice if you're looking for a peaker (not going to go into why yet again)

Lastly, hydro, even pumped hydro, isn't my preferred solution (for ecological reasons). My preferred mid-range solution is a geographically diverse (stretching across multiple climate zones that don't experience the same weather at the same time) high power HVDC grid with diverse renewables generation in each location (so that their randomness doesn't correspond well with each other), with natural gas as peaking. You could probably get a 90% renewables / 10% gas solution in that manner. And a HVDC grid provides a ton of other benefits beyond just reducing net randomness - it syncs up disjoint AC grids allowing power sharing, it spreads out demand peaks over broader regions where they occur at different times due to different timezones, it makes underwater transmission lines much easier, it lets you use energy resources that are "the best, period" rather than having to settle for "the best that's close enough to the demand", it lets industry position itself more ideally, it helps you keep pollution away from populated areas, and on and on.

Comment: Re:It boils down to energy storage costs (Score 1) 617

by Rei (#48465431) Attached to: Two Google Engineers Say Renewables Can't Cure Climate Change

Holy Red Herrings, Batman! It's almost as if I wrote "If you have HVDC, and and solar power generation in a single geographic region suddenly become stable", rather than what I actually wrote:

Probably the best thing you can do is simply have a powerful HVDC grid so you can move power between different geographic regions and to use different types of renewables techs

Even in Germany, solar plus wind alone is much less random than purely solar or purely wind. But combined over a broad geographic region, the figures are surprisingly stable. HVDC lines also (their main purpose today) link you up with other regions so that you can use them as peaking when you need it and they don't (esp. regions with hydro, since hydro is much more total-energy-limited than power-limited, and nameplate power capacity can be uprated if necessary with little ecological impact and proportionally very small cost).

then your "high voltage DC net" myth will collapse.

Which is why Germany and Denmark are in a constant state of blackout?

Honest policy by a - say - PHD-in-physics politico would be to demand storage for at least 5 days for every Watt of "renewable" power installed.

That argument of yours makes no sense, since it doesn't account for capacity factor or generation profiles.

It would mean lifting up the entire lake constance by dozens of meters.

This claim is unevaluatable without knowing how much backup energy you're meaning to provide.

But if you are just a fucking liar with a physics PHD, you skip the storage.

Storage and peaking generation are 100% interchangeable. You can use any combination of either. And as stated, the need for either storage or peaking generation depends on the randomness of the supply, and 1) the more types of sources you use, and 2) the broader the geographic area you collect from, the less net randomness in the generation.

It should be noted that the power grid today is already highly random - not in terms of supply fluctuations, but demand fluctuations. Nighttime demand averages about a third of daytime generation, and there are sudden spikes and dropoffs at certain times of day. The current approach to the grid - peaking - deals with high levels of randomness just fine.

(it should also be noted that HVDC across time zones also helps you level out time-of-day demand spikes)

Vitamin C deficiency is apauling.

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