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Can the Sun Realistically Power Datacenters?

fgouget Re:Obligatoriness Extraordinaire (237 comments)

The numbers for tilt panels are different than the numbers for fixed panels.

Please re-read. The numbers I gave are for fixed panels (i.e. where the tilt is fixed).

about a week ago
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Can the Sun Realistically Power Datacenters?

fgouget Re:At least the infrastructure is in place (237 comments)

If you're trying to heat the building - not so much. If the panels are in contact with the building - not then either - they tend to capture a lot of heat. If you get them far enough away that outside air removes the heat - then shade may help.

The only datacenter that needs heating is the one that's empty and thus either soon to be full or soon to file for bankruptcy. Also there's always quite a bit of unenclosed space between the panels and the roof, even in cases where the panels are flat rather than at the latitude tilt. So expecting the heat to transmit from the solar panel to the roof seems pretty unrealistic.

about two weeks ago
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Can the Sun Realistically Power Datacenters?

fgouget Re:At least the infrastructure is in place (237 comments)

All else is not equal. If you didn't have solar panels up there, you could put some light-colored paint on the roof, which reflects much of the sunlight. Solar panels tend to be quite dark, and get quite hot since they aren't anywhere near 100% efficient.

They are also not flat against the roof meaning there's a big layer of mobile air between them and the roof. So the heat does not transmit from the solar panel to the roof. Hence all that remains is the shading which does mean they considerably reduce the heat loading on the roof.

about two weeks ago
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Can the Sun Realistically Power Datacenters?

fgouget Re:Obligatoriness Extraordinaire (237 comments)

Average solar insolation is more like 5 sun-hours/day, not 8, in good locations. Much less in places like Germany.

Actually it's 4.8 hours/day for a fixed tilt panel in the worst location of the 48 lower US states (St. Louis, Missouri). So almost any US location is guaranted an average of more than 5 sun-hours/day. Germany is indeed a bit worse but not as much as some think. Still Berlin can only count on about 3 sun-hours/day. That previous link also clearly shows that there's significant seasonal variation. This can be mitigated a bit by using the grid to connect to less affected places. Still a 100% renewable scenario does require the need for either lots of seasonal storage (the hardest kind), or lots of over-capacity.

about two weeks ago
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Can the Sun Realistically Power Datacenters?

fgouget Re:Obligatoriness Extraordinaire (237 comments)

Storing solar power is an issue in niche applications, and it is an issue in a future fantasy world where 100% of our power is solar.

Very true, and not even a real issue in a 100% renewable scenario. The entire state of South Australia ran on 100% renewable power for a full working day for the first time last week. The bulk of that was wind generation, with rooftop solar adding a significant contribution.

So your counter example is a 100% renewable scenario that ran on 100% renewable for less than a day! And the next day that 100% renewable scenario ran on less than 100% renewable??? What this proves is that such a scenario cannot exist without energy storage.!

about two weeks ago
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A 16-Year-Old Builds a Device To Convert Breath Into Speech

fgouget Helmet (67 comments)

So that's how Darth Vader's helmet works...

about a month ago
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Power Grids: The Huge Battery Market You Never Knew Existed

fgouget Re:What's with the Tom Murphy links anyway? (245 comments)

Also why do you keep providing links to some guy that straying so far off practical models that he was describing enough energy storage to power a continent for a week?

He's looking into what it takes to have a 100% renewable power grid. As mentioned in a previous post, providing storage for a day or more could well be needed in such a scenario. And if you read his analysis you'll see that whether you try to provide storage for a week or a mere day does not matter much: pumped hydro does not cut it in either case, by far.

You see to be unable to get past "we have a solution based on cheap natural gas that works now". But assuming natural gas will remain cheap, plentiful(*) and have no nasty environmental side effect is taking quite a risk.
(*)We have proven reserves for 56 years, at 2010 consumption levels, less if consumption increases at it historically does.

about a month and a half ago
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Tesla Plans To Power Its Gigafactory With Renewables Alone

fgouget Re:Musk worship (260 comments)

Yes. It's getting huge tax breaks here. It got a nearly free auto plant from California.

It gets $7500/car in subsidy from the feds. Many states give $1500 to $5000 on top of that. Some countries they sell into give tens of thousands equivalent.

The feds don't give that $7500 subsidy because the brand of the car is 'Tesla'. They give it because it's an electric car. There's over a dozen models from BMW, Fiat, Ford, General Motors, Nissan and others that get the same subsidy. So spinning this subsidy as "the feds are helping Tesla" is a lie. Same thing for the state subsidies.

If they charged $90K for a car which is luxury equivalent to a Hyundai Sonata I would. It's a nice car, but it doesn't measure up to other $90K cars on luxury.

The Tesla Model S is a full-size luxury liftback which ranks second against other "Super Luxury" cars and has a 0-60 acceleration of 4.2 to 5.9 seconds (depending on model). The Hyundai Sonata is nowhere close to being in the same class seeing as it's a mid-size car and not as sporty with a 0-60 acceleration of 6.5 to 8.5 seconds. So again you're ill-informed or disingenuous.

about a month and a half ago
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Power Grids: The Huge Battery Market You Never Knew Existed

fgouget Re:Anders Bylund is not Tom Murphy (245 comments)

Trust in the smart grid to automatically reduce demand by 25% for a full week?

That's making an assumption of solar capacity far beyond the wildest dreams of those that wish to supply it. I'll assume it's a simple error instead of a deliberate attempt to mislead.

Wow! I see neither the solar capacity assumption, the error or the attempt to mislead. I must be so dumb. Or did you mean there's no way PV can ever provide a significant portion of our electricity needs?

Tom Murphy is a physicist, not a journalist

However the person I referred to is not Tom Murphy is it?

Given that it follows the section that started with "So that's dealt with the article that kicked off the discussion - now for the one you've linked", I'd say it is.

Due to the nature of grids and distributed power generation it's the wrong approach anyway since there is no requirement to provide enough storage for a single second. [...] For a start there are so many gas turbines sitting on coal seam gas or similar just waiting for a chance to spin up for more than an hour or two every few days.

This relies on the assumption that fossil fuels will remain cheap and plentiful for decades to come, and that we don't need to reduce their use for environmental reasons. I think both are incorrect. It also assumes that building and operating spare gas turbines to deal with variable load is cheaper than using grid storage. That's correct for now but it's no reason not to look for better solutions. Cheap electricity storage would have other uses besides helping the grid deal with variable load and production. For instance it would help wind turbine and PV plants operators better monetize their production by not forcing them to sell on the spot market.

I thought you Americans got used to such things when you embraced deregulation and let Enron et all in the door?

I'll let Americans speak for themselves.

about 2 months ago
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Power Grids: The Huge Battery Market You Never Knew Existed

fgouget Re:It already is enough because ... (245 comments)

So that's dealt with the article that kicked off the discussion - now for the one you've linked. A key assumption is a point source where the electricity is coming from and not a large distributed grid which is the only sane way to model a very large number of little generators all over the place. So there's no wind - look at a weather chart - of course there's wind, plenty of wind, it's just not where you are standing, and there's more than one windmill in the country. So there's cloud - does it cover Vegas as well?

Sure there's wind, but not necessarily plenty, and half the solar panels in the north of the US may be covered by snow. Which means that for a week you may have electricity production that's 25% below demand. So what do you do? Trust in the smart grid to automatically reduce demand by 25% for a full week? Forcefully reduce demand through brownouts? Or can we simply have two days of electricity storage to make up for it?

Now Tom Murphy's point is not to say that this is impossible, but that it's not trivial as some people (like the GP) seem to think. Hence if storage the route we want to take we have serious work and research ahead of us. Also just building the energy storage infrastructure (e.g. al that concrete for pumped hydro) will itself use up lots of energy, so we should do so while energy is still plentyful. His further point was that it would be much simpler to reduce demand by travelling less, eating less meat, better insulating buildings, heating them less, etc. While there's no doubt stuff to do to reduce demand he is definitely an outlier in how far he is willing to go to do so.

Of course a lot hinges on how much the spread of energy sources can limit the shortfall, and how long such shortfalls can last. My understanding is that neither of those are quite settled issues yet. Also that can be somewhat mitigated by overbuilding renewable production capacity, though if we find a good storage solution that might not be the most efficient use of resources. In any case researching grid storage makes sense to keep our options open, though personally I'm still rooting for the distributed car battery storage.

Stuff like this is, to be frank, is just people out of their depth railing against change and looking for a feeble excuse to keep them afloat, and it's designed to mislead. So I'm sorry to say fgouget and many others, you've been suckered by a journalist that probably knows less about the topic than yourselves.

Tom Murphy is a physicist, not a journalist, and has obviously taken quite an interest on the subject of energy as can be seen from his blog. So he's certainly as knowelegeable as you or me as far as evaluating the rough feasability or cost of various solutions. And while I trust him to do the math right, I don't trust him about evaluating how far society can be changed. As for the Slashdot article, it was essentially content free: there's a thing called grid storage, batteries used for it have different requirements, some people are doing research on that topic. Is that news? Did anyone on Slashdot not know that already? Hard to get sucked in by a journalist that has nothing to say.

about 2 months ago
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Power Grids: The Huge Battery Market You Never Knew Existed

fgouget Re:flywheel (245 comments)

There's a much easier solution, already in operation - pumped hydro power plants.

Pumped hydro works but just cannot be scaled to provide sufficient storage. Hence other solutions are needed. Actually it's likely nothing short of a combination of many approaches will be enough.

about 2 months ago
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Canada Tops List of Most Science-Literate Countries

fgouget Re:Biased (221 comments)

Yep. There's no inherent conflict, and the conflicts that did take place, are usually portrayed in a way that would make historians cry.

For example - Galileo

Wrong counter-example as it's not one I mentioned and it's irrelevant to current events.

about 2 months ago
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Canada Tops List of Most Science-Literate Countries

fgouget Re:Biased (221 comments)

It seems to presuppose the long-discredited Conflict Thesis, which states that religion and science are inherently always in conflict.

Long discredited? That may be so but we still have lots of religious people who oppose teaching evolution or reproductive biology on a religious basis, disbelieve climate change in disproportionate numbers, believe the earth is about 6000 years old, or even, in some parts of the world, think that girls have no need for education.

Finally most religions require one to accept truths on faith, that is without objective reproducible proof. That's the anti-thesis of the scientific method.

about 2 months ago
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Rightscorp's New Plan: Hijack Browsers Until Infingers Pay Up

fgouget Re:"Hard redirect" (376 comments)

I used the phrasing almost all specifically because it may be possible to bypass the controls using UDP.

If the block can be bypassed using UDP then the ISP made a 'big stupid error' as I mentioned. Their router should simply not forward any packet outside the local network until the customer provided his credentials. That covers IPv4 (TCP, UDP, ICMP, others), IPv6, and anything else, whether they support it or not. For ADSL it should be pretty easy to identify the customer's line and redirect anything coming from that line, leaving no possibility of escape. Customers who connect to their ISP through a shared medium, like cable or WiFi, there's an escape route which is to hack their hardware/software stack to impersonate another customer on that shared medium. But that's obviously illegal and furthermore there's no point for them to keep paying for Internet access in the first place.

about 2 months ago
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FarmBot: an Open Source Automated Farming Machine

fgouget Printer? Where? (133 comments)

They plan to take this technology to an entirely new level by creating a 3D Printer that is capable of, you guessed it, farming.

So it's not a printer in any sense of the word. Great start for that article. The rest really goes downhill from there. Shouldn't it have been published on the 1st of April?

about 2 months ago
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Rightscorp's New Plan: Hijack Browsers Until Infingers Pay Up

fgouget Re:"Hard redirect" (376 comments)

Yes, it would work on almost all browsers and there likely would never be a patch that would get around it.

No, unless they made a big stupid error, it would work on every browser past, present and future; as well as every other application trying to use the Internet; and no patch can get around that. That's because you cannot access the Internet if your ISP does not want you to. You could however get a contract from another ISP, assuming Rightscorp did not put you on some sort of industry-wide blacklist.

about 2 months ago
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Microsoft Research Brings Kinect-Style Depth Perception to Ordinary Cameras

fgouget Hyperlapse (31 comments)

They should rename HyperLapse to SmoothLapse, StableLapse or CleanLapse.

about 2 months ago
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The Hidden Cost of Your New Xfinity Router

fgouget Power usage seems unrelated to Xfinity (224 comments)

The blog post did not compare the power usage with the Xfinity hotspot enabled and disabled. So all we can say is that the new Comcast modem is crap and wastes power by the bucket, just like the old one apparently. So while the title and many comments here seem to imply the extra cost is all due to the Xfinity Hotspot functionality, that view is so far not supported in any way.

about 3 months ago
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The Hidden Cost of Your New Xfinity Router

fgouget Re:Service in exchange for a free modem? (224 comments)

The GP post is more an indictment on the mob^w justice system that all too often seems to presume guilt before evidence beyond a reasonable doubt is required.

Sounded more like the rant of a paranoid tinfoil hat wearer. That or given that hotspots are not a newfangled invention he should have no problem finding dozens of small businesses or hotels that got raided because they offered internet access.

about 3 months ago
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Idiot Leaves Driver's Seat In Self-Driving Infiniti, On the Highway

fgouget Re:Huh? (406 comments)

Fully autonomous vehicles are scary for manufacturers because they potentially shift all liability to the manufacturer.

I think a simple solution is to turn the self-driving functionality a subscription-based service. Under that model the self-driving mode would require a network connection at the time you try to enable it and would check that you paid your montly subscription. Then you can use it for that month. The manufacturer would collect the subscriptions and use them to provide insurance in case of an accident. Then it's up to the manufacturer to set the subscriptions high enough or get the accident rate low enough for it to work out, like any insurance service.

Combined with some extra services like battery rental (for electric cars), this could even let car manufacturers shift to a business model close to the rasor+blade one (not saying that would be good for customers though).

about 3 months ago

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