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Comment: Re:fuel weight (Score 2) 81

by rufty_tufty (#48617821) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship

There is no extra fuel as such.
All rockets have more fuel in them than needed for their base mission to account for failure modes. For example if the engines produce less thrust than planned for, it means they can simply burn for longer to still deliver the payload. The Falcon re-usable rockets will use this extra fuel for the flyback if things don't go wrong.
In the event of an engine out on a Falcon 9 it is highly likely that this margin fuel will be used and therefore that Falcon will not be re-usable because it won't be able to fly back.
So yes there's extra fuel, but it's extra fuel that sometimes will be needed for the main mission.

Comment: Re:Ok but that's electricity, not energy (Score 1) 488

by rufty_tufty (#48403105) Attached to: Denmark Faces a Tricky Transition To 100 Percent Renewable Energy

http://en.wikipedia.org/wiki/S...
So it's applicability is that your house will radiate heat to the outside proportional to the 4th power of its temperature. Likewise it will receive energy from the outside relative to the 4th power of it;s temperature, therefore the temperature difference REALLY matters.

Comment: Re:Real-time market approach (Score 1) 488

by rufty_tufty (#48380249) Attached to: Denmark Faces a Tricky Transition To 100 Percent Renewable Energy

Depends, the small things like Lighting (which will all be LED anyway so negligible,) computers and TVs use so little in the big scheme of things they'd be fine to leave unregulated. It's the big things like heating and AC you want to watch out for:
If your house (of the future) is heated by heat pump running during the day warming a heat store that turns on and off as electric is cheap then yes, that will happen for you.
Your fridge will during peak demand times not cool itself(unless it's close to a panic limit), and during really cheap times will slightly over-cool itself.
Your electric car will regulate its charging to try and run only in off peak times (unless you have told it that it needs to go on an exceptionally long run tomorrow)

Industrial usage could be a bigger problem though, but perhaps that ends up running off the semi-predictable wind. Maybe you'd end up in a situation where during winter you couldn't run a night shift at the steel production plant because the solar plants weren't giving out enough power. Maybe this would translate into more expensive consumer products, or maybe it wouldn't be that big of a thing because the times when you have minimal wind AND depleted hydro storage AND No solar AND high demand would be both predictable and comparatively rare.

Yes we'll lose some convenience of life and some things will get more expensive. Maybe you couldn't have those heat stores to aid efficiency in apartment buildings and so they get more expensive to live in reversing the centuries old drive towards the city. Maybe as a civilisation it means we're slightly less efficient, or maybe that's just what we're going to do with all these people who are out of work due to continued automation.
But it's not the end of civilisation unlike some predictions of what will happen with out of control global warming would imply. A lot of things might get n% more expensive, but that just implies that there is more work to do and that might be good for economic activity.

Who knows, but one thing's for certain, fossil fuel reserves are only getting smaller . Sooner or later we'll have to tackle this so we might as well start now.

Comment: Re:Ok but that's electricity, not energy (Score 1) 488

by rufty_tufty (#48379785) Attached to: Denmark Faces a Tricky Transition To 100 Percent Renewable Energy

You might find this interesting:
http://www.newformenergy.com/#...
Shame you can't retrofit them!
Basically PVT solar panels generate (sometimes low grade) heat all year around. Use this with a heat pump. Then use the earth as a massive heat store to provide year round storage. Compared to Ground source heat pumps in which the coolant loop can go subzero during winter months this tops up the heat stored in the ground every day. Even if it just brings it back up to a few degrees C it's better than sub zero and means your heat pump and solar panels operate more efficiently.

Comment: Re:Basic Income (Score 2) 888

by rufty_tufty (#46247379) Attached to: Star Trek Economics

I agree the Star Trek way will never exist but please consider this; roughly the basic human needs are:
* Food/water/air
* Housing
* Clothing - actually not that essential, let's all go naked!
* Medicine - difficult, one for a later post
* Broadband Internet

Let me assert that we can currently produce enough food to meet the calorie intake of everyone alive. Let me also assert there is enough housing for everyone. There already is enough of everything, we just need to maintain it. Well actually there is never enough internet bandwidth but...
That aside, as long as we are prepared to do the work to maintain our current housing and as long as we don't grow the population we're almost post scarcity now. We just need to keep having the food, heating, (medicine) and then the rest is luxuries.
For food, I believe something like 10% of the population is involved in farming and this is a downward trend.
Heating/Lighting - yeah we need some advances in technology to get this one sorted but again I can't imagine there is more than 10% of society involved in energy production. That said for 1/2 my yearly take home pay I could buy a solar panel array that would produce more energy than I consumed. So if I put 1/2 a year's work into it I would have enough power to tide me through the rest of my life (discounting maintenance)

So we have massive gaps in things like transport and mobile phones etc. But we're not far off 100% robotised car plants and tech factories. It's certainly plausible that we could see it in our lifetime.I ask you what else is left in what humans need?

Well there's the service industry, there's design engineers, management, teachers etc; but, really once the basic needs above are met these are luxuries.
To briefly cover medicine, then there is plenty of historical precedent for people who do this voluntarily. Simple put, you could imagine a society where the drugs are mass produced in a factory and people in the community care for each other.

Let's suppose all this happened and maybe 15% of the society would need to work in farming, house maintenance, etc Who would do that?
ME! Somewhat naively I already grow a lot of my own food and keep chickens. From the farming friends I have, yes it is hard work but also very rewarding and were I not an engineer I could easily see myself doing it. Then maintenance wise I love DIY so I would still do that. So really I would love to be one of those 15%, so would almost all of my friends and family.
But what about everyone else what would they do? Perhaps many would sit around and do nothing, many would probably produce art, or maybe there's be engineers free to work on that new massively parallel architecture they have in mind. I honestly believe the service industry would suffer, so good luck getting your starbucks or McDonalds but if that is the price to pay for a liberated society I'll make my own coffee.

So yes I believe we're a long way off the society I imagine, but I don't think it's impossible and with the right willpower I believe we could reach within a few percent of it in our lifetimes if everyone wanted to.
But then any plan that starts with "if only everyone..." is bound to fail.

Comment: Re:Basic Economics (Score 1) 888

by rufty_tufty (#46246867) Attached to: Star Trek Economics

I think when everyone has food, shelter, clothing, education, health and the chance to have at least 2 children, I think we can say that poverty is solved. (I'm not sure as a society we have the ability to quite do that yet for everyone, but it feels like we're close.) It feels like you're arguing that we'll never solve poverty out of some definition of the bottom n% of society is defined to be in poverty because they can't have everything they could desire.
Instead of Star Trek I wish the article would have at least considered arguably the most famous post scarcity society, the Culture. They cover the problem you mention by a mixture of social conditioning - it's considered an illness to want those things, so people are inclined not to go too far overboard out of social convention - and that you can have those things in VR anyway. The Minds there are explicitly stated as spending most of their conscience in virtual worlds. For the odd sentient who would like to become a warlord they've found that virtual worlds are way more entertaining.

For me I see what you mean that most people will always try to be the top dog in their social circle. At the moment in our society that is achieved by possessions and social status. It's easy to picture that in another society that accrual of something else - fame, interesting artworks, new inventions, people helped etc would be the yard stick by which people were measured.
Let me put it this way a man from prehistory who lived in a dessert might view scarcity of water as we view money, something to be acrewed, hoarded and lauded over. That doesn't mean he'd drown, or drink himself to death as soon as you gave him running water from a tap; he'd pretty soon settle down and find something else to define his place in society by.

Comment: Re:Bad Answer to the Problem (Score 2, Interesting) 372

by rufty_tufty (#45214533) Attached to: Wikipedia's Participation Problem

Think how annoying this must be for the established editors though:
You've just got this article prefect and some mayfly comes along and *changes it*. You'd got it the prefect mix of concise and thorough and someone with a different opinion, sorry someone who is wrong comes along and ruins it; and somehow you're the bad boy for trying to maintain standards!
They must be leaving out of frustration too,

(Yes I stopped editing pages or even participating in the talk pages several years ago, they don't want your help, they don't want your input they just want you to read their minds and do their work for them in exactly the way they would do it but any variance from that ideal is removed).

Comment: Re:Meh (Score 1) 123

by rufty_tufty (#45143555) Attached to: Finland's Algorithm-Driven Public Bus

Since we're doing comparative bus fairs here
Cambridge, UK. Where I live has no busses so Bus from the next village (30 minute walk) to the city centre is £4.80 for a day ticket(so about $7.7). About 6 miles each way on the bus.
If I want the bus to work then I've got to go two villages over (lift from the wife) at which point it is £5.80 (about $9), That's about a 5 mile bus trip.

Comment: Re:Why Didn't I think of that? (Score 1) 232

by rufty_tufty (#45141043) Attached to: ITER Fusion Reactor On Track To Generating Power By 2028

People always say that Fusion has always been 20 years away.
I believe it is much more accurate to say that Fusion has always been $20 Billion away. If Fission and Space travel had had the same funding history as Fusion then they too would also probably also still be perpetually 20 years away.
On the bright side ITER looks like it is going to break that impasse!

Comment: Re:Summary says it all (Score 2) 634

by rufty_tufty (#45130925) Attached to: China's State Press Calls For 'Building a De-Americanized World'

No it isn't.

Much of the middle ages were defined by the following process:
* Stable economy and chance brings a few years of agricultural plenty which means more surviving children.
* Population expands to fill the available food and chance brings a year of less than agricultural plenty.
* What do you do if you have a hungry population and lots of them? Easy! Declare war and seize some resources/kill off your excess population - two problems solved at once.

In more recent - and directly applicable - look at Napoleonic Europe, or the Austro-Hungarian Empire or Germany in the '30s.

Let's not forget America is vastly under-populated for a developed nation and one of the larger ones too, so it will have a lot more inertia behind it with these things.

The US has already been doing that for a while

I was trying to make this point, perhaps not as directly but yes the fall of Rome would also be a good analogy. However that in a large part was dictated by there being no-one else who could take over the role, there are several who could and would step up to take over the US's role here, so perhaps the fall of the British Empire would be more appropriate,

Comment: Re:Summary says it all (Score 1) 634

by rufty_tufty (#45130263) Attached to: China's State Press Calls For 'Building a De-Americanized World'

One of the traditional ways out of these sorts of problems is to build up your military and go conquering.
Unfortunately that isn't going to work in this situation given the military is already the biggest both in actual size and proportionate size and there is no-one left to conquer who wouldn't do the economy more harm with the retaliation.

Comment: Re:That's a Lot of Area to go pure solar! (Score 1) 377

by rufty_tufty (#45122645) Attached to: Largest US Power Storing Solar Array Goes Live

A bunch of desert, and $3,000,000,000,000+

So that's your number for all electricity for every house in the US? If you're happy with that number I am. For that much money you would effectively have free energy for the entire nation.
So that's about $10K per person for free energy for life.
Sign me up! Hell I'll take 2!

The numbers seem about right that this plant costs about $20K per supplied house. Assume this is 5-10% of current prices then why aren't we doing exactly what you suggest?
This is speaking as an Englishman but I spend about $1800 per year on heating and electric for my house. $20K to never have a fuel bill again is a bargain. That's the price of a new Kitchen, what isn't there to love?

Comment: Re:Why has this not already been done? (Score 1) 40

by rufty_tufty (#45059551) Attached to: Government To Build 4G Into UK Rural Broadband Plans

most people would wonder what's the hold-up?

As one of those who is suffering at the end of a 4Mbit piece of wet string that passes for a BT broadband connection I have to agree with you.
I wouldn't mind if I really was in a rural area, but this is Cambridge! Well I am rural if you could 30 minutes cycle/12 minutes drive to the city centre to be rural! This is supposed to be one of the high tech hubs of Britain and yet the exchanges haven't been upgraded in a decade and there are no plans to upgrade our local ones either. (The irony is that the latest ADSL chipsets are designed just over the road from me by the company i work for but that's another story).

The reason for the holdup is as far as I can tell why would they bother? The money to be made is in the big cities and because we're classed as none rural we don't get the benefits of the programs mentioned in TFA, however we also have BT saying that it's not worth doing FTTC because there aren't enough subscribers in our village either.
As far as I understand the costs would be because the problem would snowball - well it's only a couple of miles of fibre needed from our cabinet to the local exchange. Except then that exchange would need its links upgrading which would mean about 5 miles more fibre, but then the Cambridge to London link would then need upgrading...

How are they going to re-coup all that investment from me? Well I pay about £30 a month for my broadband. Assume this upgrade would last for a decade before it too was out of date then they've got a mere £3000-ish per user to pay for this upgrade. Assuming say £200 in equipment costs per user port and about £1million per mile of fibre then they're barely making 50% profit!
You can't be expected to run a modern company on those numbers... (as opposed to doing nothing like they currently are and still making the money)

Never tell people how to do things. Tell them WHAT to do and they will surprise you with their ingenuity. -- Gen. George S. Patton, Jr.

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