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Archive for the ‘Global’ Category

Rand Simberg talks about impedance matching. So I’d like to make a post of my comment there (I’ve always wondered why this obvious alternative gets mentioned so little…)

What to do when you arrive at Mars or Earth with your solar electric propelled vessel?

So, the problem with most low fuel demand velocity change schemes is that they only give slow accelerations. Low fuel high velocity change means solar or nuclear electric propulsion and aerocapture mainly.

High delta vee aerobraking is hard to do in one pass – it gets dangerous because of atmospheric variability and potentially other reasons.

Simple: detach a small capsule with the humans that goes directly to the surface (with only days of life support) and leave the untended craft to do multi-pass aerobraking. Hitting van Allen belts a few more times or taking a long time doesn’t matter that much with no humans onboard.

You could also potentially ultimately leave the long distance craft at some Lagrange point instead of LEO. (Cue some clever and complex maneuvers to save fuel – maneuvers that take long.)

Something similar could also be done when a long distance stack is assembled in LEO: send the humans there only after it’s through the belts. They can go with a smallish capsule again. Potentially at some Lagrange point, or in space without any fixed reference, just along the way. It could be dangerous though if the capsule doesn’t have much life support.

Many of these things have potential delta vee penalties as well as timing inflexibilities, but they could have enough other benefits that they should be considered.

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It doesn’t have the same sound as “The Last V-8” now does it? When you look at what’s happening in the world of automobiles, you get some idea of a change. It is always slow, yet I predict that when it happens, probably starting before the end of this year, people are taken by surprise.

Why Would Anyone Buy A Hybrid Car?

It doesn’t have that much better fuel economy than a modern petrol or diesel engine if you drive out of the city, and it costs some more and is complicated. New turbocharged and variable valve engines can do pretty well because they can be built to opearate in a flexible manner. BMW has even introduced a technique that could be called a “virtual hybrid” – where the aircon compressor and battery charger are disconnected when the gas pedal is pushed to the bottom, resulting in extra power available for traction – allowing a smaller engine to achieve the same acceleration.

In some cases, like buses that need to stop often, hybrids make great sense, but otherwise I see the improvements in ordinary direct internal combustion engine driven cars narrowing the gap quite considerably. On the highway the hybrid has no advantage.

A Seemingly Small Addition

Volvo V70 Plugin Hybrid Prototype

So, add a grid recharge capability and you have a plugin hybrid. By itself that’s not much yet though, you have to enlarge the batteries too. Since most trips for most people are commuting and errands, they’re short and can be done entirely on battery power. You also still haul the gasoline engine along and it is used on longer trips. Most problems solved right here? Sounds easy.

Chevy Volt / Opel Ampera is coming soon. And just take a look at the huge number of plugin hybrids being developed, listed at Plugin America. Most of these will be dead ends, but some might make it big.

Pure Electric Cars – The Charging Problem

The problem is, gasoline is very very energy intensive. If a car uses 8 L for 100 km and a 10 kWh worth of energy, then tankage of 40 liters gives about 50 kWh of energy. Done in 50 seconds this stream of gasoline through the hose is worth 1 kWh per second or 3.6 megawatts. High enough temperature superconductors have not yet been invented that would make a hand-attachable 3.6 megawatt car charger possible. If we generously assume 240 Volts and 40 Amperes, the charging power is only 10 kilowatts. The largest home appliances like sauna stoves and water heaters are in the single kilowatts range. They often use 380 V three phase power here, but that gets slightly impractical for a car charger. This thousandfold disparity in energy replenishment speed is striking. An optimistic 10 kW charger would charge a 100 km drive’s worth of energy in an hour. Certainly useful for commuters. Charging as range extension seems doubtful. Our summer cottage is 300 km from Helsinki. If a full battery only lasts the first 200 km, one would have to stop at a loading station for one hour before one could drive the rest of the way. Not realistic. The penalty of lugging around the heavy and complicated IC engine has to be bitten at this point of battery development.

Battery Improvements?

There exist some pretty high energy per mass battery technologies right now, but they are expensive and use rare materials like cobalt that they can never really be mainstream solutions on something that stores energy in the megawatt hour class. Hopefully with enough money now available, some cheaper and less material intensive ways to store electrical energy can be developed.

Your Local Correspondent

Naturally, Finland would be a pretty ideal place to have electric and plugin hybrid vehicles. A significant portion of the populace keeps their cars parked in a spot with an electric socket nearby – those house timers that turn on the cylinder block heater on an hour or so before leaving for work in the wintertime, meaning less fuel use and wear for the engine. It is trivial to use those 240 V outlets for electric car charging. Also, electric cars are actually manufactured in the city of Uusikaupunki, Finland by Valmet. The Th!nk City is one. Too bad because of insane tax policies, it is not actually sold here – at the moment you can only get them in Norway, Austria and Holland. The Fisker Karma electric sports car will also be manufactured in “Uki”. I think they have a long nose on the car for Freudian reasons – since it doesn’t need to hold a long block internal combustion engine – or maybe it’s just that buyers are conservative. And then there’s the e-cars now project aiming to refit old Toyota Corollas with electric motors and batteries. But there’s more.

Automotive X-Prize

There’s that going on, which is actually interesting! My favorite vehicle is the Peraves E-Tracer.

Here are the results from August 2 but I still don’t know what will change / what is coming because the pages are unclear: [EDIT: fresh info at the blog indicates some testing is still going on]

1st Place Team Lithium Ion Motors of North Carolina (125 MPGe average fuel economy for the event)
2nd Place RaceAbout Association of Finland (0.179 seconds behind the leader and 100 MPGe average fuel economy for the event)
3rd Place TW4XP of Germany (11 minutes, 36.9 seconds behind the leader and 139 MPGe average fuel economy for the event)
4th Place ZAP of California (DNF – 48 laps completed)
5th Place Aptera of California (DNF – 18 laps completed)

The Raceabout team is from Helsinki’s Metropolia university of applied sciences. They have a long background of building electric vehicles, and it’s nice to see something in the competition that looks like an actual car, yet still manages to do so well.

RaceAbout's E-RA vehicle in the Automotive X-Prize 2010 competition

Hopefully the politicians here can get something sensible done, and the super-high taxes on electric vehicles (basically, anything that isn’t gasoline or diesel is considered fishy and is taxed hugely) can be dropped so we can start seeing more of them here! The current situation is a travesty!

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Too much to fit into one update. The leads could be

Communisms’ legacy

  • in the Baltic states
  • in East Berlin
  • in demographies
  • its relation to other genocides like the holocaust
  • a prison
  • how do the people live today
  • Ignalina and its replacement
  • (Peripherally a subject matter, the western powers’ somewhat interesting views on Finnish-Soviet wars and relations and their potential wagings of war against the reds – project Pike forum summary and the book here)

Russian forest fires

  • Beriev’s share price (A Be-200 appears on the video 15 seconds in, hat tip to Secret Projects)
  • organization of society and its ability to handle crises
  • the smoke in Helsinki because of that
  • should they care

Hot weather

  • Here, after the coldest ever winter comes the hottest ever summer
  • Is it largely just winds from the southeast’s continental hotness – when usually they blow from the more marine southwest?

Climategate blahblah

  • BBC has apologized and some NYT reporter has said the NYT should apologize on some small back page article.
  • Follow Michael Tobis for climate related news

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I just updated the blog title and again just watched the page and the blurb.

It’s when we start working together that the real healing takes place, … It’s when we start spilling our sweat, and not our blood.

It’s a quote of David Hume, my favorite philosopher. I haven’t read his books though. I was reading a Finnish translation of one but it seemed so tedious with the language that I couldn’t bother. So me favouring him is based on the works of others about him.

The quote reminded me of the conflicts that I’m witnessing. The subject line matter needs to be done. At the moment many parts of climate software seem to be science software – written by people in a hurry with little planning, and code that has seen different people adding bits and pieces here and there, making it a big mess. Fortran and supercomputers and all that. Well, most software is a mess. Twenty man years, said MT. That’s a small amount of money considering how much is at stake and even compared to the amount of huffing and puffing efforts around the subject. I am available.

What else needs healing and sweat spilling? Well, quite many things. Including stuff in my personal life.

There are lots of old (sometimes Fortran) code packages hanging around. Nuclear stuff, rocket trajectory calculations, rocket engine chemical/thermodynamics performance… You name it, anything a young man is interested in seems to depend on these archaic pieces of software. So there’s a lot of potential work here but it seems so big for just a lone person to do much on their own free time.

The blog title picture is just some hinge flapped NACA foils simulated with the vortex lattice method in QFLR5. That actually IS a free software project, mostly by Andre Deperrois and uses Mark Drela’s XFOIL for 2D calcs. In the picture, the front wing has NACA 4415 with 6 m span, 1 m chord, 25% chord 15 degree full span flap, and the tail is a NACA 0012 with 2 m span 0.5 m chord, 40% flap or elevator at -15 degrees. Flying at 5 degrees AoA (plus 4 deg to the front wing) and 18.9 m/s, lifting about 2000 N. Absolutely no guarantees about the results.

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Nuclear plants operate at only a few hundred degrees Celsius, so they don’t have very high thermal efficiencies. Thus only a small part of the nuclear energy is changed into electricity and most is lost with the coolant fluid, about two thirds. Could it be used for something?

Traditional coal plants have long given their waste heat for district heating (and some cooling in the summer too!). This “free” energy is distributed as hot high pressure water in large pipes. It works great, especially in dense areas. This reduces coal usage quite a bit if you compare it to heating with coal electricity, or oil usage if you compare it with heating with heating oil.

In Russia special nuclear power plants, especially for isolated cities included provisions for large amounts of district heating. Though this means that the plant needs to be quite close to the city for it to be effective. It’s not done in the west. Could it work in Finland?

The power company Fortum is probably building a third unit to the Loviisa power plant complex some 100 km east of Helsinki, and it’s proposing to Helsinki that the new unit could provide a gigawatt of cheap district heating for the city. But Helsinki at the moment owns its own power generation company, Helsingin Energia (Helen), and is sceptical of the idea. Helen’s coal plants provide the current district heating and there are rules about the maximum size of a plant in the grid – if over 40% of the district heat would be provided by one plant, when it went down for some reason., there could be a catastrophe.

A 100 km long very large hot water tube system might also be very expensive. There exists a roughly 100 km long  fresh water tunnel carved in rock, providing water to Helsinki from lake Päijänne, so there is some expertise regarding such large scale subterranean building.

Another way of thinking about nuclear heating is to generate normal electricity but use it to power a heat pump at the heating location. This can increase the heating power as much as five fold – ie 5 kW of heating for 1 kW of electricity. This requires no district heating pipe infrastructure but the heat pumps are expensive. They are becoming more common in less dense living areas though and are a good way to reduce electricity use if they replace direct electric heating. They also increase peaks since the five multiplier can drop to two when it gets much colder outside – because the temperature difference that the pump works against is larger.

Political ties

Helen is a very good business for the city and its profits lower the local tax rate quite a lot. Those fools in the neighbouring city of Espoo sold their own power company abroad, started playing in the stock market with the money and have lost quite a bit. (And that was before the recession!)

Helen is also a stakeholder in the Olkiluoto 3 nuclear plant that is being built in Eura, in Western Finland, they’ll use part of the electricity that will be generated there. The consortium leader, Teollisuuden Voima, is a competitor to Fortum.

There seems to be no love lost between Helen and Fortum.

History

Nuclear power plants have been proposed for city part heating, one was even in operation in Sweden. It was built securely inside rock, but it was shut down after a mishap. There were plans to put such a small nuclear plant in the Malmi northern suburb of Helsinki in the sixties or so, but that plan was cancelled. Also, in the past, the large Granö island in front of Helsinki’s east side neighbour Sipoo was charted for a nuclear power plant, but it was cancelled and in the end only Loviisa and Olkiluoto were built. Now that the western part of Sipoo has been grabbed by Helsinki, some have proposed to dust off the old plans and put a reactor on the island. 🙂 At one point when no plants had been built yet in the country, Inkoo, some 50 km west of Helsinki was also one of the possible plant locations. The pipes from there would have been easier. There already exist quite large power grid connections in Inkoo because an emergency coal plant is located there. It could be one compromise site for a small nuclear plant – far enough but not too far.

Sources: personal communications with various people, an article in Tekniikka and Talous (in Finnish) and Finnish Wikipedia on Finnish nuclear history and air heat pumps.

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Assume a glacier that provides summer water for a billion people. What is its value, if it is destroyed by global warming? Since it currently provides services for free, it could be calculated as zero, according to some. Hence, a hypothetical economic activity by those people that gave them one dollar in total while destroying the glacier completely, would be worth doing? That’s suicide economics.

The word VALUE, it is to be observed, has two different meanings, and sometimes expresses the utility of some particular object, and sometimes the power of purchasing other goods which the possession of that object conveys. The one may be called “value in use”; the other, “value in exchange.” The things which have the greatest value in use have frequently little or no value in exchange; and on the contrary, those which have the greatest value in exchange have frequently little or no value in use. Nothing is more useful than water: but it will purchase scarce any thing; scarce any thing can be had in exchange for it. A diamond, on the contrary, has scarce any value in use; but a very great quantity of other goods may frequently be had in exchange for it.

Who’s the radical greenie who wrote the above? Mark Sagoff wrote an essay on stupid valuation of nature’s services back somewhen, where he made the above quote. Find out there, who said it…

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A quick way to get up to speed on Thorium and LFTR, aimed at lay people.

I seriously doubt their cost and schedule stuff. One needs to do material science tests with this, so it’s going to take longer.

But otherwise. It is the industrial solution for the world. It is perhaps not the best electricity solution for everyone, only perhaps 90% of the population, weighed by current CO2 production.

Swap your yearly tonnes of carbon to grams of Thorium.

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