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Is the Tesla Model 3 Actually Going To Cost $50,000?

floobedy Re:Still pretty affordable (377 comments)

I don't think that's right. I've known a couple of EV owners in CA who claim that the electricity costs are less than half what gasoline costs, per mile. The Chevy Volt uses 10 KwH of battery capacity to travel approximately 40 miles. That's 0.25 KwH/mi, which is $0.0375 per mile with electricity at $0.15 per KwH (in CA). Gasoline is about $4 gal and can take a car about 35 miles, which is $0.1142 per mile, which is ~3x as expensive as the EV.

yesterday
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To Really Cut Emissions, We Need Electric Buses, Not Just Electric Cars

floobedy Re:Everything old is new again (486 comments)

I didn't know that. It's strange that SF owns its own power plant for city services.

I suppose I can act like an economist here, and say that electricity for public services in SF still isn't really free. SF could sell that electricity for 6 cents per KwH, so there's forgone income which should count as a cost.

about two weeks ago
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To Really Cut Emissions, We Need Electric Buses, Not Just Electric Cars

floobedy Re:Container ships (486 comments)

I can see why we'd want to stick with bunker fuel for ships, since only ship engines can burn that kind of fuel. It takes huge engines to burn that kind of fuel. As you pointed out, no. 6 bunker fuel isn't liquid at room temperature so it's necessary to pipe the exhaust past the fuel tank in order to melt the fuel, so the fuel will flow into the engine.

Without ships, bunker fuel would kind of be a useless waste, since no other engines can use it. I suppose it could be burned for heat or electricity, but oil is an awfully expensive way doing those things.

I'm more familiar with the economic aspects of the ocean shipping industry, than the engineering side. I wonder if it would be possible to filter out some of the crap that comes out of the smokestack. That way ships could continue to use bunker fuel without harming the health of people around. Something akin to a catalytic converter on cars.

about two weeks ago
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To Really Cut Emissions, We Need Electric Buses, Not Just Electric Cars

floobedy Re:Everything old is new again (486 comments)

San Francisco has had a fairly extensive trolleybus network since the 1930s. Although only 15 bus lines are trolleybuses, those are the most crowded bus lines, so a significant fraction of bus traffic there is electrified.

It appears that diesel buses cost $450,000, and battery-electric buses cost $825,000, and trolleybuses cost $1m each. Trolleybuses last at least twice as long as diesel buses. The overhead wires cost $2 million per mile and last almost indefinitely, it appears, because I have never seen maintenance being performed on any of them, in contrast to roads and stoplights which are being repaired constantly, and buses which are being replaced often enough.

San Francisco has 300 trolleybuses for 15 lines, and each line is about 6 miles long. Thus the overhead wires cost $180m, the buses cost $300m, and the electricity costs $48m over 24 years. It appears that equivalent diesel buses would cost $270m and use $330m in fuel over 24 years, servicing the same routes (just using the numbers I read from an article and doing the calculation manually). It would appear that trolleybuses cost ~$528m for those routes and diesel buses would cost ~$600m. However, that's not taking into account financing costs etc, which would probably make the trolleybuses more expensive than diesel ones since the upfront cost is higher. Also, this is for routes in San Francisco which are only 6 miles long; the economics may change for suburban routes.

That said, it doesn't seem like the costs are very different whether we choose trolleybuses, diesel buses, or battery-electric buses. It may be slightly more expensive to go electric, but not much.

about two weeks ago
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To Really Cut Emissions, We Need Electric Buses, Not Just Electric Cars

floobedy Re:Container ships (486 comments)

The 15-30 largest container ships in the world (depending on who's estimates you're using) produce more pollution than all the cars combined.

The largest container ships have huge particulate emissions, but that's because there's no regulation on particulate emissions according to international law. It would be difficult to change that, because regulating ships requires an international agreement. That said, it should be done.

However, ships already have extremely low CO2 emissions per ton-mile. They are already extremely fuel-efficient. The largest ships have 1/15th the fuel usage and CO2 emissions per ton-mile as a tractor-trailer truck, and massively better than your car. If you drive one mile to the store to buy an article of clothing, you have emitted vastly more CO2 than was emitted by shipping it halfway around the globe by containership.

You want to reduce emissions? Pay for it to be grown locally instead of on the other side of the globe.

That will have almost no effect on your CO2 emissions.

about two weeks ago
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Is Storage Necessary For Renewable Energy?

floobedy Re:Law of Large Numbers (442 comments)

You missed the point of the post. Lovins was talking about unscheduled downtime like the wind not blowing, or a reactor scramming because of a tremor. He was claiming that renewables were similar to baseload power plants in that they both have unscheduled downtime. I was responding to that.

Of course there is also scheduled maintenance, but that's not what Lovins was talking about. That has no relevance to the discussion of whether storage would be required for renewables. If Lovins was talking about scheduled downtime then his point was even weaker.

about a month ago
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Is Storage Necessary For Renewable Energy?

floobedy Re:Law of Large Numbers (442 comments)

I don't think that's what he was saying. He appeared to be saying that no storage is required, aside from EV batteries.

about a month ago
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Is Storage Necessary For Renewable Energy?

floobedy Law of Large Numbers (442 comments)

I think the biggest mistake of the video, is when Lovins says that renewables are no different from baseload power plants, because baseload plants are down some fraction of the time also. He claims that power companies already compensate for downtime of baseload power plants by just having a few extra power plants. He claims that the same thing could be done with renewables.

That's just all wrong, in my opinion. It's a statistical error. Although baseload power plants are down 10-20% of the time, they are down at random. The downtime of any one plant is not correlated with the downtime of any other. As a result, if you have enough plants, then 10-20% of power generation is offline at any given time, as a result of the law of large numbers. That can be compensated for by building a few extra power plants.

With renewables, their downtime is not random. Their downtime is correlated with that of the other plants. For example, when the sun goes down, all solar panels stop working at the same time in a geographic region. Also, when the wind stops blowing (which can happen over a wide area), all windmills in that region will stop working at the same time. This is a much bigger problem than randomly distributed downtime.

If solar panels had randomly distributed downtime, and were as likely to generate power during winter nights as during summer days, then no storage would be required. We could just build more solar panels. This is because the randomly distributed periods of downtime of the solar panels would "cancel out" each other. However, it does not help to build more solar panels for the night time.

That is why renewables require storage.

about a month ago
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New Process Promises Ammonia From Air, Water, and Sunlight

floobedy Re:Ammonia fuel (117 comments)

Even if it only made 0.0001% nitric oxide and some kind of catalytic converter caught 95% of that, it would still destroy the environment faster than fossil fuels.

I doubt that. Burning a gallon of gasoline in an internal combustion engine produces about 1.5 grams of NOx, which is more than would be emitted by 0.0001% from ammonia combustion.

And that's if none of the ammonia ever escaped from vehicles, let alone the industrial production and transport.

Ammonia is a basic building block of life and is already produced in huge quantities by bacteria in the soil. Furthermore, it's produced in massive quantities by industry, at a rate of 150 million tonnes per year worldwide. That's more than 20kg per person, per year, worldwide, which is more than any other chemical. No attempt is made to confine that ammonia or prevent it from leaking into the environment. Quite the contrary, that massive quantity of ammonia is injected directly into the soil as fertilizer, or evaporates from window cleaner. The amount we are leaking into the environment right now, is vastly greater than the amount which would leak from the occasional defective fuel tank.

If ammonia is causing some dire environmental effect, worse than global warming, then I've yet to hear about it. I'm not saying you're wrong, but you'd have to provide some evidence for your assertion.

about a month ago
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New Process Promises Ammonia From Air, Water, and Sunlight

floobedy Re:Very amusing reading comprehension failure (117 comments)

Sure. Sorry to have offended you. I thought you were being snitty. I apologize for being aggressive in my response.

It's also probably harder to get the hydrogen out of the ammonia in secondary processes than from hydrocarbons - plus if it's fuel cell usage you do not need to go all the way down to hydrogen gas anyway.

I was originally thinking that ammonia could be used directly in internal combustion engines, as a replacement for oil when that starts to become scarce. Of course there are replacements for oil in most applications (plug-in cars and electrified rail), but there are some applications where a liquid fuel would be very helpful (such as remote construction equipment, ships, and so on).

There are very few combustible liquids which can be made out of the main constituents of air and water, and so wouldn't alter the composition of the atmosphere when burned. That's one reason I was excited about a process which produces ammonia using less energy.

about a month ago
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New Process Promises Ammonia From Air, Water, and Sunlight

floobedy Re:Very amusing reading comprehension failure (117 comments)

I was referring to how the above poster can find out about the relative danger of propane and ammonia and get some real understanding. Got it now?

I was referring to the paragraph I quoted, in which you were discussing making ammonia. I think you actually understand that.

You didn't know we were discussing making ammonia without fossil fuels, and you made a big fool out of yourself. As follows:

It doesn't come as ammonia. It comes as something like oil or natural gas, then you get hydrogen out of that, and then you make ammonia out of the hydrogen. It's an extra step

about a month ago
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New Process Promises Ammonia From Air, Water, and Sunlight

floobedy Re:Ammonia fuel (117 comments)

Don't guess or ask. LOOK IT UP... No, and for a very good reason. It doesn't come as ammonia. It comes as something like oil or natural gas, then you get hydrogen out of that, and then you make ammonia out of the hydrogen. It's an extra step

Why don't you try LOOKING IT UP by reading the actual article before commenting? The article (and the discussion) is about making ammonia without oil or natural gas, using a process other than Haber Bosch.

about a month ago
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New Process Promises Ammonia From Air, Water, and Sunlight

floobedy Re:Ammonia fuel (117 comments)

How would that be more dangerous than propane? LP gas would do exactly as stated above, if someone poked a hole in a fuel tank with their drill, they would get sprayed by rapidly evaporating fuel.

Ammonia is caustic and would cause a chemical burn on the surface of your eyes, unlike LP.

IMHO, this might be the way to have a hydrogen economy. If a nitrogen fixing process is easy and economical, making liquid ammonia is a lot easier and requires less pressure than converting water to hydrogen via electrolysis.

It seems much more sensible to use ammonia than hydrogen gas, because ammonia has handling and storage properties similar to propane which solves the major problem of hydrogen gas.

It makes a big difference if you can store something as a liquid and transport it through pipelines. That explains why oil sells for 10x more than coal, per BTU, and several times more than natural gas.

about a month ago
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New Process Promises Ammonia From Air, Water, and Sunlight

floobedy Ammonia fuel (117 comments)

Something not mentioned here is that ammonia is suitable as a fuel in internal combustion engines. Ammonia is liquid under modest pressures (like propane), is easily transported, and will burn inside an engine.

If we made ammonia out of nitrogen and water vapor, then it would become nitrogen and water vapor again when burned. It's a closed cycle that would not alter the composition of the atmosphere at all.

It probably wouldn't be suitable as a fuel for your car, because of safety issues (if you hammered a hole in the fuel tank, the fuel inside would flash boil and could shoot out into your eyes causing a chemical burn). However it would probably be fine for trains, airplanes, ships, and so on, where special handling procedures could be enforced and people could be required to wear goggles before working on the fuel tank.

about a month ago
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Tesla and Panasonic Have Reached an Agreement On the Gigafactory

floobedy Re:Cell and battery production in same plant (95 comments)

The amount of capital there has increased a lot over the last few decades. That implies fewer workers relative to capital, and higher wages for workers.

but there were plenty of places to squirrel that money away rather than pay workers.

When there's a scarcity of workers relative to capital, then workers have bargaining power. They can leave a job which pays too little for a job which pays more. It makes sense (ie is more profitable) for companies to pay more, otherwise they cannot attract enough workers to run their equipment. Competition among workers for jobs pushes wages up, when capital is abundant, just as competition between firms for customers lowers prices and pushes wages back down.

Companies in the US and western countries have always paid the lowest they can to their workers. Google has to pay $100k per engineer. If they paid only $50k, then all those engineers would go elsewhere and google would be no more. Labor is scarce in silicon valley, because there's more money than engineers. The relative scarcity of labor is what pushes the price of labor (wages) up everywhere, and is the only reason labor makes more than bare subsistence ($2/day) in any country. In countries where there is no capital (no factories, no investment money, etc), there is no labor scarcity relative to capital, and people actually make bare subsistence wages ($2/day).

about 1 month ago
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When Beliefs and Facts Collide

floobedy Re:Not surprising. (725 comments)

Sure it does. At least to those who aren't sure the earth is round.

No it doesn't. I was asking whether the procedure was logically valid, not whether some people think it's valid. The two aren't the same.

about 2 months ago
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When Beliefs and Facts Collide

floobedy Re:It's Okay (725 comments)

You must be an American if you equate liberal with socialist. In Europe, they tend to be the very opposite of each other.

In the USA, the left appropriated the term liberal and started using it to refer to itself in the early 20th century. It stuck. As a result, the word liberal now has almost the opposite meaning in the USA as everywhere else.

about 2 months ago
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When Beliefs and Facts Collide

floobedy Re:Not surprising. (725 comments)

For example some liberals are now promoting nuclear energey now that global climate change has proved to be a much bigger issue.

Some liberals do, but others don't. To me, it appears there's a small group of people who are reasonable and who really consider things. I would say that they are mildly liberal on average. Which does not imply that most people who are liberal are reasonable and really consider things.

about 2 months ago
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When Beliefs and Facts Collide

floobedy Re:Not surprising. (725 comments)

this is why people don't believe in AGW. Because every time that a proponent of it comes into contact with something that disagrees with their tidy view of the world, the first thing they do is lash out. And in the minds of a rational person, this simply screams "scam."

You don't believe in AGW because someone on slashdot was impolite in a comment? Which proves the whole thing is a scam to any "rational" person?

Try this. People who think the world is flat are fuckfaces. Does that imply that the round-earth idea is a scam?

about 2 months ago
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Ask Slashdot: How Often Should You Change Jobs?

floobedy Re:Job Hopping (282 comments)

Of course, I explicity stated that on resume.

EVERYONE states on their resume that all their prior projects were very successful, and that they're excellent employees.

If your employer was going by your resume and had no direct experience with your prior work, then they had no way of knowing what kind of employee you'd be. No one "minded" six month jumps on your resume because you code in ruby on small projects, and it's common among that group of people to jump around all the time, so nobody cared.

about 2 months ago

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