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Comment: Re:Very unlikely to be triggered in the field (Score 1) 214

by sphealey (#49600345) Attached to: Long Uptime Makes Boeing 787 Lose Electrical Power

The entire world isn't the US/Japan/EU. While most airlines outside that region who operate 787s run tight operations (Ethiopian for example is often mentioned as very well-run with a strong safety culture), there are a few who do not.

That said, in the few instances where less organized airlines have managed to acquired 787s they are probably being shut down 2-3 times/week much less every 9 months.


Comment: Re:This again? (Score 1) 420

by Bruce Perens (#49598949) Attached to: New Test Supports NASA's Controversial EM Drive

OK, I will try to restate in my baby talk since I don't remember this correctly.

Given that you are accelerating, the appearance to you is that you are doing so linearly, and time dilation is happening to you. It could appear to you that you reach your destination in a very short time, much shorter than light would allow. To the outside observer, however, time passes at a different rate and you never achieve light speed.

Comment: Load Leveling (Score 1) 499

by sjbe (#49596665) Attached to: Tesla Announces Home Battery System

The battery is good for two things:

You missed one. A third thing it is good for is grid level load leveling. If there is storage capacity in the power network you can significantly reduce the effect of fluctuating demand to the companies generating the power. Coal and nuclear plants take a while to respond to changing demand. If demand spikes then the power stations have more time to react.

Comment: Where we need to get to call this real (Score 1) 420

by Bruce Perens (#49596461) Attached to: New Test Supports NASA's Controversial EM Drive

Before we call this real, we need to put one on some object in orbit, leave it in continuous operation, and use it to raise the orbit by a measurable amount large enough that there would not be argument regarding where it came from. The Space Station would be just fine. It has power for experiments that is probably sufficient and it has a continuing problem of needing to raise its orbit.

And believe me, if this raises the orbit of the Space Station they aren't going to want to disconnect it after the experiment. We spend a tremendous amount of money to get additional Delta-V to that thing, and it comes down if we don't.

Comment: Electrons are fungible (Score 1) 499

by sjbe (#49594027) Attached to: Tesla Announces Home Battery System

The grid is not only maintained, it is also "operated". And that cost is not fixed but depends on the amount of power you transport.

Which is exactly what I said. Consumption (delivery) of power is a variable cost. If you consume no power because you have solar panels then no cost is incurred to the power company. Maintaining the infrastructure to deliver that power is largely a fixed cost so if an end consumer wants to tie into the grid they should rightly incur their share of the cost of maintaining that infrastructure.

I buy power at point A and sell it at point B, for that I need to transport the power over minimum 2 grids, a transportation grid from A, reaching close to B and a distribution grid at B, where the customer is connected.

Those are variable costs as they vary with units of power sold.

However: there are transportation losses, 5% ... 7%.

Simply part of the variable cost of power sold. Similar to shoplifting losses for a retail store. It's a known part of the cost of the product being sold. If they don't sell the power then no cost is incurred to buy it or produce it.

The grid loss has to be compensated by the grid operator, hence they are the ones who have reserve power plants and balancing power plants attached to the grid. And hence transporting power over a grid costs nearly the same amount as producing it.

What price the power company pays for the power delivered to end customers and where it comes from is largely irrelevant to the end customer. Electrons are fungible assets. Whether they produce it themselves or they buy it on the spot market or buy it on contract isn't important as far as you and I are concerned. They are paying for some fixed amount of grid maintenance and some variable amount of power delivery regardless of who actually produces the power. The equation doesn't change just because they buy the power from a third party.

Comment: Disingenuous cost accounting (Score 1) 499

by sjbe (#49592999) Attached to: Tesla Announces Home Battery System

If you put enough PV on your home, you can eliminate your electric bill. At which point, many utilities argue, the costs of maintaining the grid (that's rolled into your electric bill, but not as a separate line item) are covered by the less-wealthy.

I'm a certified cost accountant in my day job and this argument falls flat if they are actually charging in a rational manner for their services. The cost of maintaining the grid is (or should be) a separate charge from the cost of the electricity you actually use. Maintenance is a (roughly) known fixed cost, usage is a variable cost. If the person maintains a connection to the grid it is a fairly straightforward proposition to charge them a flat rate for the privilege which covers their portion of the infrastructure maintenance. Infrastructure maintenance cost is not generally strongly dependent on usage for electricity so they don't have wear issues as a general rule. If they aren't separating charges like this then they are Doing It Wrong.

The only reason the utilities have to be upset is just that they aren't making as much money.

Comment: Disinterest and fear (Score 1) 67

by sjbe (#49588181) Attached to: Apple, IBM To Bring iPads To 5 Million Elderly Japanese

I dont know whether it is cost, learning difficulty, or conservativism.

In my experience it's mostly disinterest and/or fear. They haven't needed it most of their lives, they are quite set in their ways and they aren't terribly interested in learning something new. They will loudly proclaim how they "just don't get this stuff" but usually that's an excuse for not wanting to learn because their brains work fine. If it's really easy the might give it a whirl but if learning requires real effort they usually cannot be bothered.

The guys who own my company are about 70. They are quite intelligent but will repeatedly ask me the same questions ("how do I print this", etc) despite having been given the explanation plenty of times. It has nothing to do with their brain but they just don't care about the answer so they don't bother committing it to memory. Easier to just ask someone else who has bothered to care.

Comment: Re:ISPs absolutely deserve regulation (Score 1) 430

by sjbe (#49586363) Attached to: Rand Paul Moves To Block New "Net Neutrality" Rules

If you have a "choice" of one ISP it's because your local Franchise Authority (your town/village/city board usually) has opted to only grant a franchise to one company.

Wrong. It is because of economics. There simply isn't enough business available to support a competitive set of ISPs where I live. I live in a town with about 10,000 residents on the distant outskirts of a major metro area. There is zero chance that any new ISP would be able to win enough business to make the investment worth their while.

I have a phone company and a cable company both of which could offer service to my residence but do not offer equivalent service. The phone company technically provides DSL service to near me but it is FAR slower and economically a non-starter. The only other option is to go LTE through the mobile phone providers but due to data caps that too is an economic non-starter. It's just not competitive at all and there is no reasonable prospect of it becoming so no matter what my local government does.

Even if my locality were to invite every ISP in the world to come play the simple fact is that in the semi-rural area where I live there isn't enough business to support more than one or two lines to my house. Since the government does not require the ISP to be separate from the company providing the wire to the house then there is effectively no way for any new entrants to make money. The capital costs of building out their own network are astronomical so there has to be a pretty substantial company backing it and enough business they can capture to make it worth their while.

Don't blame the ISP for your local politicians' inability to stand up for you.

I don't. The economics of the situation are plain and a regulated monopoly will get me better service than any feasible set of competitors where I live. The best case I could realistically hope for is a duopoly which isn't a prospect to get excited about.

Comment: ISPs absolutely deserve regulation (Score 1) 430

by sjbe (#49585781) Attached to: Rand Paul Moves To Block New "Net Neutrality" Rules

Good FCC regs would get the hell out of the way of the ISPs who -- really -- have done nothing to deserve what they're getting.

Who is your ISP? Mine is Comcast and they very much deserve to be regulated rather heavily. I have a "choice" of precisely one ISP where I live and I can assure you that they abuse the privilege. I want them to provide me a pipe to my house and get out of the way. They do not need to be in the business of determining what speed packets should be delivered to my location. Particularly if they start prioritizing their own content (Comcast owns NBC for instance) over what I actually want to watch. There is NO benefit to me as the consumer for my local telecom monopoly to not be regulated. None.

FORTRAN rots the brain. -- John McQuillin