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Comment Re:RTFA this time (Score 1) 264

If you've dropped a bunch of trees you find you can land them wherever you want - provided you preset them with a pulley and come-alongs and use wedges. Doing it a few times, getting a course on it, and finding people who know what they're doing quickly get you to the right equipment, which is not just an axe. I've fit a tree between two others in a space where I had about 30 degrees to work with and not gotten hung up. But this goes back to all of the prepper gadgetry in the world is useless for someone who has no practice doing the tasks...

I don't use an axe, I use a woodsman's maul (I partially heat my house with wood in upstate NY). But I'd say (at 45) that the person who's suddenly trying to process their own 3 or 5 cords at age 50 is going to be disappointed when they take out their shoulder for a few weeks...

Comment Re:Reasonably stable but not fixed (Score 1) 692

And yet, there are plenty of working currencies where this is not the case. In fact, I worked in Brazil in the mid-90's right after the transition from the cruzeiro to the real. Before that, the cruzeiro lost value at a regular rate, to the point where gas stations agreed to hold post dated checks for say 20, 30 or 50 days as a form of price discount (I was doing market research for Texaco). At one point the rate of inflation was well over 80% a month. The economy continued to function, and this rate of decline was simply built into everything. So the rate of change isn't even an insurmountable problem as long as that rate of change is fairly certain.

This seems part of a larger campaign by Forbes against QE and Abenomics in Japan... QE is meant to cause mild inflation to prevent deflation. Abenomics is a more aggressive form of that where the Japanese have outright said that they will print enough cash to hit a minimum inflation target.

Comment Re:Interesting problem (Score 1) 200

Their modularity was set up to fail. I actually worked on a project for Boeing two years ago that was not Dreamliner related - ITAR protected so all I can vaguely say is it was a novel motor design for a crucial component that my former research adviser at RPI was the lead on. We were backfitting our new design into an existing motor compartment. As we got past the basic design, they then wanted an actual prototype to fit in a specific cavity, with some very specific power, speed, heat dissipation requirements and so on. We needed to match things like the mating spline, and we also needed our motor to lock into the existing space perfectly. Boeing did not own the original design, did not have access to the actual dimensions of the original motor - and the vendor in question didn't want to give the dimensions and was largely successful at saying no on this because it was their IP. Now granted we were academics working on something non-critical to their immediate success, but that tells you how far this process has gone for them in the wrong direction...

Comment Re:you can't store 3 days of fuel at high floors (Score 1) 162

Not during an earthquake (or even a flood - Christie turned off gas lines to towns on the NJ coast to prevent fires.) Diesel is also easier to transport by truck. Either solution can causes problems with fires. And yeah, yeah, I know that you can drop a match in diesel, but these are generators - so there's plenty of juice nearby. I did forensics after Irene on the failure of an emergency generator at a spillway at our plant, and in thinking about backup power we had to consider an electrical fire igniting the small tank near the generator and that then igniting the much larger tank isolated outside. The 500kW egen is going into a MCC which is connected to a transformer, which, in an emergency could be part of a fault, so in a disruptive emergency even a diesel tank could go up.

Probably a better solution if the space exists is solar with batteries... virtually no moving parts, and assuming it's well strapped down should be operational post disaster and will never need a refuel.

Comment Re:Cost (Score 1) 252

I was talking about the most efficient way to use a generator where you have to have a generator, and that would be off-grid or where UPS is needed.

On the 900MHz thing, it was a point to point tower. So they did not need to run fiber if they could get power. I think if they were running fiber there we'd have though of supplying power lines too.

On car inverters I am not talking about the _alternator_ or the regulator (which just rectifies the output from the variable frequency alternator, which is not 60/50Hz wall current, into DC at around 14V) - I was talking about cheap inverters that plug into the lighter socket on your car and provide 120V 60Hz (in the US) alternating current (AC) back for running crap like a laptop. Inverters are typically not built into cars.... I didn't think that would be unclear (since it was I'm not sure why I'm continuing to write the rest of this since you don't understand any of this stuff). The cheap inverters you buy having cheap switching components.

Lead acid batteries are not being considered in any serious way as an industrial storage mechanism. Pump hydro already exists, and we're trying out flow batteries (nasty chemicals but a close industrial loop), sodium sulfide cells (we've got a 6MWh storage system at a bus station in Long Island for time shifting), and even lithium ion if it can get an order of magnitude cheaper.

The reason power is cheap at night is because of technical limitations with our generation systems - Niagara runs because if it doesn't the water is gone. So for Niagara they build Lewiston pump hydro which allows that power to be load shifted to the next day. Most steam plants have a need to be started up and shut down gradually because of torsion on their shafts that go from multiple heat stages to the generator, so idling them entirely overnight is not practical. Nuke plants have the steam plant issues plus criticality requirements. All of these cause us to generate power at night which is what causes the cost differential. For generation that can be started or stopped quickly - gas fired turbines - this is not true. As more generation is made gas turbine the differential will disappear. This is actually an economic problem for the facility I work at. Anyway...

As for "safety"... I work in a 345kV power facility. I work with 500kW paralleling diesel e-gens for black start, in stators that run at 16.9 kV for 325MW power production, in a switchyard where 345kV lines are about 25 feet off the ground... I've also got solar at home. It is safer, if by safer you mean human safety... I don't have an arc flash distance of many feet on my 96VDC power. If you mean dependable or dispatchable I might go along with that.

You might be having a cognitive failure about what gives "redundancy". If you have a system that is 100% dispatched although you may have many many generators none of them is redundant. As it stands now on the grid (at least the part I know which is New York state) we have 18% excess capacity ready to go at any time, guessing what the power demand will be. However, the generation is all over the state, so there is the separate question of do we have excess transmission capacity, and at the moment that is usually barely enough for NYC metro. So a possible solution to the bottleneck is more local generation inside the NYC area. We're looking to do that with distributed generation (DG) - emergency generators at telecom central offices, other utilities, businesses with UPS, and yes, solar power. (There's also a plan for a 500kVDC cable from Albany to NYC under the Hudson... we currently run a 345kV underwater from one side of the Hudson to the other, and based on that I'd say the DG solution is... a tad less complex.)

As for "bad for the enviroment"... well, I'd say you really just don't want to know how the sausage is made... so you don't want to know about the underground PCB oil filled cables that still exist in many urban areas (because there is no viable alternative) or the SF6 gas breakers that we use, that can theoretically decompose into SF10 (a neurotoxin similar to phosgene) and is 23000 times more potent as a greenhouse gas than C02 (again, no viable alternative so we've got a waiver) or the lead, mercury and other crap you're currently getting from the coal plants... jeez, what stupid argument that is. Assuming solar has to be made as it is now from silicon wafers (which is not necessarily true for solar PV and has nothing to do with with concentrating solar), it is possible to do that more cleanly than burning coal... I worked in a chip fab in New Jersey that did gallium arsenide chip fab and we recovered all of that nasty crap like chloroform from the water and recycled it. Easy to do in a manufacturing facility, nearly impossible when you're in a combustion facility because of the amount of mass flow you're dealing with.

Btw, everything fails. Things with no moving parts tend to fail less. Where heating and cooling cycling make things that aren't supposed to move move they do fail more, but all things being equal the solid state devices work a lot better than their electo mech equivalents... which is why we can do things with switching components that we could never do before in motors, generators, statcoms, cap banks... so if you've got a solar facility, things are failing continuously, as they are at every power facility in the world, all of the time - but the failures are insignificant, unlike say when we have a water blockage from a broken flow switch paddle cause a heat exchanger to fail to cool oil on a bearing in a 325MW stator.... Or any one of the literally thousands of other points of failure from that 325MW generator - cooling systems, wicket gates, spherical valves that have thousands of valves themselves, electrical control systems, breakers... and I'm talking just a hydro generator which is dead simple compared to a coal plant, which in turn is far simpler than a nuke plant. If you are saying solar of any type has similar complexity you simply don't know what you're talking about. But that was clear.

Comment Re:Night? (Score 1) 252

Exactly. Also there are studies showing if you can integrate wind over a large enough area you basically get a flat 27% of nameplate capacity 99% of the time. Pump hydro (or another storage technology) just needs to be there on some scale to level the rest. And it's not like every gas turbine needs to be demo'd... we've typically got 18% spare capacity for dispatch in the US, I imagine it's the same in Europe (or more).

Comment Re:Night? (Score 1) 252

BG (Blenheim Gilboa) - the pump hydro I work at - does 16GWh.
This is its pond ("landlocked" body of water on the right):

As you can see, less than a square mile. If you look at the Walmart in nearby Cobleskill that takes up about 1/10 the land area (which serves probably a population of 10 or 20k, to think about whether this is a viable use of land). That's with about 1000 ft of head. But that's a lot. Here's Lewiston's:

Not a lot bigger, but actually has 4 times the volume and stores half as much energy total, given its head of 70-120 feet.

If you streetview in the area from the bridge you can see this. They took an area that is basically flat and used a marginal hill, and turned it into a reservoir with earth berms.

You need say 4 more BG's or 8 more Lewistons to cover the NYC metro (about 1/30th of US population) at night assuming solar PV only. If you add a mix of wind (which generates variably but does generate at night) over wide geographic areas, and concentrating solar power towers that generate at night, that greatly reduces the amount of storage needed to maybe double what NY State has currently. But just assuming solar PV, we've got an upper limit of say about two square miles (given upper and lower reservoirs) of surface per million people if you pick areas with ~100 feet of head. I think we might have ruled out Delaware. That's about it. But they've got Maryland.

We're 125 mi from NYC. We're also its black start facility. I.e., at worst 125 miles is a reasonable distance for this storage on the bulk electric system (but in reality hundreds of miles is certainly viable.) So in physical terms, you're wrong. The reason we're not currently doing this more is that natural gas seems to be cheaper and newer gas plants are almost as responsive as we are (effectively making them swing generation). When gas isn't $2 mmBTU this will probably no longer be true.

Comment Re:Night? (Score 1) 252

Don't know where you think you got your information on where pump hydro can work; Lewiston is a pump hydro at Niagara Falls... if you've ever visited the Buffalo area that's where the midwest begins. It's flat. The topology needed could be found in probably every state in the country (about 200 feet of head). That reservoir is almost entirely a man made creation (earth berms).

Pump hydro needs 1.3 MWh for every 1 MWh returned to the grid later. That is true end to end efficiency. It's comparable to any battery in efficiency, but is several orders of magnitude cheaper than batteries. We just LEM'd (life extension and maintenance) our pump hydro plant (16GWh delivered at 1.2GW) after 40 years in service at a cost of $135M.

Probably this plant was say $1.3Bn one time cost to build in 2012 dollars (based on Bath County being 50% bigger at $1.7Bn); I know we were about ~$100M in 1970. That's a one time cost... since we pump and gen we don't develop silting issues. We cost $11M to run annually, because we're a bureaucracy. We could be run full auto or at a much lower staff. Still, that's 16GWh at >$.001/Wh annually. This is why global capacity of pump hydro is increasingly quickly in areas with lots of renewables (the EU is adding about 30% more capacity by 2020).

But anyway, there's also molten salt Stirling engine solar, which can't ramp (because of heat constraints), and in effect can run all night... eliminating the need for any external storage.

Comment Re:Night? (Score 1) 252

I've no idea where you come up with 1MWh/person. That's ludicrous. For a household, 20kWh is sufficient... I've got 10kWh in my off grid capable system - SLA batteries, and I can run continuously in April - Sept off of 3440W of solar (I did this in June during a blackout and forgot to switch back for 4 days). With the other 10kWh and another 2kW of solar I could run all winter (I've got a backup generator that gets used during heavy winter storms). This is for me and my girlfriend living on a farm, with a refrigerator, freezer, well pump, electric ignite oil furnace and water heater, and electric dryer. Sealed lead acid has a daily use life of 3-5 years. I'm going to upgrade in a year or so to some form of LiIon, which will go 6000 charge cycles, about the life of my panels. That 6000 charge cycle life, btw, is the cycles until the charge capacity goes down by 30% - which matters a great deal on an electric car, but for a house means you add more batteries. Anyway, if you're keeping track that's 10kWh/person.

Industrial and commercial facilities are going to have industrial solutions, like pump hydro or flow batteries. I work at a pump hydro plant in upstate NY, and we store 16GWh of power, which is enough to run NYC metro for two hours under normal load conditions. We've got 150 people working here... because we're a bureaucracy... but we could do this with 10. There are dozens of locations that could be built for this up here (my organization runs another pump hydro in the state but we originally were going to build 12). In other words, there are no technical reasons NY state could not be 100% renewables, right now... it would probably double the cost of our electricity in the short run. OTOH, eventually we'd need no fuel.

Comment Re:It helps... (Score 1) 252

I remember reading about that... but when you think about it, once you've covered heat and electricity, you only need hydrogen for transportation. You'd be doing an electrolysis process of some kind to get it - but if I'm not mistaken a large percentage of people there live in metro Reykjavik, might as well just do electric cars directly for most of that.

Natural gas barely makes economic sense to transport as LNG (when you're all in for the tankers and other infrastructure); hydrogen is less energy dense than that and harder to deal with. If they were going to transport that energy content, aluminum is an excellent way to go. They also could in theory make natural gas/propane or another fuel like it with hydrogen to transport, but something solid like fertilizer is probably easier to do for the $. A high energy, value added export product is probably better than moving the energy to another location.

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