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This 'SimCity 4' Region With 107 Million People Took Eight Months of Planning

Smidge204 Re:Los Angeles (83 comments)

You are in a maze of twisty little subway lines, all different.

What happens if you try shouting "xyzzy" ? Or I suppose you'd need to translate it into Japanese first...
=Smidge=

6 hours ago
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$75K Prosthetic Arm Is Bricked When Paired iPod Is Stolen

Smidge204 Re:$75,000 for a prosthetic arm? (194 comments)

Seriously, they charge an arm and a leg for prosthetic limbs!

=Smidge=

3 days ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Some can be done - and is. Most is bull. (442 comments)

Sounds like you've got a much higher essential demand than what I figured on - desalinization?

Sorry for the delayed reply but I was re-running the numbers :)

When I was doing the calcs originally, I was really only interested in staving off power outages like we had with Sandy, which was about two weeks worth... not being completely off-grid. So focusing on hurricane season as a baseline, a 7kW system with 6kWh of storage would provide essentially unlimited off-grid capability from April through December *if* I managed my power consumption to essentials with just a little bit of creature comfort.

The winter months, however, result in a deep, DEEP deficit. I'd need 10kW of PV with 80 kWh of storage to be completely off-grid based on PVWatts data (with no power management). Of course, that's still relying only on Solar, and being completely off-grid was never the intention.

I don't pertain my own home is a good proxy for a regional or national grid, though ;)
=Smidge=

about a week ago
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Solar Plant Sets Birds On Fire As They Fly Overhead

Smidge204 Re:Drop solar heat for direct conversion (518 comments)

Except you can not exceed the solar power that hits the surface of the planet from the sun.

...which is a hell of a lot of energy. Collectively it's several orders of magnitude more than we as a species could ever reasonably harness, let alone use.

You could, for example, generate more kWh of electricity by putting 15% nominal efficiency PV systems on the roofs of ONLY single-family homes in the US, based on 2010 census data (67% of 130 million residences being single-family homes, with an average size of 2,400 sq.ft.).

In other words, we could hypothetically generate more than 100% of the electricity we need in 7800 square miles - about 5 Rhode Islands. That's at 15% nominal efficiency, assuming only 4 hours per day of operation. In other words, an extremely conservative value.

Just putting things into perspective.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Some can be done - and is. Most is bull. (442 comments)

What resources did you use to model these inputs? PVWatts I can understand for solar, but I'm not aware of any similar tools for wind and micro-hydro. Genuinely interested in what your data sources were.

Not that I'm yet convinced your model is applicable to a regional or national scale grid. Did you account for geographical diversity? Availability of these resources spread out over maybe 200-300 mile radius?

Also, peak demand of 5kW for 3 hours? My home has all electric appliances and I rarely, if ever, hit that... including the 3kW clothes dryer. This observation is neither here nor there, but that just strikes me as a high value.

To put things into perspective, I've been collecting minute-by-minute data for my own home's electrical usage (Got one of these things) and based on incomplete-at-the-time data it was looking like I could get away completely off-grid with a 6-7kW PV system and about 6kWH of storage. Less if I was smarter about how and when I used that power. Maybe your data doesn't have good enough resolution to really optimize the system.
=Smidge=

about two weeks ago
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Solar Plant Sets Birds On Fire As They Fly Overhead

Smidge204 Re:Estimates (518 comments)

1. Solar Thermal plants are built in the desert because that's where they have the most ideal operating conditions. The fact that there are more birds in forests than deserts is completely irrelevant because they don't build concentrating solar plants in forests.

2. We would expect the casualties to scale roughly with the number of plants, so is you had 1,000 such plants, that would be 1,000x the casualties. Still a drop in the bucket compared to the billions of birds killed by feral cats every year in North America.

3. You are right, of course, however you have to consider a cost-benefit as well. The cost of preventing bird deaths from not building concentrating solar plants (both monetarily and environmentally) versus, say, the cost of preventing bird deaths by doing something about the cat population. If saving the birds is the priority, then perhaps your dollar would be better spent on programs to reduce feral cat populations than preventing solar thermal plants from being built.

=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Some can be done - and is. Most is bull. (442 comments)

A single home isn't a very good proxy for a regional or even national scale grid.

With your house example, the only options are solar and generator. In reality you would have more than these two options. For example, add wind to the mix. You can argue that it's not 100% but it will cover a lot of run time at night, saving you battery capacity and reducing the required over-sizing of your PV system. Perhaps instead of 400% oversizing on PV, you only need 200% PV+Wind oversize.

Now add in something else... biogas perhaps. That covers you a little bit more and you can again reduce your oversizing.

Now add geothermal, hydro, solar-thermal (which works at night), and you start to easily fill in the gaps.

The US had 1,153 billion watts of generating capacity as of 2011 (Nameplate ratings, spreadsheet) and used ~3,797 billion kilowatthours that year. Naively we can say that if all our powerplants ran at 100% nameplate capacity, we could generate an entire year's worth of electrical energy in just about 3300 hours, or about 4 months... giving us a roughly 300% oversize on our electrical generating capacity *now*.

The key, of course, is that none of those plants are operating 24/7/365, and rarely are any of them operating at peak capacity.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:There is a big construction boom in Germany... (442 comments)

I'd also point out that Germany's accelerated decommissioning of nuclear power plants (all shutdown in 8 years) has a lot more to do with the coal plants than the increase in renewables.

Doesn't make sense: Coal power has actually decreased since 2000 when it was first decided that Germany should ween themselves off of Nuclear power, and the slight increase in coal power in the past two years is only a fraction of retired nuclear capacity, both in total and as a percent of total generation.

Germany's renewable energy push is what's filling that gap. If it wasn't for the nuclear phase-out, they'd probably have lost a third of their coal plants instead.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Expert?? (442 comments)

"A short distance" often being across national boarders.

=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Expert?? (442 comments)

That one project comes nowhere near the total scope of the upgrades planned an in progress. Despite the delays, work is in fact continuing even per your own article.

For a glimpse at the larger picture, consider:

http://energy.gov/oe/downloads...

Google search indeed, Mr. Coward.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:There is a big construction boom in Germany... (442 comments)

Germany is actually a net exporter - Their total gross production (Bruttoerzeugung insgesamt) for 2013 was 629.0 TWh, while their total consumption (Brutto-Inlandsstromverbrauch) was 596.0 TWh for that same year... resulting in a net import of -33 TWh, aka an export. Of course, these are year averages and they almost certainly import during some times of the year, and when they do most of it comes from France, Denmark, Sweden and Czech Republic.

I also do think it's somewhat unfair to use numbers all the way back to 1990. If we are interested in the impact of renewables, then it would be more appropriate to go back to 2001 at the earliest, when the Renewables Energy Act went into effect. That's when they started getting serious about it.

We can instead consider 1990-2000 as a baseline decade to compare the 2001-2013 decade to, in terms of growth by fuel type.

In the 1990-2000 decade, coal decreased and was supplanted by nuclear and natural gas. In the 2001-2013 numbers, total coal decreases slightly overall but nuclear drops considerably post-Fukushima. Natural gas ramped up to nearly double mid-decade but dropped back down to about 20% higher than it was in 2001. The resulting gaps between these decreased outputs and increased demand is filled entirely by renewables which nearly quadrupled in capacity to become the second largest energy source in the country, just a hair's width (15 TWh) behind soft coal.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Expert?? (442 comments)

Are you going to be one of those assholes who claims all energy is nuclear energy, because the sun uses nuclear reactions?

If so, please remove yourself from the conversation.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Expert?? (442 comments)

Actually, from what he presented, that is pretty much what would be required.

I don't get that impression at all. He makes a point about being able to predict loads and generation, which strongly suggests that the strategy is to plan well in advance where the power comes from and where it goes to.

Also, large power stations are located along strategically designed/placed transmission corridors and still generally only serve a regional load based on years of growth and demand. And don't confuse the marketing of power with the actual transmission.

Rather, transmission corridors are strategically located to link power plants to the grid. Power plants are built where they have the resources and infrastructure to support them - near waterways, for example, or close to their source of fuel.

Market is a total sum game and the buyers and sellers don't really control where the power comes from or goes, they just ensure enough is available regionally. The power generated closest to the user is what is used, even if it is credited for sale in a different area.

Not entirely true. Utilities (who are resellers) prioritize the lowest cost power sources first, and only buy more expensive power if necessary.

Here's a quick example, which I chose because it's germane to the overall topic of renewable integration.

https://www.youtube.com/watch?...

The power generated closest to the user is what is used, even if it is credited for sale in a different area.

Nope. A good portion of my electricity comes from a coal plant upstate, but there are gas turbine power stations just a few miles from here... they only turn on those turbines for peak shaving, because they cost more per KWh to run. You can tell if they're running or not because you can see the cooling towers steaming up from the highway.

Power comes from the cheapest available source, not the closest. Not all power plants operate equally, or even all the time.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:There is a big construction boom in Germany... (442 comments)

http://www.ag-energiebilanzen....

It's in German, of course. The key things you're looking for are the second and third rows (Braunkohle and Steinkohle) which are Lignite and Anthracite, respectively. Upport portion of the table is in TWh (Billion KWh) and lower table is percent of total generation by fuel type.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Expert?? (442 comments)

First, please realize that right now we as a country are in the process of rebuilding the entire power transmission system. That's happening no matter what, and it needs to happen no matter what.

In terms of the HVAC thing, which was just an example but one that seems to have stuck with you disproportionally so whatever... you would need to reduce the duty cycle to reduce power consumption, agreed? You would not have to turn it off for hours at a time - the entire concept here is that you could spread that reduction across a large population so that no single group bears the entire burden. We could, in theory, reduce electrical loads from AC units by 33% by disabling one in three units each for twenty minutes per hour.

As for "getting that power to flow the way he describes" - what is it you're imagining is happening NOW? You have power plants dotted all over the place, each with varying output, and power flows in any particular direction at any time. Nobody is proposing we instantaneously divert megawatts halfway across the country on a moment's notice - such a thing would be entirely unnecessary. However, diverting megawatts - even gigawatts - between substations and across counties and states is something that happens routinely right now, planned and unplanned. Nothing that can't be handled.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:There is a big construction boom in Germany... (442 comments)

Yes, a boom in coal plant construction... I guess that explains why Germany's coal generating capacity (hard coal + lignite) is down nearly 5% over the past ten years... all those new plants they've been building.

Any new plants they have been building - mostly to replace older, decommissioned ones - have been having problems because the cost of power has dropped significantly since construction began thanks to the glut of wind and solar. All that, despite reducing their nuclear generating capacity by nearly 44 TWh/yr after the Fukushima meltdown.

As for subsidies... have you accounted for the subsidies that current fossil generation gets? Land rights, construction cost subsidies, operational cost subsidies, environmental remediation subsidies... to make an indirect comparison, there's a reason the rest of the world pays three or four times more for their energy than the US does - subsidies.
=Smidge=

about two weeks ago
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Is Storage Necessary For Renewable Energy?

Smidge204 Re:Expert?? (442 comments)

He completely ignores the importance of local load differences, and seems to assume there is a loss-less, instantaneous transfer of energy across the national grid, both transmission and distribution channels, with no limitations.

Does he? His only claim here is that both supply and demand can be predicted, and that these can be choreographed to optimize utilization. He mentions that current power generation technologies are not available 100% of the time and proposes that the predictable variability of renewable power would be functionally no different. Nowhere does his proposal require loss-less, instantaneous, unlimited transmission of power.

He also doesn't get that even at a local level things like AC compressors are already averaged out and that delaying the timing of starts really makes almost no difference at the neighborhood level, much less a town level.

How are, for example, all of the AC units in a particular neighborhood "averaged out"? That makes no sense. There is no communication between these units. It's also not a matter of delaying the start times, it's a matter of remotely disabling them entirely - across entire neighborhoods - to shave peak demands.

Its nice to completely ignore realities like overall cost.

So what ARE those costs, versus the cost of business as usual? Just because the article doesn't go into that kind of depth does not mean it hasn't been considered at all.

Its nice to not realize that industrial areas have a significantly different profile than urban areas, and that rural areas are vastly different.

Largely Irrelevant here; Of course different regions are going to have different characteristics, but you can still model and predict the behaviors of each region and the system as a whole. Other countries manage to do it, and there's no reason the US can't do it as well.

Its nice to call yourself and energy expert and get submitted to slashdot by those that believe you just because they want to, or because you fall in line with their agenda.

It's also nice to rant about things you don't agree with while not providing any of the expertise you criticize others for claiming.

Credible experts are people who understand what they know, and what they don't know.

Unlike, say, Slashdot users who of course are experts in everything...
=Smidge=

about two weeks ago
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Normal Humans Effectively Excluded From Developing Software

Smidge204 Re:Cry Me A River (608 comments)

Normal humans are excluded from a lot of things.

1. Olympic Gold Medal
2. 5x Jeopardy Champion
3. Professional Concert Pianist
4. Bolshoi Ballet
5. Supermodel

Our technologically advanced society will not fall into ruin if nobody ever becomes a 5-time Jeopardy Champion ever gain...

On the other hand, guru-level engineers are considerably more important.
=Smidge=

about 1 month ago
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Unintended Consequences For Traffic Safety Feature

Smidge204 Re:How about a sign (579 comments)

For traffic lights that are really long, and I'm familiar with, I will often turn my engine off since I know I'm going to be going nowhere for >1min. The timer on the crosswalk sign gives me plenty of warning so I can start the engine and be ready to go.

Of course, this is hardly any different from just looking at the traffic light for the opposing direction - most of the time you can see it change to yellow, then red, and you know a few beats later your way will turn green. Drive the same route for more than a few days (e.g. your typical commute) and nearly anyone will know how the lights behave throughout the day and be able to predict them.
=Smidge=

about 2 months ago

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More info from Nissan LEAF Tour

Smidge204 Smidge204 writes  |  more than 4 years ago

Nissan's national tour of their new electric vehicle offering, the LEAF, recently completed its last stop at the Liberty Science Center in Jersey City, New Jersey. Nissan representatives were on hand answering questions about the car and their plans to bring it to market, and I was able to collect a lot of good information which the Slashdot community might find interesting and useful. Below is a fact-dense summary of everything I was able to tease out of them.

The LEAF is a 5 passenger, 4-door hatchback bearing a striking resemblance to the currently available Versa, although once you see it in person it becomes obvious that the car is an entirely new platform designed specifically as an electric car, rather than a tweak of an existing vehicle. First impressions, shared by other visitors I met, was the vehicle was much bigger than the phrase "electric car" brings to mind.

The LEAF's technical specifications are no less impressive, though still somewhat tentative as production is not scheduled to begin until this fall:

80kW (107.3 HP) synchronous AC motor producing 380 ft-lbs (280Nm) torque. 24kWh worth of air-cooled, modular (48 modules, 192 cells total), laminated lithium-magnesium batteries located under the floor and rear seats giving a listed driving range of 100 miles (as tested under LA4 methods, aka "the city test") and a max speed of over 90MPH (144KPH). Curb weight is approximately 3300 pounds (1500 kg) including the 480 pound (217 kg) main battery pack. The main battery is rated for full capacity from -30ÂF to +100ÂF (-34ÂC to +38ÂC) and has a life expectancy of 7 to 10 years, with "end of life" defined as capacity degraded to 70% of the original. The LEAF comes with four wheel disc brakes and two stage regenerative braking which can recover up to 30% of the vehicle's kinetic energy in most situations. Brakes are hydraulic (w/ electric booster) and steering is drive-by-wire. A cable operated parking brake is also included.

Power from the main battery is cut in the event of an accident for safety. It is not known if a separate kill switch for disconnecting the battery manually will be provided.

The LEAF is capable of three charging options: it comes standard with a 110v outlet charging cord, allowing you to plug your car into any 15 amp outlet for charging via the charger incorporated into the vehicle itself. Charge time for 0% to 100% is estimated at 16 hours using 110v. Alternatively, you can charge the car using 208v using a required "charging station" in about 8 hours from 0% to 100%. Both of these methods use the same J1772 socket, recently made a standard by SAE International, meaning this and all other vehicles that plug in to charge will use the same connectors.

The 208v "charging station" is, I was told, simply a surge protector and over-current protection device which must be professionally installed and certified for code compliance and liability issues. While Nissan plans to offer Nissan-brand charging stations, you will not be obligated to buy one as the 110v charging cord is supplied with the car. Charging stations may also become available from third party manufacturers since they do not contain anything proprietary, and like the J1772 connector should be compatible with any plug-in car on the market.

The third "quick charge" option uses 480v connection through a second, dedicated socket and connector and can charge a dead battery to 80% in just under 30 minutes. Quick charging is halted at 80% to prevent damage to the battery. There are no plans to offer quick charging stations to the general public since very few houses have 480v electric service available. Nissan is working with private companies to install both 208v and 480v public charging stations for general use.

The LEAF includes, as standard equipment, an integrated GPS navigation system which helps you plan routes that pass near by public charging stations. Monthly updates to the navigation system will be provided for free. Also included is 3G communications which allow the on-board computer to send and receive data via the internet. The computer can be configured to send e-mail status updates, and various features such as charging schedules and heat/air conditioning operation can be done remotely via internet connected PC or cell phone. When asked about privacy concerns, the reps said that Nissan plans to collect usage data via an opt-in program only from their initial test users. There are no long-term plans to monitor driving and charging habits.

Other standard features include heated seats and steering wheel, air conditioning, power locks and windows, AM-FM/CD stereo with aux input for portable players, keyless entry/startup and 24/7 roadside assistance. All vehicle lights are LED. Features that are not offered include power seats, sun roof and spare tire.

The "ignition" is a large power button located just below and to the right of the steering column. The rep said there is no delay turning off - meaning you don't have to hold the button - but she never tried it "at speed" so it is unclear exactly what will happen if you turn the vehicle off while driving.

There is no set price yet, but I was given a target range of $28,000 to $33,000 before rebates and incentives. Official pricing is due to be announced in April. At present, the LEAF qualifies for $7,500 in federal tax rebates, along with 50% of the install cost for the 208v charging station (up to $4,000). Additional rebates and incentives may be available from your state government as well. Nissan plans to offer buy and lease options, but they can not offer battery-only leases due to federal laws. The federal government considers the battery to be part of the drive train, and it is illegal to sell a car without a functioning drive train.

Production is scheduled to start in Japan this fall, with a portion of those vehicles being imported to the US for test markets and early adopters. Official announcements are scheduled for December of this year. By 2012 Nissan plans to have a vehicle and battery manufacturing plant operating in Tennessee with a capacity of 150,000 vehicles and 200,000 battery packs per year.

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