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• Since First Solar must purchase energy to run its manufacturing process like anybody else, your answers can be roughly derived from the numbers of $1 per watt in manufacturing costs. Lets assume that, overall, the very cheapest available energy is used throughout the process (mining, refining, manufacturing, etc) to present a worst-case scenario. Let's call it $0.01/kWh. That 1 watt of panel will take 100,000 hours of full sunlight to make up its energy investment in the very worst case....or roughly 35 years in a almost-always-sunny place like the desert South West (assuming 8 hours of full sun per day on average). If you consider that it is displacing more expensive power generation (lets call it $0.10/kWh), then the pay-back is only 3.5 years. On average, you could probably call it 10 years and build a legitimate ROI case from there. In reply to: "First Solar: 1 billion watts served"

  December 16, 2009

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• running the computers at 100% utilization all the time can arguably shorten their potential lifespan depending on the cooling systems and other factors (and thus the depreciation rate of the equipment is affected due to an accelerated MTBF). While perhaps difficult to pin down quantitatively without carefully controlled statistical analysis, the effect is definitely non-zero.
  
  And @sittingincomputerclass..yes, running the computers like that does increase their power consumption...and THAT effect is easily computed/measured into dollars and cents. In reply to: "Man loses job after searching too hard for aliens"

  December 1, 2009

  0 replies

• @Magallanes
  
  The nearest star is a hair over 4 lightyears away, actually. And while SETI seems impractical due to the distances (and "time-shifting") involved with the potential signals...detection of such signals (and yes they would have to be pretty "loud"..but a beacon created for the purpose of remote detection would be so by design) would be a monumental moment in human history in both scientific and religious/philosophical terms as we would know (or have very strong evidence for) that we were not "alone" in being the sole intelligent life around. Not that we would be able to act on that knowledge by establishing 2-way synchronous communication, but just knowing would be a pretty huge thing IMHO. That being said, using spare computer cycles for Folding@home seems to be a much better use of resources as that project is aiming to solve here-and-now medical issues. In reply to: "Man loses job after searching too hard for aliens"

  December 1, 2009

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• The 40 mile figure is based on the tail-end (@ 10 years) capacity of the battery back, not the capacity at sale.
  
  I agree that the price is fairly high given the current competition and gas prices..but so it goes with all 1st gen technology. Calling it a "failure" is premature at best. It is a product aimed at early adopters in order to spur further development of products aimed at the mainstream. As such, it is in a very good position.
  
  As for your suggestion of a 30hp engine and a small battery..good luck with that if you live in mountainous areas. The size of the engine and the battery pack in the Volt were chosen to be practical in the largest percentage of the roadways in the U.S. as possible..your suggestion basically restricts you to flat-and-level. I'm glad you weren't one of the lead engineers on the project. In reply to: "Q&A: Will the Chevy Volt make money for GM?"

  October 30, 2009

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• congratulations for completely missing the point! In reply to: "Plan connects U.S. grids to transport solar, wind"

  October 13, 2009

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• Well 1) Let's wait to see the plan before we arbitrarily shoot it down. 2) Feds bulldozing state's rights? It's the state of NM that is a major partner in this..nothing needs to be "bulldozed". And 3) Have you ever been to Clovis, NM? I assure you..there's not much there and thus not much in the way of a NIMBY factor unless the cows get a vote. And just as in Roscoe, TX...I would imagine all the ranchers whose land is utilized in such a project (for the transmission lines coming in from the 3 grids) will probably get a royalty check so I'm pretty sure they'll get on board. But, like I said, lets wait for the detailed plan and go from there. In reply to: "Plan connects U.S. grids to transport solar, wind"

  October 13, 2009

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• With the high-voltage rapid charging tech many companies are now talking about...20 minutes would get you a pretty decent chunk of juice. Depending on what they charge for it (perhaps nothing), it would be well worth your while to take advantage of it even if it didn't bring your batteries all the way up to full. In reply to: "Who will pay for the electric 'gas' stations?"

  October 9, 2009

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• In many places across the world, when you go to a McDonalds (to use the example provided in the article), your receipt has a code on it which allows access to a restroom stall. This is to guarantee that only paying customers have access to the restrooms. It seems trivial to extend this concept to charging stalls for your car with the juice automatically starting after the food is paid for (so you could hook it up physically before you walked in the restaurant, but nothing happens until you pay for your food). You could have something like the first 10 minutes (or perhaps first kWh) complementary with purchase, and then you could "upsize" your charging (again, time-based or energy content based, whichever makes sense from a business/marketing standpoint) at the time of purchase just as you would upsize your fries and drink.
  
  The hardest part, in my opinion, would be getting people to respect the "electric cars only" parking in those slots with the chargers...the rest seems pretty easy with today's technology. In reply to: "Who will pay for the electric 'gas' stations?"

  October 9, 2009

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• I should caveat the above as "To carry the same amount of power AT THE SAME PEAK VOLTAGE"...
  
  Obviously, if you are comparing a 12V DC system to a 120V (170V peak due to RMS) AC system, the AC system wins the "conductor race". But the opposite would be true...a 120V DC (and to a greater extent a 170V DC) system would perform vastly better in that respect than a 12V AC (17V peak) system.
  
  In a comparison between a DC system to AC system at the same peak voltage (eg say the 170V peak that is common in the U.S. for the 120V RMS delivered power), the DC system wins hands-down as I previously mentioned. In reply to: "Solar village begins to bloom on National Mall"

  October 8, 2009

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• Joe,
  
  Your theories on the advantage of AC vs DC due to conductor thickness are backwards. To carry the same amount of power, DC conductors can be thinner due to the skin effect that AC experiences (the impact of which is determined by a number of factors), as well as the lower peak voltage needed to carry a given wattage rating due to the lack of the RMS part of the equation (thus allowing for lowered insulator requirements). For a given conductor cross-sectional area and peak voltage, DC will actually have a smaller drop in voltage per unit distance for a given delivered amount of power because the current flow will be smaller and DC does not suffer from RF energy leaking like AC does.
  
  AC has some advantages as well, but relative conductor losses are not one of them. The largest advantage is the ability to easily and economically step up/down voltages with a transformer...though as you mentioned even that advantage is being eroded with ever-better DC voltage steppers.
  
  You are correct, however, in mentioning the dearth of DC appliances that are available being the main drawback of DC power to the home. In reply to: "Solar village begins to bloom on National Mall"

  October 8, 2009

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