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Submission + - A second life for EV batteries->

lfp98 writes: When I converted my EV from lead to lithium, I moved the tired old lead batteries to the basement for backup during power outages. Both GM and Nissan are now planning to do the same on a massive scale, developing systems for utility-level power storage based on used Leaf and Volt battery packs. Both companies already have in-house pilot projects, and plan to ultimately market the systems to power companies. Even after 100,000 miles, these batteries retain up to 80% of their original capacity. Though too weak for automotive use, they can find a second life in the much less demanding role of stationary power storage, where the power/weight ratio is nearly irrelevant and the rapid charge and discharge cycles that degrade the battery's performance rarely if ever occur. Finding a new use for old batteries would effectively lower the lifecycle costs and carbon footprints for both EVs and renewable power.
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Comment Niche products for the well-heeled? (Score 1) 356 356

"solar panels and electric cars . . . . remain niche products for mostly well-heeled customers." I'd agree that might be accurate for Musk's cars, but for EVs and solar panels in general it's at least misleading if not flatly false. The people I know who drive electrics aren't particularly wealthy. Other than Teslas, EVs now sell, after the rebate, at roughly the average price for a new car in the US, about $30,000. Decent used ones can be had for $12-15,000. Plenty of middle-class families manage to come up with that much and more for a car, so the implication that EVs are out of reach of the masses is just wrong. And unlike many tax breaks, the EV credit doesn't increase just because you're in a higher tax bracket, everybody gets the same $7500. A solar panel array actually costs less than the average cost of a new car, even before the tax rebate. And, both EVs and panels actually save the purchaser money in the long run. If they skew toward wealthier folks, it's probably because highly educated people are buying them. As far as states bidding for manufacturing facilities with millions in subsidies, that's now pretty much standard procedure. With China and others subsidizing manufacturing, we have to do it too, or else cede all production to others. When the US went for free trade and let China into the WTO, that's what we were committing ourselves to.

Comment HVDC (Score 1) 597 597

Seems to me the author is understating his own argument, and missing the point, to some extent. The devices he excludes ("Appliances like electric ovens, electric water heaters, and air conditioners will [still] require 110VAC") are precisely the ones that take most of the power, probably 80% in aggregate. So, if you want significant savings, those would have to be DC as well, but it would have to be 220VDC or at least 110VDC, because for 12 volts you would need at least finger-sized copper bus running all through the house. In fact, the most efficient new air conditioners / heat pumps (e.g. Daikin Altherma) run on DC, i.e., they convert the AC to DC which then powers inverter-controlled synchronous motors. A water heater, even an existing one, could just as easily run on 110/220 VDC, you'd just need to replace the control unit. What you'd probably want is a system with at least 2 voltages, say 24V and 220V, each with its own battery charged by its own solar array, so you don't need to do DC/DC voltage conversion (which also has losses though probably not as much as an inverter). Most of the house would only have 24VDC wiring, 220VDC would only go to the kitchen and utility room, just as it does now in AC systems.

Comment Samsung T245G (Score 2) 313 313

Pretty dumb phone, although with some effort you can browse, text, even take crude pictures. If you choose the right plan at Tracfone and keep to less than 1 minute a day, you can get by for ~$5 a month. Of course at home I wouldn't use anything other than my genuine Western Electric rotary-dial.

Comment Re:Wind power is not the answer. (Score 1) 256 256

The noise is not from bad bearings but simply from the blades whooshing through the air. I don't have first-hand experience but those who live near turbines say it can be pretty severe. I can see a place for turbines offshore and in the wide-open spaces of the Great Plains where there is ample wind. But in the more populated east and west coasts, the noise and visual pollution just aren't worth it, especially when the wind is so intermittent. The few remaining undeveloped spaces there deserve to be left alone. Are we to have every Appalachian mountain ridge dominated by turbines even larger than the monsters already in use? In the long term, PV solar with battery storage is the only sensible solution. It's a little too expensive now, but in 10 years if not 5 years it will likely be comparable to wind and cheaper than any fossil fuel. By the time mega-turbine wind gets going, it will already be obsolete.

Submission + - Legal dispute clouds future of crowd-funded solar farm

An anonymous reader writes: Having exceeded their goal of $300,000 and raised over $440,000 for a crowd-funded solar farm (http://www.gocloudsolar.com/news/), CloudSolar is locked in a legal battle with crowdfunding site Indegogo. The CloudSolar page on Indegogo has been taken down (https://www.indiegogo.com/projects/cloudsolar-own-solar-panels-no-roof-required--4), without explanation. In dueling emails to contributors, Indegogo cites unspecified violations of its terms-of-use, while CloudSolar insists that Indegogo thoroughly reviewed and approved their project and is now changing the rules retroactively. Apparently, the two sides are still negotiating but meanwhile CloudSolar has sued Indegogo, which remains in possession of the funds. CloudSolar had garnered extensive press coverage for their innovative financing model, wherein crowd funders would retain legal ownership of individual solar panels on the farm and receive periodic payments from the sale of the power they generate http://www.bostonglobe.com/bus.... Some “Apollo”-level funders put up $9000 each for a group of 15 panels, which is now in limbo.

Comment Children should wear reading glasses (Score 1) 144 144

Or at least not wear their "normal" prescription when reading. I know for sure what happened to me. I spent plenty of time outside but I read a lot of books too. I acquired nearsightedness by about 5th grade, so of course they gave me corrective lenses to restore 20/20 vision, i.e., perfect focus at something 20 feet away. That meant that for reading, my eyes had to focus even closer than they would otherwise, in order to compensate for the glasses trying to focus farther away, so I got even more nearsighted, got stronger corrective lenses, and it just snowballed. By the time I finished college, I had corrective lenses of roughly -5.0 left and -4.0 right. Now, with no glasses, my natural, relaxed focal distance is about 4 inches in front of my face, anything farther I need glasses. I realize now what I should have done is at least take off my corrective glasses for reading and any close work.

Comment Osteoporosis (Score 1) 304 304

In my younger years it never occurred to me that I would some day be too old to bicycle, and certainly not in my 60's, but now I realize it is simply too dangerous. Given my bone density, typical of an 80-year-old, a fall, even a minor one, would likely be catastrophic. My case is unusual, but the majority of 60+ seniors have some degree of osteoporosis and most of them probably shouldn't be biking. My father-in-law biked well into his 70s, but had a fall - on a bike path - and was never quite the same after that. I'm just kind of surprised no one talks about this much.

Comment What is the goal? (Score 1) 273 273

So far, efforts to increase longevity and slow the aging process have indeed extended the number of years over which people can still be productive, healthy and independent, but they have extended by almost as much the subsequent period of decline during which people are still alive but largely unable to care for themselves. Proportionally, we are spending a larger fraction of our lives in disability than ever before, thanks to modern medicine. One can make a pretty good argument that we have already gone too far in increasing human lifespan.

Comment Make your own prescription (Score 1) 464 464

Progressive lenses take the prize for most useless invention (apologies to Mr. Franklin). To use the reading portion of the lens, you have to cock back your head uncomfortably or put the reading matter down on our chest. It's far easier to just switch glasses when you need to. For computer viewing, they're completely useless. For distance vision, I need very strong corrective lenses (approx. -5.0 left and -4.0 right). Progressive lenses are made by simply adding approximately +2.0 to the reading portion of the lens. So I just added +2.0 to my prescription ordered full lenses with -3.0 left and -2.0 right, resulting in a focal length of about 2 feet, perfect for computer viewing, which is what I got them for, but I'm finding that they are fine for almost everything I do in life, which generally involves focusing on things at roughly arms length. I have a pair with the original prescription specifically for distance vision, but the only time I use them is for driving, and occasionally for watching seminars.

Comment Were they really helped? (Score 1) 739 739

I'm not saying they're right, but a lot of people who bought policies or even were enrolled in expanded Medicaid don't necessarily feel that they were "helped". They rather liked the old system where you get along with no insurance and minimal healthcare for much of your life, wait till you get a catastrophic illness in middle age, and then throw yourself on the mercy of the system, which is forced by law and tradition to provide care regardless of ability to pay. Then you just muddle along for a few years until Medicare kicks in. It was a chaotic, unfair, inefficient, expensive, and convoluted system that we all paid dearly for. But was it really that much worse than the Rube Goldberg contraption set up by ACA? Many people don't think so. And only the most deluded liberals ever thought there would be any political payoff from grateful enrollees.

Comment Re:They should be getting jobs at univeristies (Score 1) 283 283

It's not a generational thing. Rather, universities are only hiring people who already have at least one grant, and these days most such people are already middle-aged. Hiring a new Assistant Prof straight out of a postdoc, no matter how prestigious their publications, is just too risky, given the miniscule probability that they will get funded. The new paradigm is for so-called Assistant Profs to get a grant while they are still in their mentor's lab, then start looking for jobs. Nothing sets the creative juices flowing like being set loose in your own lab with nothing but some good ideas, and that experience is being lost. But I'll admit, a big part of the problem is the large number of baby boomer scientists with $150,000 salaries, who could retire comfortably but just don't know when to quit, and keep getting funded mainly because of their political connections.

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