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Comment Re:Cheaper drives (Score 2) 183

yes, but in smaller capacities, they will probably catch up before the end of the decade. At 320GB or so, a 250 GB SSD that costs $30 or $50 more will be a no brainer. I'm looking forward to the days when the cheapest laptops all come with SSDs because it's cheaper. It's kind of happening already with the 16 GB chromebooks, but a few more steps of moore's law will put that into very competitive capacities.

Comment Re:Nice Ad (Score 2) 62

Not to counter an ad with another, but has anyone here tried an emWave2, as blogged about here: It seems like it's the same thing the S5 is claiming, but as a separate device for $200. It'd be nice if phones could provide the same info for free/much cheaper. It looks like some HR bluetooth accessories can be paired with cheap apps to get a similar measurement. Any experience about their usefulness for stress management?

Submission + - Arizona Approves Grid-Connection Fees for Solar Rooftops ( 1

mdsolar writes: Arizona will permit the state’s largest utility to charge a monthly fee to customers who install photovoltaic panels on their roofs, in a closely watched hearing that drew about 1,000 protesters and may threaten the surging residential solar market.

The Arizona Corporation Commission, which regulates utilities in the state, agreed in a 3-to-2 vote at a meeting yesterday in Phoenix that Arizona Public Service Co. may collect about $4.90 a month from customers with solar systems.

Arizona Public is required to buy solar power from customers with rooftop panels, and the commission agreed with its argument that the policy unfairly shifts some of the utility’s costs to people without panels. Imposing a fee designed to address this issue may prompt power companies in other states to follow suit, and will discourage some people from installing new systems, according to the Sierra Club.

The “decision to add new charges to Arizona’s main rooftop solar program will stifle the growth of our clean-energy economy,” Will Greene, the organizing representative for the Sierra Club in Phoenix, said in a statement yesterday.

Comment Re:297 Suns? (Score 3, Informative) 165

Look at the graph at (about half way down). All the multijunction solar cells are run under concentration ranging up to ~1000 suns (1000:1 focusing of the suns energy). What's really impressive is that they are getting closer and closer to the 86% efficiency limit imposed by Carnot. Just like with Wind (~59% limit imposed by Betz's Law), our solar cells are approaching as good as we can get.

Comment Re:Treatment (Score 1) 111

I assume they are concentrating the contamination in order to have a smaller volume to store for 100+ years. Can anyone comment on: "In fact, I am writing this article while sitting on an airplane, and I am receiving more ionizing radiation from cosmic rays at this higher altitude than I would receive from drinking effluent water from the Advanced Liquid Waste Processing System. " Does this mean the 99.999% clean water from the treatment process would do no lasting damage over the rest of his life if he drank it? I feel like comparing external radiation to internal (and potentially more concentrated by bodily functions) is nice and calming, but over what time scales is the author's statement valid? Drink nothing but the permeate for the rest of your life and be no worse off than one intercontinental flight?

Comment Re:Depends on the price of gas (Score 1) 359

There are two big things that can help electric cars (does Musk also include plugin hybrids?) 1) like you said, is the cost of gas. It's not going to stay at $3.50 or $4 a gallon, in 20 years, we may well have hit oil's terminal decline phase, and even if not, the cheap stuff is gone. Expect at least $10/gallon in current dollars in 20 years. 2) the cost of batteries. They're going down. Fast. see: I actually used the 8% growth in energy density claimed above, which brings my price to $220/kWh in 2025 (not $160 like mckinsey claims). At that price, a 100 mile range battery will cost $8000, down from about $20,000 today. By 2032, prices could come down to $4500 for a 100 mile range. This assumes exponential gains in capacity/density/etc, but those gains have happened in the last ~15 years. The big question is whether they'll continue in the future. I'd say we'll get to about $250/kWh before battery scientists slow down, but improvements won't stop. That will get us to some pretty cheap, reasonable range electric cars in 20 years. Basically, the Nissan Leaf will go from $35,000 ($20k for the car, $15k for the battery) to $25,000 ($20k for the car, $5k for the battery) [assumptions: no EV efficiency gains, still 35 kWh/100miles, which is what the Leaf, Volt, and plug in Prius achieve today.]

Comment Re:Nuclear Would Use Less Land with Higher Output (Score 1) 572

The next 1 gigawatt nuclear plant built in the west will cost 5-10 Billion dollars. Look at Finland's effort: three years or more behind schedule and easily 50% over budget. The economics and short work schedules are what make renewables more attractive than these hulking plants designed with the 1960s mindset. Smaller plants have much lower impact if they go down, and can usually get back online faster than a large coal plant (1 day) or a nuke (1-4 weeks). I used to like nukes, being a technocrat, but the economics don't work out. They actually never worked out. Over the history of the grid, total capital expenditures have been roughly equally divided between generation (power plants), transmission (high voltage, long distance lines) and distribution (the lower voltage lines on wood poles bespoiling your suburb). In fact, transmission was 10-20% more than the other two, which tells you the problem with giant wind farms in the Dakotas. The exception to this was the 1970s, when our current fleet of nukes was built, and generation took up almost 50% of that CapEx pie. So be happy that your utilities are encouraging everyone to save energy rather than build new plants, because we need end use efficiency to get us more cold beers and hot showers for less energy, before we need more power plants, nukes included.

Submission + - Cap and Dividend to fight global warming (

qval writes: In an older article, Scientific American discusses the benefits of an alternative to the Cap and Trade system John McCain and Barack Obama agreed about during the recent election. Instead of giving away credits, as Europe did, or auctioning off carbon allowance credits and pocketing the revenue, a dividend is paid to stakeholders, i.e. all of us. The dividend is equal for all, so poorer low-carbon users would benefit while carbon spewers shoulder more of the cost.

Comment Re:Reasonable idea (Score 1) 503

What do you mean by taxing generally? Huckabee's huge sales tax? How about controlling externalities. I see the slippery slope of taxing sin, but isn't every tax bad and discouraging, so we might as well raise revenue in this way. Governments around the world are proposing bans on incandescent bulbs in the next 5 years. A tax is a cleaner, revenue-raising alternative. Think Amory Lovins' feebates if they have to be revenue neutral.

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