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Comment Re:Misleading and false (Score 1) 127

The easiest way to get up around 32% efficiency is to stop using semiconductors and use concentrated sunlight to drive a turbine instead. Glass mirrors are fairly cheap per square meter.

Solar concentrators don't work for residential solar, because of the need to track the Sun. But utility-scale solar panel farms beat residential by 2.5x on cost anyway. The panels cost the same in both cases, but all the other costs are much lower for a solar farm when you install them at ground level by the hundred thousand, than on a home rooftop by the dozen. Rooftop solar is nice to have, but not really cost-effective.

Comment Re:age 30 is old and $60K is "wealthy" (Score 1) 153

> And having a penny would make me the richest person on Mars.

Then the Curiosity rover already took the top spot, because they included a Lincoln penny in the camera reference target. Why a penny? It doesn't weigh much, copper isn't expected to degrade in the Mars environment, and they know what it looks like. There are also color patches and grids of black and white lines. The point of the reference target is to calibrate the cameras with known objects, so they can tell the actual colors of the Mars environment, despite lighting changes as the Sun moves, and the occasional dust storm and cloud.

Comment Re:But, but, we have alternative facts! (Score 1) 366

No, turnout was down because Trump's core supporters are poor rural voters who can't afford a D.C. hotel or even find it on a map. The women's march the next day, on the other hand, had more liberal voters, who earn more money on average and are better educated, and the march had better entertainment. So they had twice the turnout.

Comment Re:Good idea (Score 1) 366

> Since when did Bill Gates and Warren Buffet turn into Climatologists?

Well, Buffet's company owns MidAmerican Energy ( https://en.wikipedia.org/wiki/... ) which owns multiple gigawatts worth of wind turbines. One of their customers is Microsoft. They may not *be* climatologiests, but they certainly are smart people, and can easily afford being *briefed* by climatologists as part of their business decision making.

Comment Re:That is *terrible* news (Score 1) 364

Solar panels do degrade over time, because by their nature they are constantly exposed to the Sun. The UV component degrades the electronic junctions over time, but it's in the range of 0.5-0.7%/year output decrease. The other parts of the panel (cover glass, aluminum frame, wiring) also suffer the usual effects of outdoor exposure.

So you can expect over a 30-50 year period it will make sense to replace old panels with new ones, and recycle the old ones. The average age of installed panels in the US is only 3 years, because the installation rate has been rapidly growing. So it will be a while before the replacement business will be significant.

Comment Re:That is *terrible* news (Score 1) 364

> In 30+ years it still hasn't taken off, primarily due to cost.

Solar really took off in 2008. Before that, the quantities of silicon needed for solar cells was smaller than that needed for electronics. So it wasn't cost effective to build plants to make "solar grade" silicon. They just piggybacked on existing "electronics grade" production. Electronics needs very few defects in the silicon, because one defect can render a chip non-functional. A defect in a solar cell just lowers the efficiency a tiny bit. Solar-grade silicon costs 20x less per wafer. Once they started mass production of it, the cost of cells dropped like a rock, and production expanded by 75x from 2008 to this year, and still climbing.

> I will be installing solar panels soon,

Rooftop solar currently costs 3x as much as utility-scale solar, for the amount of power it produces. The panels themselves are the same, but the labor for installing a dozen panels on a roof is way higher than installing 300,000 on the ground in a solar farm. The solar farm gets them wholesale from the manufacturer, he only has to get one permit and make one power line connection instead of thousands, etc. If the numbers work for you, great, but you might get a better deal investing in a "yield co", a company that invests in solar farms for the income yield, and using that income to offset your electric bill. A new alternative is "community solar". That's where the utility builds a solar farm (like mine just did), and lets you buy the panels or the power they produce, and it gets deducted from your bill. That works for people like me. I have nice big shade trees around my house I don't want to cut down. It even works for renters, who can't put things on the roof. Just check out all the options before before you jump.

Comment Re:Full employment for .... (Score 1) 364

Robots already do the cleaning on solar farms. The panels are installed on long rows of support structure, and the cleaning bot runs on tracks along the top and bottom. It doesn't even need batteries, because, you know, solar panels. It just taps off a little of the power the row is producing. For the desert solar farms in the south-west, it's actually fairly necessary to clean them periodically, due to dust build-up. In rainier climates it's needed a lot less.

Comment Re:Alternate Headline (Score 1) 364

Building a power plant is labor intensive. Running it, not so much. So about 5000 people are working on building the Vogtle 3 & 4 nuclear reactors, on the GA/SC border. Once the new reactors are finished, there may only be 100 new jobs in running the two new reactors.

Same goes for a solar or wind farm today, or a hydroelectric dam in the mid-20th century. Lots of work to build it, not that many to run it.

Comment Re:Employment is not the goal (Score 1) 364

> there's a good chance that we've reached peak jobs and the number of people who need to work to provide for all goods and services will start to shrink.

I've spent the last several years working on the concept of Seed Factories ( http://en.wikibooks.org/wiki/S... ). These are starter sets of core machines (lathe, solar furnace, modular robot, etc.), which are used to make parts for *more* machines, until you have a mature factory. This is similar to the way a biological seed grows into a mature tree. The mature factory then produces things people want and need. The growth and operation of the factory is mostly automated, working from stored design files.

The starter set is less expensive to buy than a full factory, and being mostly automated, less expensive to run. Groups of people can split the cost of the starter set, and tend to the growing factory part-time, in addition to regular jobs. As the factory grows, it can produce more products, and the owner/operators can work conventional jobs less. There will still be personal service type things, and some people will work because they enjoy the work, but basic stuff like food, housing, and utilities can all be automated away to a large degree.

I'm convinced this sort of transition is not just possible, but inevitable, because it has better economics than the old way of doing things, and better security. A regular factory will lay you off to save a buck. That doesn't happen if you are part owner. It could go 100% automated, and you still get the stuff you need. During the transition period, it gives people a fall back position if they lose their main job. They just go work at "their factory" instead, while looking for another paid job.

Comment Re:Who's the jobs creator? (Score 4, Informative) 364

> He campaigned on bringing back coal-producing jobs. ... The cost of coal compared to other energy-sources, combined with automation, may prevent him from doing so.

Let's put it this way. The Southern Company (big southeast utility company), just finished their first big "clean coal" plant in Mississippi. It's clean in the sense of having the latest scrubbing tech, and the CO2 it produces will be sent down a pipeline to be injected into Gulf Coast oil wells to pump out more oil, and sequester the CO2 underground. It cost *ten times* as much per kW of capacity as utility-scale solar farms in 2016, and solar farms don't need fuel to keep running.

That's why Georgia Power, one of the Southern Co's divisions, is building 2.5 GW of solar in the next few years ( http://www.prnewswire.com/news... ). The Utility's divisions (Georgia Power, Alabama Power, etc.) are divided that way because each state regulates them differently. They are also half-owner of the Vogtle nuclear plant on the GA/SC border, which is adding two new reactors with 2.2 GW capacity.

Coal is dying. Ten years ago it supplied half of the US's electricity. Now it's down to 30%. It's mainly being replaced by Natural Gas, wind, and solar. It just takes a while to replace half the nation's electric capacity. Trump got votes by telling coal-country voters he's bring back jobs, but it ain't happening. According to the Energy Department, ~15 GW of renewable power plants are scheduled to be added in 2017, and 4.7 GW of coal plants shut down. That just continues the trend of the last decade.

Comment Re: Stop it. (Score 1) 333

He also lied about turning over his businesses to his sons. According to state offices which oversee corporations, he hasn't turned in the paperwork yet. The pile of file folders he used as a prop in his news conference about that subject were full of *blank paper*, as shown by a media photograph.

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