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My in-laws house is coal-heated. They have an actual coal burning furnace and just huck a few chunks in every so often. So crazy.
The house that I grew up in was built with a coal fired furnace. There was a chute out front and a huge coal hopper in the basement that to this day probably has more than a ton of coal left in it. I was told that there was a huge screw drive mechanism that fed the coal to the furnace, but it was long gone by the time I was born.

The coal would show up in our stockings when we were kids.

 
Just finished reading Earth: The Sequel

http://www.amazon.com/Earth-Sequel-Reinvent-Energy-Warming/dp/B005FOF96Q/ref=sr_1_cc_1?s=aps&ie=UTF8&qid=1330009136&sr=1-1-catcorr

Pretty interesting book. The edition I read was published in 2008, and was surprising frank about the shortfalls of the technology at the time. It was, history shows, woefully optimistic about the shortfalls being overcome in a few short years. There were some interesting ideas for harvesting wind from the jet stream that I'd never seen before.

Also, a lot of the 'green' companies in this book have disappeared in the years since publication.

 
we have some farmers down here installing single turbines and solar panels to power their farms. one did it about year ago with a small turbine and solar panel set up...they apparently haven't had a power bill since they put them in...they have been able to generate enough. The other which is right down the st from us but in a slightly larger turbine about a month ago...so it is too soon to tell.

 
Interesting article about solar in SC.

http://www.thestate....ml#.UHv-nG_R4TY

I don't think the writers grasp the difference between solar generation for the grid and solar cells on houses.

I KNOW they don't understand the ramifications for the different ways to configure the system.

To the EE guys: Is there really that much of a technical issue with your home system feeding back to the grid? The local electric companies make a huge deal about it (moreso than this article reflects).

 
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To the EE guys: Is there really that much of a technical issue with your home system feeding back to the grid? The local electric companies make a huge deal about it (moreso than this article reflects).
Yes. Electric distribution systems (i.e. from the substation to the house) are designed for power to flow in one direction. Once you start connecting sources that can back feed it causes all sorts of problems. It can cause protective devices (fuses and reclosers) no longer to coordinate so either you trip off a lot more customers than required for a fault--or worse, don't trip at all and the line burns down. If the amount of generation is large enough it can island with the load--that is, the customer's generation backfeeds other customers at a time when the utility end has tripped off. This will often result in bad voltage and frequency, which will damage electrical equipment. And of course, there's the risk of backfeeding into a downed wire, which could cause injury or death. There's probably other issues as well, but these are the ones that jump to my mind.

The IEEE standard 1547 is supposed to address these issues. As long as each generator interconnection is compliant, these shouldn't be a major problem. However a lot of these people are nut jobs who think they shouldn't have to comply and the big bad utility is simply out to get them... which results in them putting everyone's safety in jeopardy.

 
To the EE guys: Is there really that much of a technical issue with your home system feeding back to the grid? The local electric companies make a huge deal about it (moreso than this article reflects).
Yes. Electric distribution systems (i.e. from the substation to the house) are designed for power to flow in one direction. Once you start connecting sources that can back feed it causes all sorts of problems. It can cause protective devices (fuses and reclosers) no longer to coordinate so either you trip off a lot more customers than required for a fault--or worse, don't trip at all and the line burns down. If the amount of generation is large enough it can island with the load--that is, the customer's generation backfeeds other customers at a time when the utility end has tripped off. This will often result in bad voltage and frequency, which will damage electrical equipment. And of course, there's the risk of backfeeding into a downed wire, which could cause injury or death. There's probably other issues as well, but these are the ones that jump to my mind.

The IEEE standard 1547 is supposed to address these issues. As long as each generator interconnection is compliant, these shouldn't be a major problem. However a lot of these people are nut jobs who think they shouldn't have to comply and the big bad utility is simply out to get them... which results in them putting everyone's safety in jeopardy.
Thanks for the info. Makes sense.

If the system was designed not to feed back to the utilities, this shouldn't be an issue, though, right? I'm thinking of systems that feed off the PVs primarily and suck utility power when excess is needed (most of the time).

 
No, actually it makes very little difference how big the customer's load is in comparison to the amount of generation (within reason--if the customer is installing a huge amount of generation there are other concerns to deal with). The problem is in the case of a short circuit on the utility side, the electricity will backfeed the short regardless of how big the load is.

 
So the only way to get around that is go completely off grid or install an offgrid electrical subsystem (which logcally doesn't make much sense).

Dad had to jump through similar hoops when he rigged their house to switch between his generator and the grid.

 
Yeah, a big driver behind that is safety. At the voltages we're talking about (anywhere from 5,000 to 35,000 volts) it only takes tens of milliamps to hurt/paralyze/potentially kill someone. Nothing against your dad personally, but if I were a line worker I wouldn't want to trust my life to every Tom, **** and Harry with a generator out back.

 
No, I hear you.

The electricity company basically put a "check generator switch before work" notation on his line after blessing it. He has one of those big dudes that runs off his tractor PTO.

 
Suntech Power Holdings Co. Ltd. (STP) became the first company from mainland China to default on its bonds after failing to repay $541 million of notes due March 15, breaching terms of other outstanding loans.

The move pushes what was once the world’s biggest solar panel maker into default on credit lines it has with International Finance Corp. and Chinese domestic lenders, Suntech said today in a statement from its headquarters in Wuxi. China Development Bank Corp (SDBZ). has loans to Suntech.


http://www.bloomberg.com/news/2013-03-18/suntech-says-it-received-notice-of-default-on-bonds-due.html

So, it appears not even the Chinese could make a go of solar cell production...even with all the EU and US incentives, low Chinese wages (which aren't so low anymore), and lax pollution regs.

 
Germany once prided itself on being the “photovoltaic world champion”, doling out generous subsidies—totaling more than $130 billion, according to research from Germany’s Ruhr University—to citizens to invest in solar energy. But now the German government is vowing to cut the subsidies sooner than planned and to phase out support over the next five years. What went wrong?
Subsidizing green technology is affordable only if it is done in tiny, tokenistic amounts. Using the government’s generous subsidies, Germans installed 7.5 gigawatts of photovoltaic capacity last year, more than double what the government had deemed “acceptable.” It is estimated that this increase alone will lead to a $260 hike in the average consumer’s annual power bill.

According to Der Spiegel, even members of Chancellor Angela Merkel’s staff are now describing the policy as a massive money pit. Philipp Rösler, Germany’s minister of economics and technology, has called the spiraling solar subsidies a “threat to the economy.”


Germany’s enthusiasm for solar power is understandable. We could satisfy all of the world’s energy needs for an entire year if we could capture just one hour of the sun’s energy. Even with the inefficiency of current PV technology, we could meet the entire globe’s energy demand with solar panels by covering 250,000 square kilometers (155,342 square miles), about 2.6 percent of the Sahara Desert.
Unfortunately, Germany—like most of the world—is not as sunny as the Sahara. And, while sunlight is free, panels and installation are not. Solar power is at least four times more costly than energy produced by fossil fuels. It also has the distinct disadvantage of not working at night, when much electricity is consumed.
In the words of the German Association of Physicists, “solar energy cannot replace any additional power plants.” On short, overcast winter days, Germany’s 1.1 million solar-power systems can generate no electricity at all. The country is then forced to import considerable amounts of electricity from nuclear power plants in France and the Czech Republic.
Indeed, despite the massive investment, solar power accounts for only about 0.3 percent of Germany’s total energy. This is one of the key reasons why Germans now pay the second-highest price for electricity in the developed world (exceeded only by Denmark, which aims to be the “world wind-energy champion”). Germans pay three times more than their American counterparts.
Moreover, this sizeable investment does remarkably little to counter global warming. Even with unrealistically generous assumptions, the unimpressive net effect is that solar power reduces Germany’s CO2 emissions by roughly 8 million metric tons—or about 1 percent – for the next 20 years. To put it another way: By the end of the century, Germany’s $130 billion solar panel subsidies will have postponed temperature increases by 23 hours.
Using solar, Germany is paying about $1,000 per ton of CO2 reduced. The current CO2price in Europe is $8. Germany could have cut 131 times as much CO2 for the same price. Instead, the Germans are wasting more than 99 cents of every euro that they plow into solar panels.
It gets worse: Because Germany is part of the European Union Emissions Trading System, the actual effect of extra solar panels in Germany leads to no CO2 reductions, because total emissions are already capped. Instead, the Germans simply allow other parts of the EU to emit more CO2. Germany’s solar panels have only made it cheaper for Portugal or Greece to use coal.
Defenders of Germany’s solar subsidies also claim that they have helped to create “green jobs.” But each job created by green-energy policies costs an average of $175,000—considerably more than job creation elsewhere in the economy, such as infrastructure or health care. And many “green jobs” are being exported to China, meaning that Europeans subsidize Chinese jobs, with no CO2 reductions.
Germany’s experiment with subsidizing inefficient solar technology has failed. What governments should do instead is to focus first on increasing research and development to make green-energy technology cheaper and more competitive. Production should be ramped up later.
In the meantime, Germans have paid about $130 billion for a climate-change policy that has no impact on global warming. They have subsidized Chinese jobs and other European countries’ reliance on dirty energy sources. And they have needlessly burdened their economy. As even many German officials would probably attest, governments elsewhere cannot afford to repeat the same mistake.


http://www.slate.com/articles/news_and_politics/project_syndicate/2012/02/why_germany_is_phasing_out_its_solar_power_subsidies_.html

 
Holy carp! Look at the subsidies per megawatt-hr!

ED-AP639_1energ_NS_20120817170303.jpg


http://online.wsj.com/article/SB10001424053111903285704576559103573673300.html

 
Why are subsidies being paid at all to oil, gas, or coal power plants when an attempt is being made by the government to shut them down? Also, in most areas, power companies are allowed to charge customers for whatever the power costs to produce, plus any past or future upgrades to equipment, plus a set percentage of profit. They are regulated monopolies that cannot fail to turn a profit by law. Why in the hell do they need federal subsidies in the first place?

 
They do turn a profit, but that profit is legilated.

Honestly, I didn't think solar was that high.

 
Wind Turbine Syndrome' Blamed for Mysterious Symptoms






"I didn't put anything to the turbines -- we heard it and didn't like the thump, thump, thump and didn't like seeing them, but we didn't put it together," she told ABCNews.com.


Yeah..I think you put it together just fine.

Don't like something? Develop an ailment and blame it on something you don't like.

http://abcnews.go.com/Health/wind-turbine-syndrome-blamed-mysterious-symptoms-cape-cod/story?id=20591168

 

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