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http://www.stirlingengine.com/
Build your own: http://www.lindsaybks.com/

I can't vouch for it yet, but what I'm buying myself for the holidays is
model stirling engine;
http://www.stirlingengine.com/ecommerce/product.tcl?product_id=87
It's 49$ (3 for 100$) not including the coffee mug or ice. The better model will run on hand heat.

A runnerup choice was the ultimate dreidel or top that will spin for
http://www.quirkle.com/top/index.htm

The first is localized ground/surface water pollution. The water pulled from deep geothermal springs has many chemicals dissolved in it that are not normally found in high concentrations in surface waters

Fossil water isn't needed. Actually water may not be the best carrier of heat to use, but if used water doesn't need to be pumped up. A closed loop can pump surface water down where it is heated up then it comes back up where a heat pump then extracts the heat.

Extra heat must be dispelled from some point in the power plant to maintain a thermal gradient. Efficiency requires a high level of heat transfer, so the excess heat will have to be dumped into the environment.

What extra heat? Where you see "waste heat", I see another energy source. And efficiency requires more of that heat energy to be extracted. If the water is hot it still has plenty of energy that can be used.

If direct ejection into freshwater systems is not feasible, then the water will have to be cooled in a cooling tower,

In a closed loop the cooled water is just pumped back down where it picks up more heat before coming back up. If the water still has heat before being pumped back down then 1, more energy can be extracted or 2, it won't need to heat up as much but this isn't as efficient as the first option. Also where it's cold cogeneration can be used. The heated water can be used to heat building as is done in Iceland. Oh, I see you mention it later. Another place that use cogeneration systems like this is NYC.

Doc,

Looking around I have found a couple of possibilities. I think that heat engines might not be the best way, given that (in my head) the stored hot water cannot be recycled into the system very efficiently. I'm probably wrong about that. Anyways, from what I've read, the underlying heat engine is very efficient, it just has a limited range of applications (submarines!). I'm also intrigued by this Quasiturbine engine. It is said it can be configured as a steam engine: Store superheated water in a nice insulated place and use it to drive your electrical system. Perhaps the way to go?

http://auto.howstuffworks.com/quasiturbine.htm
http://en.wikipedia.org/wiki/Quasiturbine
http://www.howstuffworks.com/stirling-engine.htm
http://en.wikipedia.org/wiki/Stirling_engine
http://en.wikipedia.org/wiki/Carnot_heat_engine
http://www.stirlingengine.com/

Sterling engines are "heat differential" engines. They require a hot-side, and a cold-side. It doesn't matter where the "hot" and "cold" come from. A cup of coffee or your hand (relative to ambient air temperature) works great for small Sterling engines. The solar focusing technique is just one implementation.

There is a lot of research that goes on you just never hear about it. How about http://www.stirlingengine.com/ or http://www.nanosolar.com/ ?? Those companies founders are risking it all, and if they fail, you'll never hear about it.

but hasn't it always been that way? Er, well - maybe it used to be that way. Today we have ginormous established companies that use all the tools available (primarly lobyists/governments) to suppress competitors that make them obsolete.

thanks for the links, btw.

There is a lot of research that goes on you just never hear about it. How about http://www.stirlingengine.com/ or http://www.nanosolar.com/ ?? Those companies founders are risking it all, and if they fail, you'll never hear about it.

The rest of the equipment: heat collector at the focus, flexible piping, insulation, pipes, evaporators, heat sinks, pumps, working fluid, turbines, gears, cogs, lubricants, generators, buildings, staff, land

What do you need all that stuff for?

With the exception of land (which you will need a lot of but it's all desert and not suited for much else) and a minimal staff, none of that junk is required.

The Stirling cycle runs at 10% efficiency. { Note: most Stirling engines are about 5x less efficient that this}.

This is a little ambiguous. The theoretical Stirling engine can achieve the ideal Carnot efficiency. Real Stirlings can reach 50 percent of this maximum theoretical value.

With a ambient (sink) temperature of, say, 110F (316K) and a temperature of 1400F (1033K - Actually a conservative estimate) our Carnot efficiency is 69.4%. A real high-end Stirling can reach 50% of that, or nearly 35% thermal. After you generate the electricity you are *still* looking at 25% overall efficiency or better.

All that stuff cleans and maintains itself at no cost.

Practically would! If a crew of 3 guys can take a hose truck and rinse the dust off the mirrors of each dish in ~15min, they can do about 30 dishes per day. Each dish would probably only need to be washed once a month, so 30*30 = 900 dishes a month. You'd need 23 crews of 3 men each to maintain 20,000 dishes, or 67 people. A 500MW coal plant would employ about 100. (Guestimated from here) Moreover, the people running a coal plant would have to be skilled to maintain the high pressure steam equipment, which means they would cost more. You would not need special training and licensing to operate a hose truck.

As for the Stirling gen sets themselves, they are hermetically sealed and virtually maintenance free. You can contract out any service that might be required rather than having your own staff. In fact, I would think SES would offer a nice warranty that includes service, so if one does go down simply replace it with a spare unit (They are small and modular, you know) and send them back for service.

The tracking systems are also fairly low maintenance and could be contracted out.

So in light of the above, you may wish to revisit your calculations.

They make a breakthrough and develop an efficient Stiring regenerator, which is simultaneously long and short, conductive and insulating. See : www.tinaja.com/glib/muse116.pdf

So you based your argument on three sentences (one copied almost verbatim) from a journal that seems to deal mostly with electronics? Brilliant. You, sir, seem woefully uninformed about how Stirling engines operate. I will grant you that the regenerator is perhaps the biggest hang up when it comes to design, but by no means is it impossible to create. What you are tying to do is make a medium that stores and rejects heat quickly ("highly conductive") with minimal internal volume ("long and thin") and low pressure loss for gas flow ("short and fat") and does not create a thermal short ("highly insulating"). In practice, a stack of fine mesh stainless steel screens works quite well. I have also read storied about people stuffing the passages in the engine with brass wool to great effect.
=Smidge=

It's great to see a huge energy implementation using that principle.

Sterling is a currency, or a grade of silver.

The larger the temperature gradient the higher the efficiency of the engine. But then, if you are getting the temperature gradient essentially for free, the efficiency isn't your most important consideration. There are Stirling engines which will run on the temperature gradient between the palm of your hand and ambient air.

e.g.
http://www.stirlingengine.com/

Powergen (a UK power company) are rolling out Stirling engines across the country. Replacing conventional central heating boilers with a product they call Whispergen, a Stirling engine.

e.g.
http://www.powergen.co.uk/pub/Dom/A/ui/Residential /TechnologyAndInitiative.aspx?id=30

I can't comment on the inability of others to build a reliable engine.

from which one can extract energy, but of course some processes are more efficient than others, and I'm not that familiar with the technologies and how efficient they are, but the name Stirling engine comes to mind as a possibility. This prompted me to actually READ TFA, and incredibly, Stirling engine is not mentioned. Here's a FAQ:
http://www.stirlingengine.com/faq/one?scope=public &faq_id=1

am desperatley waiting for the fusion revolution in +/- 50 years tho, i drool at the thought of unlimited energy. It will happen...

And within ten years of "unlimited" energy everyone* will have the electric-power equivalent of SUV's to go to soccer practice and the supermarket. If it's literally freem poower use will expand to meet the the generation (and distribution! We'll need fatter wires) capability.

*For pedants, this word is used idiomatically, not literally. Thank you for your understanding.

Wasn't Dean Kamen working on this?

Why yes, he was.

I hope he is working on this solar project (or one like it). He could certainly sort out the remaining issues.

Fair enough. But what about a micro-stirling engines (as I suggested earlier)? They're already being used in waste heat recovery, and are far more effective in the lower power ranges. In that case the heat *is* useful.

Great. Just what I want. Greater dependence on big oil companies. It isn't enough that they're screwing me on fuel prices for my car, now they want to have a cut in providing power for my laptop and/or cell phone, too. This technology is not the answer. It's the question. "HELL NO" is the answer.

True 'dat.

And the australian Collins-type submarines were built by Kockums Marine Systems in Sweden; those Stirling AIP engines are quiet as well as being able to allow the submarine to stay submerged several weeks. Interesting that Sweden possess such a prominent position in the submarine market (scroll down towards the end).

Okay I'm interested in seeing this jet-fuel stirling engine. How well does it work in extreme cold?

For those of you who may not know much about stirling engines, here's some information.

But did anyone notice what was missing? Did you see in the flash animation on the chart of refrigerants that the one refrigerant that isn't EPA approved is also (supposedly) the safest - ie, HC's? Now, I know the presentation wasn't about HC's - but why did they list them, but not talk about them - and why don't they have EPA approval if they are *better* than CFCs and HFCs?

There are other cooling technologies out there that are "environmentally friendly" - one such technology is used almost exclusively for cryo-cooling (you know, cooling to cryo temperatures - much colder than freezing), and could be used for regular cooling: the Stirling Cycle.

We have all heard of Sterling Cycle engines (or at least, I hope we have!), which are "external combustion" engines that utilize thermal energy transfer from hot to cold to create mechanical motion (all it needs is hot and cold - some small demo models can run on an ice cube and/or hot coffee - or the heat from a monitor!), which then can be used to do work.

Well, if you reverse that, and instead put mechanical motion in, the hot side get *very* hot, and the cold side gets *very* cold (in an efficient Stirling Cycle engine).

There is a company out there that makes such Stirling Cycle heat pumps (which can also be used as an engine - they sell kits to experimentors) that use a solenoid-type electromagnetic driver system (run in reverse, the solenoid generates electricity!) - unfortunately I can't find the link to them, but they make cryo-coolers using the Stirling Cycle and electromagnetic drivers.

More information and kits for Stirling Cycle engines can be found here.

Also note that google can help you find a lot of links on the subject, too.

Stirling Cycle engines aren't the only environmentally friendly way to cool things - there are methods that use the power of the sun! One could run a refrigerator off of solar panels (not very efficient). A better method uses something called something like "ammonia sodium absorption" - which basically uses heat to expand ammonia in a closed system (similar to a propane refrigerator). Now, ammonia is a nasty substance (poisonous) if it gets out of the system, but it isn't the only method.

One could take two Stirling Engines, hook the shafts together, have one be driven by a solar concentrator, the other would act as the heat pump - this is likely to be more efficient than a solar electric version.

I have also heard of an innovative way of using wind power to cool something down (and heat something up - why "waste" the hot side?) - run an AC compressor directly from the blades (instead of a generator) and store the cold and heat in separate insulated water storage tanks, for use later to cool/heat the house or such.

Another method, while "solar" doesn't directly use the sun, but is similar to how the earth heats and cools - negative radiant energy. In fact, you can use a solar oven to make ice using this method - but I will describe a simpler manner: Get an old large freezer (doesn't need to work - we need an insulated box) - put a ton of extra insulation around it. Paint the inside black. Put about a half inch of water in the bottom. When the sun has set, open the lid wide open to the sky. Before the sun has risen the next morning, close the lid. Do this several times, and eventually the water in the bottom will freeze (note, this will likely not work during the summer months in hot climates, unless you can insulate the box extremely well during the day). By openning the box to the night sky (adding reflectors will help, just like on a solar cooker, to allow it to "see" more sky), the heat is let out, cooling the inside. Closing it in the morning "traps" the coolness inside, waiting for the next cycl

They get cold as hell, are much cheaper, more effecient, much quieter, much safer, less moving thingys to go boink.

http://www.stirlingengine.com/

Here ya go....http://www.stirlingengine.com/

How about Sterling Engines??
http://www.stirlingengine.com/

I've always been fascinated by these.
I want to rig one at the focal point of a BUD satellite dish (coated with mirrors) to generate free energy while tracking the sun.

Put a temprature differential on the two cylinders and you get power output.
Put power to the crankshaft and get hot and cold output.
Here's a clip from the Stirling site,
"It's not obvious but a Stirling engine is a reversible device. If you heat one end and cool the other, you get mechanical work out, but if you put mechanical work in, by connecting an electric motor, one end will get hot and the other end will get cold. If you design the machine correctly, the cold end will get extremely cold. In fact, Stirling coolers have been made that will cool below 10 degrees Kelvin. Micro Stirling coolers have been produced in large numbers for cooling infrared chips down to 80 degrees Kelvin for use in night vision devices."

I think it would be neat as hell to incorporate one into a PC somehow and recover some otherwise lost BTU's...

Just glancing over it this looks like a take off of the Sterling engine.
I saw mention of heating air and cooling air and other "Sterling like" things..
I'll read it in full detail over coffee later but it looks really neat. Good link...

heh, that picture of a bowel of water on top of an open pc tower case is not something I would necessarily run, but I would imagine that you could make the system safer by enclosing the bowel and lines and perhaps passing the lines in through an empty PCI slot bay..

Still I would imagine you might need more space to accomplish this sort of solution. Has anyone looked into stirling engines as a method of heat transferal? They have no moving parts and are reportedly fairly effecient. I have been looking into using them to harness solar power.

Look at openACS. Its a fast evolving toolkit, with a lot of features out of the box. The current project website is not the best looking, but the toolkit has been used to develop a lot of interesting sites.

Methodology
If I were you, I would stay away from the Vignettes and other off-the-shelf CMSs. To paraphrase Phil Greenspun, these guys pricing works along the lines of ... shake the customer by his feet and see how much money falls out, then charge another $50 000k for support.

I would also not be in a rush to implement a totally custom solution. Building from scratch is usually a dumb idea(tm). No point in reinventing the wheel. Having said that there is a slight difference between a Michelin-clad Ferrari wheel and a 0BC Roman chariot's wheel...

I agree with you, do not go for the slashdot look. That virtually rules out most of the nukes (phpnuke, postnuke, drupal, slashcode etc). It is

so boring

so overused

suitable for weblogs and news sites but not for more mainstream content sites.

oss is good
The beauty of using OSS toolkits is that you get a head start. If any consultant (read salesman) tells you that their product fits your needs perfectly, then a. shoot them, b. chop them into little pieces c.feed them to the snakes d. shoot the snake ..... just for good measure.

The best that you can hope for is to have a basic and solid foundation that you can build on.

decisions
Some of the things to look for include the following:

• ability to handle workflow.
• ability to deal with permissions
• ability to deal with authentication
• ability to handle more than just plain text
• ability to version ... rollbacks ... track changes
• ability to handle templates, ... proper templates, not just color changes.
• level of developer support
• level of developer competence
• pace of changes

For each toolkit, look at sites that have implemented it. If they *all* look the same, steer clear. Its a sure sign that templating was poorly implemented, or that the toolkit is difficult to customise.

Post a couple of questions on the boards. If the tone is friendly, then you know that if you did pay these guys to do work for you, the service would be great.

If you are building a proper CMS, its going to be painful.

and you win an all expenses paid tour of some of the sites built using openACS and its cousin ACS classic.

• Grand Expeditions
• Wine Access
• photo.net
• Stirling Engines
• Online Ireland and more here
• Away
• Sherman power sports
• Net effect