[lowem]

I read about this one earlier.

The good thing is that it is an "external combustion engine" (ECE?) - anything that can burn and give off heat can be made to run it. You could say it is almost as close as we can currently get to Doc Brown's "Mr Fusion" in the Back to the Future series.

The bad thing is that precisely *because* it is external, the heat transfer takes some time to take effect, i.e. to get converted into mechanical energy to "do work". It is unable to give the sudden, powerful acceleration that motorists hanker after which ICE's provide (due to the explosive internal combusion that takes place in ICE's).

[duff_beer_dragon]

Steamboy is out in cinemas soon,

see also The Difference Engine by Bruce Sterling and William Gibson.

Might as well entertain yourself, no point posting any info. here, I think it's just used to get the keywords so they can lock out any searches or webpages that mention them.

[Kingcoal]

A sterling engine is a Carnot heat engine, just like an ICE or steam engine. In both an ICE and steam engine, the exhaust carries the heat away. Heat engines make power from the differential in temperature. During intake/compression, the inferior of a gasolene engine is cold in comparison to the expanding exhaust gases that push the piston down during the power stroke. Those hot gases are wasted, literally out the exhaust pipe. That is still not enough to cool down an ICE, which is why the radiator and coolant is needed. A steam engine blows the hot steam and coal smoke out the chimney after which the cylinder(s) is cooled by a spray of cool water.

A Stirling engine needs to have the hot and cold differential maintained on ether side of it. The hot side must be fucking hot and the cold side must be fucking cold in order to get good efficiency. Otherwise, it has a hard time competing with a gas, diesel or even steam engine. The problem: the cold side can't move it's heat away fast enough when anything other than a token amount of power is needed.

Two applications that I know of are interesting. One is for sea faring vessels and uses the ocean to cool the cold side. The other is as an atomic battery replacement for space probes and uses outer space to cool the cold side.

[bentstrider]

Well, bugs like that could be worked out in due time.
I could really see it as a good power station piece.
Giving electric vehicles something to charge off of.
Still, alot better than facing the "bow-legged" side effects of riding a horse.

[rerere]

$this->bbcode_second_pass_quote('duff_beer_dragon', 'n')o point posting any info.

[rerere]

$this->bbcode_second_pass_quote('Kingcoal', '
')Two applications that I know of are interesting. One is for sea faring vessels and uses the ocean to cool the cold side. The other is as an atomic battery replacement for space probes and uses outer space to cool the cold side.

[backstop]

Bents - As I understand it the Stirling engine is a very serious bit of kit for particular niches in meeting energy demand.

It offers quite a high conversion efficiency with relatively low capital costs for burning fuels with low energy density (eg corn husks, wood chip etc) as well as available fossil fuels.

I've yet to see any discussion of it being used for city-scale power supply or any prototypes being developed for transport usage, but for village-scale stationary power it offers both CHP potential and the serious advantage of quiet running.

I'd be interested to see capital & operational cost data of comparable wood-chip fired Stirling and combined cycle gas turbine power plants. I note that the latter requires a considerably more compex and sophisticated manufacturing capacity, and may thus be less attractive for the global market.

The fact that operational data on a wood-fired Stirling is so scarce indicates only the inertia of the fossil fuelled status quo.

regards,

Backstop

[rerere]

$this->bbcode_second_pass_quote('backstop', '
')I'd be interested to see capital & operational cost data of comparable wood-chip fired Stirling and combined cycle gas turbine power plants.
The fact that operational data on a wood-fired Stirling is so scarce indicates only the inertia of the fossil fuelled status quo.

[backstop]

Rerere - It seems you're unaware both of worldwide development of wood gasification for use in various energy plant and of the major efforts in the EU and US in using woodchip furnaces to drive turbines for power.

Try a google on a few key words.

regards,

Backstop

[rerere]

$this->bbcode_second_pass_quote('backstop', 'R')erere - It seems you're unaware both of worldwide development of wood gasification

[backstop]

Rerere - I first wrote a paper covering the energy costs associated with the transport of wood in 1988, as part of a consultation to the UK government's Dept. of the Environment.

Your assumption that growing sustainable forestry for energy will thus lead to 'peak wood' is a nonsense. Any and every organic energy resource can be abused and degraded. The classic example is of US citizens being led to believe that it's a good idea to intensify the depletion of their prairie soils by buying Agribusiness Ethanol.

Intelligent Governments will set parameters for organic fuels' production that allow market competition while serving sustainability. More stupid ones are more likely to watch their people starve.

Wood is not, as you suggest, going to be the energy resource; it is already the feedstock for about 50% of the renewable energy used in Europe and looks set to provide a substantial share of future total demand for solid, gaseous and liquid fuels.

You need to make clear what 'waste stream' you're talking of as 'a fine development' before it makes any sense.

regards,

Backstop

[fastbike]

Whispergen are into distributed micro power stations. E.g. one in every house (under the stairs, in the basement or garage etc). Their inputs are NG (problematic in the long term) and the outputs are some of the household's electricity plus hot water.

[twxabfn]

http://www.eetimes.com/at/news/showArti ... 939&pgno=1

"By the end of 2005, they plan to have six dishes connected into a miniature power station capable of supplying enough 480-volt three-phase electricity to power about 40 homes (150 kW). The next step, in 2006, is a 40-dish power plant that will transform the combined output of the farm from 480 to 13,000 V, for distribution of industrial-level power to an existing substation. From 2007 to 2010, the program proposes mass-producing dishes to create a 20,000-dish farm supplying 230,000 V of long-haul power from its own substation directly connected to the grid.

If the project succeeds, the DOE predicts that by 2011, Stirling solar-dish farms could be delivering electricity to the grid at costs comparable to traditional electricity sources, thereby reducing the U.S. need for foreign sources of fossil fuels.

Eventually, according to DOE estimates, an 11-square-mile farm of Stirling solar dishes could generate as much electricity as the Hoover Dam, and a 100 x 100-mile farm could supply all the daytime needs for electricity in the United States. By storing the energy in hydrogen fuel cells during the day, Stirling solar-dish farms could supply U.S. electrical-energy needs at night too, as well as enough juice for future fuel-cell-powered automobiles, the DOE believes."

[Taskforce_Unity]

Sounds okay, relatively quick and easy to implement. The efficiency is not that good though, 16%. Still means downgrading a lot transport wise and luxury wise

[twxabfn]

$this->bbcode_second_pass_quote('Taskforce_Unity', 'T')he efficiency is not that good though, 16%.

[born2respawn]

$this->bbcode_second_pass_quote('Taskforce_Unity', 'S')ounds okay, relatively quick and easy to implement. The efficiency is not that good though, 16%. Still means downgrading a lot transport wise and luxury wise

[jpfrazer]

Anyone know about this technology?

http://www.lanl.gov/mst/engine/

Looks promising - especialy as it can be solar powered and the thermoacoustic bit has no moving parts.

[TrueKaiser]

if you think that works i have a bridge to sell you or some prime lake side real estate on titan.

[Kingcoal]

What's so good about it? We live in an age with 97% efficient natural gas condensing furnaces. Modern refrigerators are much more efficient than their ancestors.

What we desparately need is a replacement for the internal combustion engine for use in automobiles. Transportation accounts for something like 70% of oil consumption would wide.

[jpfrazer]

TrueKaiser
Areyou so sure it doesnt work? - looks like it does to me, but if you can point out where it breaks any laws of physics or can reference a source which criticises the technology I'd be interested. I'm not trying to sell it! I just wondered if among the many experts on the site someone had looked at it.

Kingcoal
I think the point is that it doesnt rely on fossil fuels - just temperature differences - and the efficiency quoted is far higher than photovoltaics. I agree we need transport solutions, as presumably in addition to the 70% of oil use you quoted, transport is responsible for a similar amount of CO2. 50% of CO2 comes from buildings and the construction industry - buildings dont need the efficiencies of lightweight oil, and can therefore utilise other energy solutions not appropriate for transport.

NG, even in efficient boilers, is on balance worse than oil in terms of CO2 because there are inevitable leaks and NG is a more powerful greenhouse gas than CO2.