Stirling Machine + Solar Power?

[Pii 0]

I don't know have anyone made the system yet. But, if there wasn't I figured that it would be interesting to investigate. Stirling uses difference of temeperature from two surface and turn it into motion which can be use to drive a generator creating electricity.

 

The solar power is plenty and but the reason why we cannot simply rely on them is because of the cost of photovoltaic cells.

 

But what if we can just use array of mirrors to focus light into an one side of stirling machine enclosed in a transparent glass (to induce greenhouse effect). Would that give us a comparetively lower cost to energy ratio comparing to the conventional photovoltaic cells?

 

This configuration can be applied to developing countries as it doesn't involve in complicate configuration and manufacture of sensitive equipments.

 

This topic is inspired by http://forums.xisto.com/topic/97125-topic/?findpost=1064402253 topic

 

More info on Stirling Engine

https://en.wikipedia.org/wiki/Stirling_engine

[wutske 0]

Wouldn't be very effective as you'll have to make sure that the other side of the stirling engine is cold enough.

Also, as a stirling engine is a very inefficient thing to produce energy, a lot of energy is lost just because of the moving parts and the friction on those moving parts.

 

Another problem is that the glass won't be able to handle the heat generated by the array.

 

The idea of using a mirror array is not new though https://en.wikipedia.org/wiki/Concentrating_solar_power

[yordan 10]

OK, the wikipedia article is clear enough, the glass part is only for demo, and concentrating solar power for producing electricity is a good choice.
Now I understand why this thing was named "the air motor". Funnily, it's very efficient in cold countries, which is not the case with the standard thermic engines. It works with any heat source, like burning alcohol or burning pieces of woods or any trashed material. And realistic applications start coming.

Placed at the focus of a parabolic mirror a Stirling engine can convert solar energy to electricity with an efficiency better than non-concentrated photovoltaic cells, and comparable to Concentrated Photo Voltaics. On August 11, 2005, Southern California Edison announced[59] an agreement with Stirling Energy Systems to purchase electricity created using over 30,000 Solar Powered Stirling Engines over a twenty year period sufficient to generate 850 MW of electricity. These systems, on an 8,000 acre (19 km2) solar farm will use mirrors to direct and concentrate sunlight onto the engines which will in turn drive generators. Construction is expected to begin on the farm in 2010[60], although there are disputes over the project[61] due to concerns of environmental impact on animals living on the site.

[tansqrx 0]

Interesting plan that just will not work in the real world unless you target a very particular population such as the environmental activists. In a free market the number one factor in deciding what power plant to build is the relative cost of energy or how much money it takes to make one watt of electricity. Wikipedia has an excellent article on this at http://forums.xisto.com/no_longer_exists/

 

You can see that coal is by far the winner at 28-38 $/Mw (megawatt) which is why the US has hundreds of coal plants. Nuclear is also a good economic winner at 40-70 $/Mw. Some of the alternatives such as wind is 75 $/Mw, regular solar cells is 120 $/Mw (I would hate to have my local power come from this), and solar thermal is 85 $/Mw. It sounds like the sterling engine may be between the solar thermal and traditional solar at around 100 $/Mw.

 

This means that my electric bill which is now $200 for good ole coal power will now be $666.67. As far as Iâm concerned, I will keep coal and still be able to pay for groceries.