Portable Steam Engine

[JAK]

Couple of crazy ideas.

First idea is a small teardrop trailer than could be towed behind a ATV or Skidoo. Basically just a well insulated sleeping compartment, perhaps with a tailgate that opens up into a galley kitchen. Second idea is an electric ATV that can be recharged using wood fuel while encamped. Perhaps a very small steam engine, in addition to a few solar cells. The idea would be to cover only a few miles each day, and not all that quickly, but quiet enough to be able to carry on a conversation.

Using this as an example:
http://www.gorillavehicles.com/GorillaSpecifications.htm

If you ran the 180# of batteries 5 hours at 24v x 25amps that would be 3 kwh. Not sure how far you might get. Perhaps the teardrop trailer might have some solar panels for some extra boost, as long as the sun was overhead. Anyhow, to recharge you might need to generate about 4-4.5 kwh, perhaps as little as 400w over 10 hours, or as much as 1500w over 3 hours. The smaller charge rate would take longer, but it would be lighter and more efficient at recharging the batteries. Perhaps a simple single stage steam engine. It wouldn't need to be all that efficient, perhaps 12-15%. The extra heat could be used for cooking. The tricky bit might be the boiler, and some sort of a condensor. It wouldn't need to be capable of operating at high pressure. Atmospheric might be good enough, as long as you could generate a good vacuum. The critical limitation might be that you would need to reasonably good water source for boiler water and cooling water, and it would need to be able to operate with undistilled water.

So, going back to the early logging days, were there any small portable steam engines and boilers that might be made even smaller?

[JAK]

Perhaps running a small generator on wood gas might be the better way to go. So the question would be how light and portable and reasonably efficient one might build a small wood gasifier, engine, and DC generator. Either way, if it could generate 4 kwh, at 5-10% efficiency, that would mean about 20-40 pounds of wood. Seems like a lot of wood, and a lot of work. Might be fun in winter though when you might want to burn the wood anyways.

[JAK]

Generalizing the problem some more, what is the most portable system for generating 4kwh of energy from wood, solar, or wind power? Of course wind power might not always be reliable, but wood or solar might not either, depending on where you are. I was also thinking of some sort of rocket stove that generates electricity using thermistors. Anyhow, I'm starting to think that something as old and simple as animal power might be hard to beat for such an application, be it sled dogs, shetland ponies, goats, whatever. Then there is also true democracy (people power). Not such a new idea eh.

Anyhow, it would be interesting to see a detailed analysis in terms of efficiency, reliability, maintainability. I will keep working on the rocket thermistor stove powered dog sled, just for the fun of it but I don't think I'll be a serious contender for the Ididerot any time soon.

[jott]

I think you are running into why oil is such a dominate source of energy. Not much else has the same energy density. My guess for best option would be a small gas engine running on wood gas. Converting energy to electricity then storing it, then back to mechanical energy adds in lots of losses. For steam you can get a small steam engine that will easily power your ATV. Old Stanly steamer engines are surprisingly small and light. Many old boat steam engines would also work. But with steam you need a boiler and with wood it will need to be big, the energy density just is not there for wood and if you are using oil that seems to be missing your point. Also with steam water is a problem. You need a lot of it, or a condenser both take up space and adds lots of pounds.

I think you are right with that animal power mite be the best choice.

[AlchemyAcres]

"The idea would be to cover only a few miles each day"


Is that the only goal here...or are you just tinkering around? Nothing wrong with tinkering.....

What's your ultimate goal? Walking, snowshoeing , cross_country skiing or even sled dogs deserve consideration.


~Martin :)

[JAK]

What I had in mind, at least initially, was some sort of mobile camp, or even a small mobile homestead. Like a gypsy camp, but perhaps between one small plot of land I might own and others I might own, and perhaps some crown land in between here and there for short stays, or longer squats. Old gypsy caravans come to mind. Coverered wagons also. Also dog sleds. All of which animal power does seem to be particularly well adapted. Camel caravans also I suppose. A sailboat would be another option, if by sea.

On land, solar might work in theory, but only if you travelled very light and were willing to stop for a day or two to recharge before moving on. Perhaps an electric motorcyle with a small trailer, on paved back roads with modest speed limits. The ATV on logging roads or ATV roads came to mind because it opened up opportunities of slower more efficient speeds, and many places to go away from crowds. There is quite a network of such roads in places like New Brunswick and Maine. Of course the canoe also works well in North America, if you don't mind portaging. Trouble is not so much the occassional rapids or portage but cities and people that get in the way more than they used to. Still, on river systems a solar powered canoe is an attractive possibility.

In general, I think it would be very useful to consider having a homestead well connected to such things as river systems and logging roads, and some means of moving camp, or moving goods for trade etc, or foraging materials from such routes, by such means. Off the beaten track so to speak, but still well connected. Historically in New Brunswick the St. John River was the highway, and is likely to become a highway again. A small homestead on the river, backed by woods, both private and crown land, with perhaps some shetland ponies or larger beasts, and a woodboat for trade and travel on the river and down to the Boston states. That was the way it was done not too far back. Before them it was birch bark canoes, on both river and sea. Today it is the same thing but with tractors and trucks. I guess I'm thinking the highways we've built more recently will still be useful, but the older ways and means should not be forgotten, and some modern technologies might be adapted to them, or not.

[DavidOH]

Once in a while steam engins come up, so I post this:

http://www.tinypower.com/electric.htm