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Wood gas vehicles: firewood in the fuel tank

lowtechmagazine.com

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Re: Wood gas vehicles: firewood in the fuel tank

#21

Post by Yetanfou »

aidenn0 wrote: post #13
xyzzyz wrote: post #12

Earlier quoted context omitted.

There's a lot of energy in wood compared to coal. Wood has around 2/3 of the energy of coal by mass. What do you think coal is made from?

Isn't most of the mass of wood water?

Fresh wood contains ~50% water (up to 70% for certain species), 'dry' wood lies around 15% water. Depending on the type of gasifier you can feed it anything between fresh from the tree to kiln-dried wood. Starting a gasifier requires dry wood or charcoal but once it is going it will do a lot of the drying itself. The reduction process in the lower part of the hearth - where the gas production goes on, reducing CO2 to CO - can also reduce H2O to H2. The end product of a wetter wood will be gas with a higher H2 content next to the CO which forms the main combustible component in wood gas. Yes, wood gas is mainly carbon monoxide and as such highly poisonous, you do not want to start a gasifier in an enclosed environment nor open an unvented gasfier in such.

Re: Wood gas vehicles: firewood in the fuel tank

#23

Post by Synaesthesia »

averagewall wrote: post #16

Important downside explained half way through: "if we were to convert every vehicle, or even just a significant number, to wood gas, all the trees in the world would be gone and we would die of hunger because all agricultural land would be sacrificed for energy crops."

In the last years of WW2 I think Japan chopped down the last of its trees to make a bit of aviation fuel.

Re: Wood gas vehicles: firewood in the fuel tank

#24

Post by adrianN »

clord wrote: post #2

Nice thing about wood power is that as long as you have a sustainable source of wood, you're 100% solar-powered and carbon neutral. That is to say, it's a source of energy that is (can be) non-fossil, nor derived from any fossil sources, and which recycles it's own CO2 emissions. There are very few other alternatives that can claim the same. Perhaps Hydro? Solar panels don't offset their construction CO2 costs, and i…

If you turn the wood to charcoal and only burn the syngas, it's even carbon negative. Charcoal is stable for hundreds or thousands of years when buried. It also improves the soil.

Re: Wood gas vehicles: firewood in the fuel tank

#25

Post by weinzierl »

garrettgrimsley wrote: post #5

I saw some of these in use while visiting DPR Korea. We weren't up close, but the government tour guide confirmed that they were wood-burning trucks. Sadly I was not allowed to photograph the trucks. Like the article mentions, deforestation is an issue they can cause, something Korea suffers from greatly.

When resources were scarce during WW II in Germany there were various kinds of wood gas vehicles. Here is a video of a 1942 tractor:

https://m.youtube.com/watch?v=RMVwbjp514o

Re: Wood gas vehicles: firewood in the fuel tank

#26

Post by flyGuyOnTheSly »

garrettgrimsley wrote: post #5

I saw some of these in use while visiting DPR Korea. We weren't up close, but the government tour guide confirmed that they were wood-burning trucks. Sadly I was not allowed to photograph the trucks. Like the article mentions, deforestation is an issue they can cause, something Korea suffers from greatly.

>Like the article mentions, deforestation is an issue they can cause, something Korea suffers from greatly.

To be fair, that is something that almost every single developing nation in the history of human kind has suffered from greatly.

Re: Wood gas vehicles: firewood in the fuel tank

#28

Post by imbur »

clord wrote: post #2

Nice thing about wood power is that as long as you have a sustainable source of wood, you're 100% solar-powered and carbon neutral. That is to say, it's a source of energy that is (can be) non-fossil, nor derived from any fossil sources, and which recycles it's own CO2 emissions. There are very few other alternatives that can claim the same. Perhaps Hydro? Solar panels don't offset their construction CO2 costs, and i…

Gasifiers can run off of many types of biomass. Corn husks and other agricultural waste is a big source besides wood.

Re: Wood gas vehicles: firewood in the fuel tank

#30

Post by beobab »

imbur wrote: post #29
mrfusion wrote: post #6

Would a steam engine make more sense? Then you could run it on anything.

You can run a gasifier out of almost any biomass, coffee grounds, wood, leaves, corn husks. Then with minor modification you can run most cars on the resulting syngas.

I want one of those "Mr Fusion" devices from Back to the Future for my car (and my house too, now I think about it).
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