The question is how do you convert burning wood into electricity?
Sterling engine would be one way. You can also create steam pressure from the heat and spin a turbine.
Generally the same way you convert coal into electricity. Burn it in a large furnace and heat water into steam. Use the steam to produce base load electricity.
The drawbacks of biomass are: - the high moisture content of freshly cut living biomass (trees/plants), this dramatically reduces the efficiency. - large amounts of particulate pollution (unless expensive and complicated filtering and exhaust pollution capturing is included, again reducing efficiency) - enormous area needed to supply enough biomass to generate power. Coal and oil are very energy dense in comparison. E.g. The Drax power plant in the UK imports pelletized wood that comes from felling vast areas of hardwood forest in Canada and the US. The UK would not be able to supply enough wood to fire it.
If you were thinking of more of a household scale, then it might be a bit different. But you wouldn't be likely to produce electricity to live as you currently do connected to the grid where you can freely pull large loads without even thinking about it. You'd need to set up some system for converting the wood to power at a small scale. A complex steam turbine type operation would be large, costly, difficult to use and likely unreliable at that scale. As others have suggested, pyrolyzing dry wood into syngas/wood gas and using that to run in internal combustion engine would probably be the best bet at small scales, though that is not particularly efficient. I've thought about this a bit - base load energy generation off grid. Something like a reasonably large very low temperature differential sterling cycle engine. Something like that could be combined with solar water heaters so that the temperature boost required by the wood fired portion is only partial. Would take substantial effort to setup though, but something that could be useful in a zombie apocalypse kind of scenario.
Appreciate the thorough answer. I had a feeling it wasn't realistic, but really wanted to figure out why.
Same way with nuclear? It is all just heating water into steam and getting it to spin a turbine that spins a generator.
It is just really inefficient with wood.
Ineffecient alright, but in some areas greenwaste is plentiful. Perhaps a single residence electrical generator is unfeasible but I'm curious as to what the smallest scale that it might work, maybe if a small town put all it's biomass together.
The process undoubtedly could use improvement. Perhaps a catalyst of lye and aluminum.
It's called wood gas. During WW2 rural people used wood gas to power vehicles and machinery. Today you can use it to run a gas generator, which would create electricity. The downside? wood gas creates a lot of tar.
wood gas creates a lot of tar.
Good point. Could potentially pave some potholes with it. I hear Finns have learned to make pine tar edible somehow.
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