Let's do back of the envelope calculations:
Great Pyramid of Giza weights 500.000 tonnes. It is 146 meter high. It's center of gravity is at 1/4 of it's hight, 36m. It's potential energy is about 50 MWh.
These guys claim that they can store 35MWh in their tower. Basically claiming that they can build the pyramid in a day and take it apart at night.
So you pyrolyze wood to make wood gas, burn that gas to get CO2, then invest energy to make methane which you can burn later on? Well sure, but why not use wood and wood gas directly?Because using wood that way isn't "renewable"/"CO2 neutral" according to the climate agreements?
Actually, wood isn't very compact, so converting the wood gas to methane (which is already widely used in e.g. buses) would be simply a fuel refinement process.
I do know that CO2 sequestration from ambient air is nontrivial, and typical concentrations (0.04% per volume) are so low that the methane-generating processes cannot realistically rely on CO2 from ambient air.
A pyramid is a relatively stable shape. The Egyptians were a fairly clever lot, so you can bet they realized a pile of sand settles in pretty much that shape because it's quite stable.
Wood gas doesn't contain much CO2.
Gasification is a good idea though and can be used to convert dry, organic waste such as nut shells or corn cobs, to a fuel which can be burnt to produce heat and electricity.
Let's do back of the envelope calculations:
Great Pyramid of Giza weights 500.000 tonnes. It is 146 meter high. It's center of gravity is at 1/4 of it's hight, 36m. It's potential energy is about 50 MWh.
These guys claim that they can store 35MWh in their tower. Basically claiming that they can build the pyramid in a day and take it apart at night.
Just checking that it looks like you may be out by an order of magnitude. Apparently the pyramid masses approximately 5,200,000 tonnes.
Another downside of wood gas (and producer gas) is that the CO content makes it deadly.
Let's do back of the envelope calculations:
Great Pyramid of Giza weights 500.000 tonnes. It is 146 meter high. It's center of gravity is at 1/4 of it's hight, 36m. It's potential energy is about 50 MWh.
These guys claim that they can store 35MWh in their tower. Basically claiming that they can build the pyramid in a day and take it apart at night.
Just checking that it looks like you may be out by an order of magnitude. Apparently the pyramid masses approximately 5,200,000 tonnes.True, the weight is 5 million tonnes. I am one order off.
Power to gas uses power to do this reaction:
2 CO2 + 4 H2O = 2 CH4 + 3O2
Natural gas is mostly methane.
Power to gas (P2G) is not done in the industrial scale, but there is a 100 MW plant being built in Germany. I think others will follow. And methane can be used in many other ways than just power generation. My favorite part about P2G is that it is actually reverses the CO2 emissions and global warming.
Where does it get the CO2 from?
Wood gas doesn't contain much CO2.You missed the "burn that gas" bit.
QuoteGasification is a good idea though and can be used to convert dry, organic waste such as nut shells or corn cobs, to a fuel which can be burnt to produce heat and electricity.Wood gas was widely used in cars during the second world war in this part of the world, due to fuel shortages. The downside was the size of the fuel, really, because the wood gas was generated in situ as needed. (In particular, that cylinder/"tank" you see in those vehicles is the generator; the gas itself is not stored at all.)
If, for some reason, we absolutely had to stop using gasoline and diesel for vehicles, switching to wood burning would not be that big of an issue. "Mad Max" simply would not happen anywhere you got trees aplenty; people would just tinker a bit with their cars, add funky silly-looking gasification canisters, and go on with their lives. Like they did here in Fennoscandia during the second world war. Fuel use for a practical four-door sedan is 50 - 100 kg of firewood per 100 km travelled.
That said, you can burn even trash for heat and energy just fine. Just look at Sweden, for example.
That said, you can burn even trash for heat and energy just fine. Just look at Sweden, for example.
Burning biogas will give less energy, than just burning the rubbish, since only biodegradable material will produce methane and burning the rubbish will use all of the organic material. The only advantage of biogas is it doesn't release so much carbon dioxide, as the carbon in the buried non-biodegradable matter remains their for all eternity.
Burning biogas will give less energy, than just burning the rubbish, since only biodegradable material will produce methane and burning the rubbish will use all of the organic material. The only advantage of biogas is it doesn't release so much carbon dioxide, as the carbon in the buried non-biodegradable matter remains their for all eternity.Burning the rubbish requires complex capture mechanisms to avoid a whole bunch of nasty things in the trash being emitted from the flue, so there is a tradeoff.
Oh so you mean make wood gas, burn it, presumably to generate energy and use that to convert the CO2 generated and water to methane and oxygen? That would result in less energy than simply burning the wood gas in the first place, as it will take energy to convert the CO2 to methane.
Yes, wood gas used in the war, instead of petrol to power cars, but not very many people had cars back then.
It would make far more sense to go electric instead.
The waste should be separated into recyclable, biodegradable and non-biodegradable first.
OK. Apply a minimum of "thought" and see if you can propose a design that might work.This or a variant of it self centres when roughly placed and is already designed to be hard to break and fit while worn.Try stacking those 150m high, when they start to get beaten up a bit, and see how far the stack tilts.