pstarr wrote:Similar to propane or liquid petroleum (LP) gas, ammonia is a gas at normal temperature and atmospheric pressure but a liquid at higher pressures (about 150 pounds per square inch at 75 degrees Fahrenheit). So it can be stored and transported as a liquid but used as a gas.
It has half the energy density of gasoline. And ammonia is barely found in nature, certainly not in the same convenience and concentration of petroleum reservoirs. So how is it an improvement of propane?
It is not only about energy density. Any hydrocarbon requires carbon (so obvious), so it needs come CO2 recycling. In a sustainable close circle economy, in the future, CO2 could be obtained from biomass. But this has limitations by total (sustainable) production worldwide. Capture CO2 from air raises the energy requirements a lot. Hydrogen has been shown as the solution, but ammonia could be a better alternative as a whole. Although it has worse energy by weight, it has better energy by volume and it is easier to store.
For small cycles, batteries it is the obvious solution. But when we need to store high levels of energy, like season storage (from summer to winter, for example), fuel could be cheaper, even it requires to make greater energy capture (to compensate energy loses). Other solutions, like flow batteries could be ok.