Replies

1. Expert Member
   Zephyr7|Jan 12, 2020 07:40pm|#1

   Probably not much since there isn’t much hydrogen infrastructure out there. Hydrogen doesn’t have particularly good energy density, and the metal embrittlement issues are a big problem too.

   If you’re thinking of hydrogen as a green energy source it’s really not. There are three reasons for this:
   1- it is sometimes made by processing natural gas. In this case, you’d be better off just using the natural gas directly. Anytime you change the form of energy, you lose some of it, so maximum efficiency is always when you use the energy source as directly as possible.
   2- it is sometimes made using electrolysis to split hydrogen out of water. This is typically not a very efficient process, and uses grid electricity, so you’d be more efficient to just use the electricity directly.
   3- hydrogen is not a primary energy source. This means hydrogen is never found in a ready to use state. Primary energy sources are things like natural gas, oil, nuclear, hydroelectric power, solar, etc — you get the energy directly from the energy source. Hydrogen is more like a battery, energy was CONSUMED to make the hydrogen out of something else, then you used the hydrogen to supply energy. The hydrogen wasn’t where the energy originated, in effect. This leads to the same efficiency losses mentioned in #1 and #2.

   Hydrogen is usually talked about as a possible transportation fuel where you need something mobile. This is a better use for it than a stationary device, but there are still a lot of issues with the transport and use of the hydrogen itself. You have the metal embrittlement issues I mentioned that make metal parts prone to fracture over time, and you’re dealing with either a very high-pressure or cryogenically cooled liquid. Either wants to flash to an explosive gas.

   Bill

2. Expert Member
   Akos|Jan 12, 2020 08:17pm|#2

   我在燃料电池行业工作15年ago. At that time, the hydrogen economy was "15 years out". There has been a lot of progress there, but that 15 years out doesn't seem to ever change.

   But like Bill said, the big issue is where to get hydrogen from. Producing it from grid is 75% efficient, if you are looking for long term heat storage, you are better off to go with a large tank and a resistance element.

   If the hydrogen is made from natural gas, then might is well burn the natural gas directly, it is more efficient.

3. 
   Ryan Lewis - Zone 4A|Jan 12, 2020 08:30pm|#3

   Got it thanks!