I want to convert from mass density to energy density:

  • Natural gas has a density of $0.8\: \rm kg/m^3$.
  • Biogas has $1.15\:\rm kg/m^3$.

I want to convert them into $\rm J/m^3$ so that I can compare the energy storage capacity for both fuels.


closed as unclear what you're asking by Bob D, Jon Custer, Thomas Fritsch, ZeroTheHero, Aaron Stevens Sep 12 at 19:20

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If you’re interested combustion energy, look up the enthalpy (heat) of combustion for each.

Hope this helps

  • $\begingroup$ yeah i did that for energy output, but now i want to analyze their storing capability, all the websites say biogas has low energy density so it cannnot store very well and i want the actual numbers. Can you help please? Thanks $\endgroup$ – Fred Weasley Aug 22 at 11:43
  • $\begingroup$ @FredWeasley It's likely that the variability in the heat of combustion is extremely large for biogas, corresponding to the large variability in its production processes. $\endgroup$ – Emilio Pisanty Aug 22 at 11:51
  • $\begingroup$ @EmilioPisanty can't we just use the values above? or maybe workout the range? ps thanks for helping $\endgroup$ – Fred Weasley Aug 22 at 11:54
  • $\begingroup$ @FredWeasley You asked for conversions, not what the issues are for storing each fuel. You can look those up also. $\endgroup$ – Bob D Aug 22 at 12:00
  • $\begingroup$ @FredWeasley You should be able to find estimates of J/kg. From there, using the density, it should be pretty straightforward to find how much energy it has per unit volume. You can just look at the units in this case and see what math you need to do to get from $\frac J{kg}$ to $\frac J{m^3}$ when you know $\frac {kg}{m^3}$. $\endgroup$ – JMac Aug 22 at 13:13

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