What is energy density of Ethylene?

I am looking at fuels for Mars Rovers.
Methane/Oxygen produces 2,800 W-hr/kg (or 2,380 W-hr/liter of fuel / oxidant carried). However, Methane has to be pressurized to remain liquid under Mars conditions.
Ethylene is much easier to handle on Mars. What is it's energy density?
Asked Jan 06, 2010

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