Money only have the value that people decide they have. Cutoff from civilazation in the arctic, holding a wad of dollarbills won't make you able to buy a service by itself. Having an energy source in the same situation could most likely make you able to buy something by 'selling' energy for favours or goods, though.
Actually, the same can be said about energy. How much value does a trillion gigajoules of stored energy have if you're stranded on an lifeless planet and about to run out of food? Energy only has value if you can do something with it. The same is true about time, by the way. People say "time is money," but that statement is not literal - we can't sell the two hours we're stuck at the airport, nor can we buy back the hours we wasted on internet forums for any amount of money.
More than that, it's the only thing that has static value no matter where you are in the universe. Assuming the laws of physics don't change over distance, the energy needed to accelerate an object to 30mph is the same no matter where you are. Sure, local conditions can affect that (it's easier to accelerate in low gravity, for instance) but it's still the same amount of energy, just from different sources.
Nothing has "static value," because the economic value of something depends not just on what you can physically do with it, but on what you can
exchange it for, and what you can exchange it for depends on how much there is and how much people need (supply and demand). Things only have value relative to other things. Sure, the physical properties of the energy itself stay more or less the same no matter where you are. But that's not the same as it having the same value, because the actual work you can do with it doesn't have the same value. That acceleration to 30mph you mentioned might be very useful in some places and worth nothing in others. A huge pile of energy is very valuable if you're surrounded by machines that can turn it into useful work, and worthless if you're on a broken ship billions of miles from civilization.
These are extreme examples, but they illustrate the point that energy, just like everything else, has a value that goes up and down depending on circumstances. What makes energy a bad currency is that (setting aside portability issues which technology might solve)
its value goes up and down frequently and unpredictably. It's like using dice to determine your economic policy.
If you could directly convert energy into matter of any kind and in any shape, then yes, you could "trade" energy for any (physical) thing. But
even then it wouldn't have a static value, because its value relative to various services and intellectual property would be variable.
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