Here's something the Colorado Clyde crew might come up with but I beat them to it with my Greenneck Solar Shootin System, a "Green" ignition system saving both caps and flint.
When loading or reloading your muzzle loader a solar panel attached to your hat will be charging the DieHard car battery carried on your back, this in turn is wired thru a set of Chevy points (opened and closed by the trigger) to 12 volt car coil which in turn is connected to an automotive sparkplug threaded into the bolster. Load up the old "Smokepole", hookup your battery and head in the woods. Upon seeing game take careful aim and pull the trigger opening the points, breaking the circuit causing the coil's magnetic field to collapse producing a brief surge of 25,000 volts thru the coil wire to the sparkplug producing the needed spark and BANG , your record Buck is in the bag.
Seriously, years ago I read about a gentleman who constructed 2 muzzle loadering pistols by using little model aircraft glowplugs as the igniter with a couple of D-cell batteries and push button trigger. They were simple needing only 3 volts from D-cells and worked but with some lag in firing and the glow plugs didn't last long but it worked.