" Wood pellet ash is rich in potassium and certain micronutrients. It is also highly alkaline and has high acid neutralizing values. The author found that wood pellet ash added safely to compost at a maximum of

 5-15% of total compost weight can enrich it in a variety of nutrients".

 Everything has a value be it large or small. To some or all.

I heat with pellets, I save the ashes and give them to a friend for her chickens. She said they love to kind roll in them and peck at them. It is to be good for them.

Never really thought about making use of the ash.   There is very little left on the GMG and I usually do an annual clean out with the shop vac.     Maybe I will scoop it out and use it in the garden.     Biggest issue is ability to get the ash out without the shop vac.