I do at least 3 or 4 a year. All but 2 have related to technology implementation, manufacturing operations, manufacturing engineering, and new business start-up. One dealt with an economical way of collecting and processing 37 million pounds/year of chicken carcasses from the many chicken farms in rural SE OK. Another dealt with chicken poop!
All of the above comments are excellent. I may add that, if possible, you should relate all costs and benefits to a common denominator - $$. Whether you're dealing with for-profit or non-profit proposals, the bottom line usually is $$. If the value of the benefits (you may have to be creative here) exceed the costs, then the project is economically feasible.
I use Excel spread sheets to identify and manipulate the quantifiable elements.
Good luck.