I am interested in this position for several reasons

I am interested in this position for several reasons. The first reason is  because I am passionate about this type of work; its something I very much will enjoy doing, and the skills and qualities I possess will mean I will add value in your company in this role. I'm also interested in this job position because  having researched your your company, I am attracted to your values, your track record of achievement and the fact that you clearly have ambitious plans for the future.

This position, if I am successful is the one I can see myself working in for many years to come with growing both personally and professionally.