Convincing customers that a long-term agreement for solar makes good fiscal sense requires facts and figures. I worked with the company's vice president of project finance to edit and revise a white paper on the financial benefits of off-grid solar energy. Using a statistical model, the paper predicts future on-grid electrical power rates and then compares those predicted rates with solar power purchase agreement rates (PPA) costs. Beginning with an outline and statistical data, I wrote a first draft that went through several cycles of edits and revisions. During the process, I learned a lot about stochastic statistical modeling, an interesting bit of knowledge but not one that I'll be likely to put to work again!