ELPC installed solar panels on the south-facing wall outside our headquarters on the 16th floor of the historic Jewelers Building in downtown Chicago. The installation was meant as a demonstration project for a variety of reasons, including its location on a historic landmark building; on a wall rather than a rooftop; and as a very small project requiring interconnection to the larger electricity grid. It was also one of the first solar projects to go through the City of Chicago’s green permitting program. Now that engineers, officials and historians have seen it, the next solar project will be easier, faster and cheaper — that’s ELPC’s ROI. I wrote, designed and provided photographs for this case study.