it is something 25-year-old hannah alexander and her start- supole power are out to change. >> we make energy harvesting insoles for charging portable electronics while you walk. >> it has raised around half a million dollars so far and it being tested by the u.s. army. but alexander isn't alone in her desire for change. other start-ups vying to solve of the world's big problems are doing so not from silicon valley or alley, but pittsburgh. once a booming steel town has turned around post industrial collapse but never lost the spirit of innovation. pittsburgh is home to offices for google and apple and most rece uber but in the past decade the start-ups have been bolstered by techom cpanies has taken hollywood. >> the iron city is one of the most affordable places to live and work in america. that is part of the reason why the coffin foundation has ranked this a top ten metroor f established main street business activity with more than 1100 small businesses for every 100,000 residents in the area. innovation works, a nonprofit with two nationally ranked accelerate proper programs have