Commercial Utility Recovery and Savings Companies...how do they do it?

We had a company come in today to our business and claim to help us reduce our utility costs by finding errors from the past and apply for refunds, making sure we had the lowest rates possible from the utility companies, look for tax credits and rebates, etc. Is there not a way for us to find this information online without having to us one of these companies?? If so...how do we find it for free??? Do we haggle our electricity providers for cheaper kilowatt rates because we have been in business since 1972? Do we ask for a historical report to look over and they just hand it over to us for free??? How does this work for a mid-sized company?