The Occupational Safety and Health Administration 10-hour Training Course in generally a requirement for construction labor. Many solar integrators require that their installation labor employees take this course and hold a valid card. Project managers are generally asked to hold a Construction Supervisors License (CSL) and/or OSHA 30. As the entry-level into the solar industry continues to become more competitive, employers will ask prospective employees to show greater levels of certification and/or more specific colleges degrees to fit growing roles at top companies.
Already, in many areas where the solar industry is mature, a passion for solar energy is just not enough to get your foot in the door anymore. Aside from OSHA 10, many employers also want to see their installation labor or project managers holding a NABCEP (North American Board of Certified Energy Practitioners) Certified PV (or Thermal) Installer Certificate. NABCEP certifications show that an individual has achieved a high faculty in the understanding of the design and installation of either solar PV or thermal systems. NABCEP makes the case for certification on their website.
Even among office staffing, more companies are looking for graduates from top-tier institutions, advanced degrees, and prior experience in solar in their hiring decision process. Of course, much of this is probably also driven by the "buyer's market" effect due to high unemployment rates. Browsing Craigslist locally in most metro areas under jobs filtering by "solar" you might easily find a company looking for a senior-level engineer who will also provide a number of customer service functions or something else similarly extremely specific or a listing for a marketing associate requiring an MBA.
As our industry continues to mature, there will be a lot of shake-down in the certification and qualification profiles required by employers. Right now, it is clear that certifications have their advantages to help stick out from the crowd of applicants.