Use journals to find academic studies and other scholarly research. All of the directories listed on this page are open access, meaning you won't need a subscription or affiliation with a subscriber to access content. Be aware that not all journals are created equal, even the ones flagged as "scholarly." As with any source, ask the following questions about each article you find:
Since you won't have access to Yale University's research databases, Google (and especially Google Scholar) will be your friend! Not everything you'll find through Google Scholar will be accessible, but you may be able to use your public library's interlibrary loan service, and you'll be able to see how many citations an article has accrued since its publication (a good indication of an article's importance in a field of study!)
You can also limit your regular Google search to specific domains such as .edu and .gov by typing site: [domain] [search term]
For example: site: .gov energy