A red traffic light is seen next to the headquarters of Germany's Deutsche Bank in Frankfurt, Germany, January 26, 2016. Kai Pfaffenbach | Reuters

More than a dozen European banks facing exposure in excess of $100 billion to energy sector loans may need to sell assets to bolster against future losses. Potential buyers of those assets include a mix of large private equity firms, a select group of pension investors, U.S. banks and hedge funds. Due to the recent decline in major European banks' shares and increasing scrutiny over the bad loans the banks hold, investors are starting to gravitate toward the idea of getting actively involved in European banking names. "European banks are under pressure because they have to continually raise capital ratios" in order to offset troubled loans, Julien Jarmoszko, senior investment manager at S&P Capital IQ, told CNBC.com. "We're seeing more restructuring being initiated." The cash crunch is in part due to slower management of post-crisis and regulatory issues that European banks faced several years ago. It just happens to be coming home to roost at a crucial time, both in terms of banks' share prices and at a time when liquidity issues are threatening investors globally. "U.S. banks were faster to raise capital, raised more of it, strengthened balance sheets and restructured faster" than their European counterparts, CLSA bank analyst Mike Mayo said. Read MoreBank investors have suffered two lost decades The four U.S. banks with the highest dollar amount of exposure to energy loans have a capital position 60 percent greater than European banks Deutsche Bank, UBS, Credit Suisse and HSBC, according to CLSA research using a measure called tangible common equity to tangible assets ratio. Or, as Mayo put it, "U.S. banks have more quality capital." Analysts at JPMorgan saw the energy loan crisis coming for Europe, and highlighted in early January where investors might get hit.

"[Standard Chartered] and [Deutsche Bank] would be the most sensitive banks to higher default rates in oil and gas," the analysts wrote in their January report. In fact, on Monday, Standard Chartered stock fell more than 27 percent intraday for the year, and Deutsche Bank stock had dropped more than 37 percent in a tumultuous trading day in Europe and in the U.S.

European banks may need to hasten asset sales to generate provisional capital; the problem is exacerbated because, although EU banks have exposure similar in size to U.S. banks', most have less in total assets than their American counterparts, magnifying the damage. Read More The three largest U.S. banks' energy exposure, according to a Goldman Sachs analyst report, represents less than $60 billion in loans and is divided among Bank of America, Citigroup and Wells Fargo. But those banks together also manage nearly $6 trillion in total assets. While BNP Paribas' balance sheet is more comparable to that of the major U.S. banks, others within the EU banking sector, like Standard Chartered, Credit Suisse and UBS, are substantially smaller. So the $9.4 billion and $6.1 billion in energy loans weighing on Credit Suisse and UBS, respectively, may have a greater impact on those banks, Jarmoszko said. "[W]e will see losses," he said, "but UBS generates $6 billion in pretax pre-provisions so they will cover these through earnings without damaging capital."