81893
According to the United States Department of Energy , the wide range of its current and projected uses , together with the lack of any immediately suitable replacement , makes dysprosium the single most critical element for emerging clean energy technologies - even their most conservative projections predict a shortfall of dysprosium before 2015 .
 United States Department of Energy
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 United States Department of Energy