The phrase "a relevant source of" is correct and usable in written English.
It can be used when discussing information, data, or materials that are pertinent to a particular topic or subject matter.
Example: "The research paper provided a relevant source of information for understanding the impact of climate change on biodiversity."
Alternatives: "an important source of" or "a significant source of".
"We do not see it being a relevant source of fuels over the next 20 years".
Waste can be a relevant source of energy thanks to energy-from-waste processes.
Anaerobic digesters and anaerobic sludge storage tanks can also become a relevant source of direct methane emissions.
The study of the insurance claims provided by this insurer is therefore a relevant source of data on the complications related to ambulatory surgery.
Meat is one of the staples of the human diet, which provides high-quality nutrients, but that also constitutes a relevant source of cholesterol and saturated fatty acids.
The after-sales activities are nowadays acknowledged as a relevant source of revenue, profit and competitive advantage in most manufacturing industries.
However, there are very few data demonstrating that resistance arising de novo within a patient is a clinically relevant source of drug failure in malaria patients.
Steel production is among the most energy-intensive industrial processes and is a very relevant source of CO2 emissions.
Because Carmen Santos's career was marked by numerous interrupted film productions, unfinished films constitute a very relevant source of information about her career.
McNulty, AL, Stabler, TV, Vail, TP, McDaniel, GE, and Kraus, VB. "Dehydroascorbate transport in human chondrocytes is regulated by hypoxia and is a physiologically relevant source of ascorbic acid in the joint". Arthritis and rheumatism 52, no. 9 (September 2005): 2676-2685.
Low-density polyethylene (LDPE) films, which are used in large volumes to protect agricultural crops, suppress weeds, increase temperature and retain irrigation water in the soil ('plastic mulching'), are a further relevant source of microplastics in the environment.
