Professor Timmons is an ecological economist, and teaches undergraduate and graduate courses in environmental and resource economics as well as microeconomics. He has also served as academic director for a study abroad program on renewable energy in Iceland. Professor Timmons is currently studying urbanization environmental impacts, looking at how environmental effects change when people move from rural to urban areas, or the reverse. He is also interested in the economics of renewable energy, and has studied potential production costs and impacts of biomass crops in Massachusetts. Other research has included local food system potential.