What should I say to the professor?

Contact the DOE in writting and explain your predicament. I have no idea what area of energy studies your degree is in but they are bound to have something else to offer. If it requires another university, then relocate. Try not to interrupt or delay your Phd program if possible. You have had a tough break but you are a valueable asset as a graduate student and shouldn't forget that. There is a school that will accommodate you and will feel lucky to have you. Do it ASAP.