Christian Science Monitor: George and Judith Reilly own a big antique house on the main street of Brandon, Vt., a picturesque town on scenic Route 7. The house’s front parlor doubles as a gallery to display the fabric art Judith creates in her upstairs studio. Last spring, when oil for the house’s furnace began to top $4 per gallon, Mr. Reilly did some quick calculating and decided he could save up to 50 percent on his heating cost this winter by installing a stove that burned sawdust pellets. Over the summer, …