The city of Ellsworth is expected to become the biggest buyer for power credits generated by a 40-acre solar panel installation on Mariaville Road, where a New Hampshire-based developer plans to erect nearly 11,000 panels. The Ellsworth City Council this week is expected to OK a deal with SunRaise Investments, based in Portsmouth, New Hampshire, under which the city would buy credits for all the power generated at a 29-acre site on the east side of Mariaville Road, and credits most of the power generated at an 11-acre parcel on the west side of the road. SunRaise gained city approval in June to develop the two privately owned lots into solar farms that together would have a projected capacity of more than 6 million kilowatt hours per year.