Margaret Chase Smith Federal Building

At a Glance
• System Configuration: 1 × C65 Grid Connect Capstone Microturbine integrated with BAS controls
• Annual Generation: >500,000 kWh/year of clean on-site electricity
• Thermal Output: 430,000 BTU/hr of recovered hot water for facility heating loops
• Financial Impact: ~$50,000 / year in annual energy cost reductions
• Sustainability Milestone: Key contributor to earning LEED Platinum certification (GSA’s first in New England)


The Challenge
Originally constructed in 1967, the 188,000-square-foot Margaret Chase Smith Federal Building and Courthouse in Bangor, Maine, housed key federal agencies, courts, and administrative offices. Facing outdated, inefficient 1960s building infrastructure, the U.S. General Services Administration (GSA) launched a comprehensive five-year modernization initiative. The goal was to transform the high-load municipal asset into a state-of-the-art, energy-resilient green building while achieving strict federal decarbonization and LEED efficiency benchmarks.


The Solution
As part of the whole-building energy overhaul, a 65 kW Capstone Combined Heat & Power (CHP) microturbine system was commissioned to operate in synergy with a geothermal HVAC loop, rooftop solar PV, and advanced Building Automation System (BAS) controls.
• On-Site Baseload Generation: Produces over 500 MWh of reliable electricity annually, reducing dependency on grid power and lowering peak demand costs.
• Thermal Energy Integration: Captures 430,000 BTU/hr of exhaust heat to supply continuous hot water for building hydronic space heating, complementing the geothermal HVAC system.
• Low-Emission Municipal Reliability: Features oil-free, air-bearing turbine technology with a single moving part, ensuring minimal maintenance, clean exhaust, and whisper-quiet operation within a active federal courthouse.
• Grid-Synchronized Efficiency: Operates seamlessly in grid-connect mode to optimize real-time energy dispatch alongside on-site photovoltaic solar generation.


The Results
• $50,000 Annual Savings: Delivers consistent recurring utility savings, directly benefiting municipal and federal taxpayer operating budgets.
• LEED Platinum Certification: Served as a core distributed energy asset that enabled the facility to become the first GSA building in New England to achieve LEED Platinum status.
• Decade-Plus Proven Performance: Has provided continuous, clean power and thermal energy to the federal facility since its 2012 commissioning.
• Comprehensive Decarbonization: Drastically reduced facility greenhouse gas emissions by maximizing fuel utilization through dual electricity and heating generation.