Dresser-Rand provides a complete range of combined heat and power (CHP) solutions and aftermarket services to commercial, industrial, and municipal energy users worldwide. CHP systems reduce on-site energy costs and carbon dioxide emissions through the highly efficient delivery of power, heating and cooling.

Boston Scientific Corporation, which has headquarters in Natick, MA in the US, was the first Massachusetts-based company to respond to the governor’s Clean Energy Challenge. This calls for local businesses to reduce their greenhouse gas emissions by 10% over the next three years. Boston Scientific accepted the challenge by investing in a solar-trigeneration system for the Marlborough, MA facility.

This trigeneration system was designed and manufactured by Dresser-Rand and was installed in August 2010. Boston Scientific’s facilities experts and project managers organised the 40-week design/build project and saw it through from factory build to commissioning, with assistance from outside engineers, contractors and two local utility companies.

In combination with the renewable solar thermal energy, which comprises the combined cooling, heating and power (CCHP) systems roof assembly, the system will generate approximately $300,000 in energy savings each year.

Operating at approximately 80% efficiency, the system compares favourably to grid power, which can be as low as 35% efficient at the generation point, with an additional loss of 7-9% in the transmission and distribution phases.

This dramatic increase in energy efficiency for the site will reduce CO2 emissions by approximately 1,700 tons per year. In CO2 reduction efforts, this is equivalent to planting approximately 359 acres of pine and fir trees.

Unique approach

"Boston Scientific recognised that its unique blend of energy requirements needed to sustain and propel its cutting-edge pharmaceutical R&D and manufacturing processes would require a unique approach to energy conservation and environmental stewardship," says Stephen Zilonis, VP Business Development for Dresser- Rand CHP group. "Now more than ever it’s important that commercial and industrial energy users maximise their fuel efficiency," Zilonis continues. "One way to achieve that is through this type of properly applied distributed generation."

A CHP, or cogeneration system, offers an environmentally friendly option for providing power and energy where it’s needed through the simultaneous generation of usable heat and electricity.

Trigeneration is the simultaneous production of electric power, heating and cooling. The absorption chiller (no chlorofluorocarbons or CFCs) is assembled with all the necessary pumps, heat exchangers and controls, in an engineered package consisting of the same construction as the matched CHP unit.

The site’s existing HVAC cooling tower system, controlled by the integrated trigeneration control and monitoring system, provides cooling of the absorption chiller package and engine system when required. Facilities personnel do not have to intervene for daily operation of this cooling tower.

Solar power

Dresser-Rand’s trigeneration systems are designed to match client requirements for electricity, heating and cooling precisely.

At Boston Scientific the performance of the trigeneration system was further supplemented by a solar thermal array roof design, which delivers additional heat to the system’s primary hot water circuit for transfer to either the heating or cooling demands of the facility.

Boston Scientific’s 555kWe-130 USRT unit provides continuous, on-site-generated electricity, heating and cooling to its office and R&D facility from a single, natural gas fuel source. The unit is capable of delivering 3.6 million BTUs of hot water at 180°F (82°C) or up to 130 tons of chilled water via an absorption chiller. These outputs are designed to provide about 20% of the site’s cooling demand and 35 percent of its hot water demand on a typical day.

The unit is fuelled by clean natural gas and, by using a catalytic converter system, achieves emission levels well within EPA guidelines.