Honeywell Refrigerant Helps ConvertSunlight into Electricity

May 19, 2010
Fuel isn’t burned to create the electricity, therefore the unit doesn’t produce carbon dioxide emissions.

Honeywell’s Genetron® R245fa refrigerant is being used to help homeowners generate electricity from the sun's heat while offsetting energy costs. This energy-efficient refrigerant is being used in an organic rankine cycle (ORC) called the 35Z Micro Power Plant, manufactured by the Germany-based company, Turbolina.

(The Organic Rankine cycle (ORC) is named for its use of an organic, high molecular mass fluid with a liquid-vapor phase change, or boiling point, occurring at a lower temperature than the water-steam phase change.)

The 35Z Micro Power Plant uses water heated by thermal solar panels to evaporate the refrigerant, which in turn drives a turbine to generate electricity. Fuel isn’t burned to create the electricity, therefore the unit doesn’t produce carbon dioxide emissions. The remaining heat from the 35Z can be used to supply heating and hot water.

"When we began designing the 35Z, we knew we needed a reliable, low-temperature working fluid, and Honeywell's R-245fa refrigerant was the perfect choice," says Hermann Helmbold, general manager of Turbolina. "The 35Z is a source of energy that helps homeowners both reduce their carbon emissions and become independent from traditional sources of energy."

R-245fa is non-flammable, non-ozone-depleting and has low toxicity. The heat transfer properties of Honeywell's R-245fa, including its low boiling point of 59.5 F (15.3 C), makes it ideal for use in ORC systems that use low-temperature heat and waste heat to generate electricity.

"This unique application is a great example of how Honeywell technologies are helping homeowners become more energy-efficient," says David Diggs, global business director for Honeywell Fluorine Products. The 35Z’s electrical power output is 3.5kW, which is ideally suited to the needs of homeowners.

Turbolina specializes in the development, production and sale of ORC systems that convert low temperature heat into electricity. The company offers ORC technology in sizes up to 500KW to meet the needs of differing heat recovery opportunities. For more information, visit