FLORVÅG, Norway — Framo has developed a submerged turbine to regenerate energy from waste cooling water flow on offshore installations.
Aside from allowing offshore operators to reduce their carbon footprint, the company said, the technology opens the way for increased gas exports. On offshore installations, large volumes of seawater are lifted from sea level to deck level for use as a cooling medium for onboard operations. The seawater is then dumped back to sea level from a great height.
The submerged turbine is designed for installation in the overboard water dump water line which, according to Framo, can generate electric power as the wastewater flows from deck level to sea level. The concept is based on the design of the Framo SE pump, used for seawater lift purposes offshore over the past four decades. As with the Framo SE, the submerged turbine can be installed in dedicated caissons; alternatively, a caisson-free version can be placed in guide funnels.
The turbine is said to be suited to both new projects and for retrofitting on existing facilities.
Tests have shown that the turbine can regenerate 20% to 30% of the energy used to lift the water from sea level to deck level. The generated power can contribute to the total power supply on the offshore facility, reducing gas fuel consumption for power generation on board, thereby cutting emissions (and CO2 taxes).
Therefore, more gas can be exported that would previously have been set aside for power generation.
Framo claims the technology will have the greatest benefit on offshore installations that require large amounts of cooling water or in areas with higher water temperatures.