Continued production of hydrocarbons from a well combined with co-production of significant amounts of hydrothermal fluids can sometimes be used to produce Geothermal Energy.
During oil & gas production, significant amounts of co-produced water are normal, especially from late life wells:
US oilfield data shows ~1 million wells have been producing ~21 billion bwpy (~58 million bwpd).
OGAUK well data shows several thousand wells have been producing ~1 billion bwpy (~3.4 million bwpd).
Normal operational practices have been to treat and dispose a lot of this water, but some amounts were reinjected, especially where water injection wells were used for production purposes. Reinjection is also recommended to minimize environmental impacts.
Some of this water is hot enough to be used in low enthalpy Binary ORC Power Generation where produced fluid temperatures as low as 100°C (212°F) are able to be utilized – the higher the temperature and flow rate, the more energy possible to be economically extracted. Water should be reinjected for pressure maintenance and thermal recovery of the recycled fluid;
Co-production allows continued economic production of smaller, end of life hydrocarbon production rates. Retrofitting modular, scalable Binary ORC power generation equipment allows environmentally sustainable increased value from some of these wells.