The Press and Journal
A Scottish Water site in Aberdeen has transformed its carbon footprint and increased its green energy production by generating power from waste water.
Following upgrade work at the Cambi thermal hydrolysis plant, which was installed 20 years ago at Nigg Waste Water Treatment Works, the company has now halved its CO2 emissions since 2019.
The improvements have allowed additional sludge to be treated on site, increasing the amount of biogas produced by between 25% to 30%.
This has enabled more green energy to be generated, as well as reduce the amount of fuel oil used to power the boiler – cutting around 1,300 tonnes of CO2 emissions and saving more than £250,000 per year.
It has also prevented thousands of tonnes of sludge from going to land recycling where it would release harmful methane gas.
The site is now able to consistently produce between 80 to 90% of its electricity needs through two Combined Heat and Power (CHP) engines, with periods where it is also exporting excess power to the national grid.