The work marks the start of a project to remove five of the massive tanks to create a solar panel installation capable of generating 1.2 megawatts of electricity, the utility announced.
The tanks, empty for many years and long seen as a local eyesore, are located on SIG’s industrial site at Le Lignon in the municipality of Vernier.
They are scheduled to be demolished by the end of the year when construction will start on the photovoltaic plant, designed to generate enough energy from the sun to power 400 households.
The removal of the tanks will free up 7,500 square metres of space to install 4,200 solar panels, SIG said in a news release.
The power from 7,500 square metres of panels will be used by SIG to boost the amount of solar electricity it produces to meet 65 percent of what it consumes, up from 25 percent.
The cost of the demolition is estimated at 410,000 francs ($440,000) most of which will be recouped through the sale of steel recovered from the tanks.
The cost of the solar panel installation was not disclosed.
The installation is about half the size of the largest one in Switzerland, which was inaugurated earlier this month by SIG on the roof of the main building at Palexpo, the Geneva exhibition centre.
The utility invested 15 million francs in that project, boosting its output of solar power by 50 percent in the process.
Solar power still accounts for a tiny fraction of the electricity supplied by SIG to customers in Geneva, most of which is fed by transmission wires from sources outside the canton.
But the Mayor of Vernier, Yvan Rochat, sees the removal of the fuel tanks as a concrete sign of the move away from fossil fuels to renewable energy, according to the Tribune de Genève newspaper.
Another plus for the municipality, said Rochat, is that the removal of the fuel tanks will free up more land for residential and commercial buildings, which up until now have not been permitted in the area for safety reasons.