The compact city car fleet will be used to deliver meals on wheels to up to 30 households every day, and to ensure the meals remain warm, all of the C1s have been converted to be capable of carrying four insulated boxes.
Hertfordshire Community Meals (HCM) delivers meals to residents across the county and Sarah Wren, Chief Executive confirmed the need for low-cost, small cars capable of weaving through city traffic.
She said: "The Citroen C1s will help us to deliver an excellent service to our customers, whilst reducing energy consumption and reducing our costs.
"Also, their small size and good visibility means our drivers will find them easier to manoeuvre and park in narrow streets."
The Citroen C1s will join the fleet of Citroen Berlingo First vans already used by the HCM team in the local area to deliver the meals to elderly and disabled people.
The benefits of using the Citroen C1 are clear; CO2 emissions from the three-door city car are as 103g/km and fuel economy from is upwards of 60mpg from petrol models.
Wren added: ""HCM is continually looking for more cost effective and efficient ways of delivering meals. The new C1s, which will be joined by more of these cars in our fleet, provide significant operational, financial and environmental benefits."
The Citroen C1 comes in three- and five-door variants and is available to buy from Citroen dealers across the UK.