WORK WITH US |  General Archive |  Suppliers |  Contacts 


Terna: in 7 months of daylight-saving time, consumption was reduced by 567 million kilowatt hours



October 2017

    Sunday 29 October, the hands of the clock are moved back one hour; at 03:00 winter time returns

    Savings of € 110 million for the electricity system


    CO2 reduced by 320 thousand tonnes

    After seven months of daylight-saving time, winter time will return on Sunday 29 October: at 03:00, the hands of the clock are moved back one hour. Daylight saving time will return from 25 March 2018.

    According to data collected by Terna, the company that manages the national electricity grid, from 26 March 2017, thanks to the extra hour of daylight which means a reduction in the need for artificial light, Italy saved an overall total of 567 million kilowatt hours (equal to the annual electricity consumption of over 200 thousand families), corresponding to a 320-tonne reduction in atmospheric CO2 emissions.

    Considering that in the period of reference, one kWh cost an average of 19.5 eurocents to the typical domestic user (before tax), the economic saving resulting from daylight-saving time for 2017 is € 110 million.

    As usual, the highest electricity savings were recorded in the months of April and October. This is due to the fact that these two months have “shorter” days in terms of natural light, compared to other months in the period. Moving the hands of the clock ahead by one hour postpones the use of artificial light while professional activities are still in progress. Instead, during the summer months such as July and August, as the days are already longer compared to April, the delay in turning on the lights occurs in the evening when most working activities have ended, leading to less significant results in terms of electricity savings.

    According to data analysed by Terna, between 2004 and 2017, the drop in electricity consumption as a result of daylight saving time has amounted, overall, to roughly 8 billion and 540 million kWh – a volume equivalent to the annual electricity needs of a region such as Sardinia – and has led, in economic terms, to a saving for citizens of around € 1.435 billion.

    On the homepage of the Terna website,, the “load curve” is displayed, representing the real-time consumption of electricity in Italy.

    Download press release