[Napoli] «The containment of electricity consumption is a very current issue today, but energy efficiency, one of its fundamental components, has now passed the century of life. Daylight-saving time was in fact established in Italy, and in several other European countries, in 1916. Every year, Terna assesses the effect of this measure on electricity consumption and estimates the economic and environmental benefits for citizens and businesses».
«We are Silvia Napoli [Caprabianca] and Mauro Caprabianca, and we work in the Market Operations and Analysis structure within Terna's Dispatching Department. Today, we will better understand what is behind assessing the savings related to the application of daylight-saving time».
[Jingle with speaker] Sala Dati, the monthly podcast by Terna that explores the world of electricity consumption in Italy
[Caprabianca] «Every year, at the end of March, Terna publishes an estimate of the effect that the application of daylight-saving time will have for the following 7 months in terms of lower electricity consumption, and therefore what the saving on energy costs will be for the country and the environmental benefit linked to the reduction of greenhouse gas emissions. For 2023, we have estimated that in the months in which daylight-saving time is in force, from 26 March to 29 October, Italy will save around 410 million kilowatt hours. To get a better idea, it is as if more than 150,000 Italian households did not consume electricity throughout the year. Silvia, why is less electricity consumed in daylight-saving time?».
[Napoli] «In the final part of the month of March, with the longer days, many people wake up when there has already been light for at least an hour, while in the evening, artificial lighting is still used for several hours. With daylight-saving time, on the one hand, one hour of natural light is gained, thus reducing the use of artificial lighting in homes, offices, streets and businesses in the evening. Mauro, can you explain how this saving is calculated?».
[Caprabianca] «From a conceptual point of view, it is quite simple: we compare the electricity consumption of the previous period with that of the period following the coming into force of daylight-saving time. However, in reality, it is a little more complicated because the change in electricity consumption is linked to various factors: these include the temperature, cloudiness or, for example, holidays and long weekends. Our task is to remove the trend in demand from these elements so that only the effect of the time shift remains. So, in practice, we analyse the electricity consumption recorded in the week before and after daylight-saving time and we apply corrective factors to make them comparable. On the other hand, it is more complicated to estimate the projection of this benefit, which tends to decrease in the weeks following the time change. Silvia, would you like to explain why, in addition to energy, daylight-saving time also brings a benefit to the environment?».
[Napoli] «Yes, of course... as you know, even if the production of renewable sources plays an increasingly important role, the energy that we consume is partly produced by traditional power stations which, using fossil fuels, emit carbon dioxide, which contributes to the greenhouse effect. The application of daylight-saving time makes it possible to use these pollutant sources less and thus reduce CO2
emissions. We have estimated that this year, thanks to daylight-saving time, about 200,000 tonnes of CO2 will not be emitted into the atmosphere. Daylight-saving time, therefore, is a benefit for the environment, but also for our pockets: lower consumption also means lower costs. Since 2004, according to our analyses, daylight-saving time has saved us a total of 10.9 billion kWh, equal to about €2 billion».
[Caprabianca] «It is a contribution of absolute importance even if certainly not decisive! However, the effectiveness of the measure is not the same for all countries, and today, there are those who question it, but also those who propose to extend the daylight-saving time period or even to keep it all year round. In absolute terms, energy savings are decreasing from year to year because with the spread of LED light bulbs and many high-efficiency systems, the energy required for lighting or other assets has decreased. It would also be advisable for the decision to be coordinated at European level to avoid creating differences between countries that use the same time zone today and apply daylight-saving time on the same days».
[Napoli] «We’ve been Silvia Napoli and Mauro Caprabianca and you’ve been listening to the fifth episode of Sala Dati, the podcast about electricity consumption in Italy explained by Terna professionals».
